Fume Hood Performance 2

PROCEDURAL STANDARDS FOR

FUME HOOD PERFORMANCE TESTING

2009 – FIRST EDITION NATIONAL ENVIRONMENTAL BALANCING BUREAU

PROCEDURAL STANDARDS FOR FUME HOOD PERFORMANCE TESTING

2009 – FIRST EDITION

National Environmental Balancing Bureau 8575 Grovemont Circle Gaithersburg, Maryland 20877-4121 301-977-3698 301-977-9589 FAX www.nebb.org

FOREWORD The purpose of the NEBB Procedural Standards for Fume Hood Performance Testing is to establish a uniform and systematic set of criteria for the performance testing of fume hoods. This publication is the first edition of the Procedural Standard. Similar to the other NEBB disciplines, the Procedural Standard serves as the anchor for the program. Fume hoods and other safety control environments, such as bio-safety cabinets, offer a distinct set of challenges to the firms and individuals testing the field performance of these specialized, containment enclosures. The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) has developed an ANSI/ASHRAE Standard 110 Method of Testing Performance of Laboratory Fume Hoods. Another standard is ANSI/AIHA Standard Z9.5 Laboratory Ventilation. These publications define the testing procedures to be used when testing fume hoods and are well recognized and respected in this area of expertise. The NEBB discipline builds on these standards and complements them by providing a program that combines their testing requirements with a complete package for firm certification. The NEBB Procedural Standard and the NEBB Fume Hood Testing program define the requirements for firm certification, for Certified Professional educational and experience requirements, for reporting consistencies, and for instrumentation requirements. This Procedural Standard is similar to other NEBB Procedural Standards in that it is divided into two distinct Parts: Standards and Procedures. These FHT procedural standards have been developed using language defined by “Shall, Should, and May” as it relates to the standards and procedures described in this manual. It is important to note these particular words throughout this manual and how they pertain to the NEBB standards and procedures. These standards and procedures are intended as the minimum NEBB requirements that a NEBB Certified FHT Firm shall follow when performing fume hood testing and reporting the results. Contract documents may supercede the NEBB requirements. These Procedural Standards have been carefully compiled and reviewed by the NEBB Technical Committees. Part 1 STANDARDS Part 1, STANDARDS, covers the requirements for Quality Control and Compliance, Instrumentation Requirements, and FHT Reports. The report requirements allow the NEBB Certified Firm more flexibility in designing their reports by prescribing sets of information that "Shall, Should and/or May" be required to complete an FHT Report. Part 2 PROCEDURES Part 2, PROCEDURES, covers required testing procedures to be followed when using ASHRAE 110 and ANSI Z9.5. Part 2 also addresses criteria and testing procedures other than those dictated by those referenced standards. This Procedural Standard allows that flexibility. APPENDICES The Appendices includes a suggested NEBB FHT specification, test illustrations, ejector specifications references and engineering formulas. This Edition of the FHT Procedural Standards, when used by NEBB Certified FHT Firms, will assure the building owner of standard, accurate reporting of fume hood performance. Andrew P. Nolfo, P.E. NEBB Technical Director III

FOREWORD The purpose of the NEBB Procedural Standards for Fume Hood Performance Testing is to establish a uniform and systematic set of criteria for the performance testing of fume hoods. This publication is the first edition of the Procedural Standard. Similar to the other NEBB disciplines, the Procedural Standard serves as the anchor for the program. Fume hoods and other safety control environments, such as bio-safety cabinets, offer a distinct set of challenges to the firms and individuals testing the field performance of these specialized, containment enclosures. The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) has developed an ANSI/ASHRAE Standard 110 Method of Testing Performance of Laboratory Fume Hoods. Another standard is ANSI/AIHA Standard Z9.5 Laboratory Ventilation. These publications define the testing procedures to be used when testing fume hoods and are well recognized and respected in this area of expertise. The NEBB discipline builds on these standards and complements them by providing a program that combines their testing requirements with a complete package for firm certification. The NEBB Procedural Standard and the NEBB Fume Hood Testing program define the requirements for firm certification, for Certified Professional educational and experience requirements, for reporting consistencies, and for instrumentation requirements. This Procedural Standard is similar to other NEBB Procedural Standards in that it is divided into two distinct Parts: Standards and Procedures. These FHT procedural standards have been developed using language defined by “Shall, Should, and May” as it relates to the standards and procedures described in this manual. It is important to note these particular words throughout this manual and how they pertain to the NEBB standards and procedures. These standards and procedures are intended as the minimum NEBB requirements that a NEBB Certified FHT Firm shall follow when performing fume hood testing and reporting the results. Contract documents may supercede the NEBB requirements. These Procedural Standards have been carefully compiled and reviewed by the NEBB Technical Committees. Part 1 STANDARDS Part 1, STANDARDS, covers the requirements for Quality Control and Compliance, Instrumentation Requirements, and FHT Reports. The report requirements allow the NEBB Certified Firm more flexibility in designing their reports by prescribing sets of information that "Shall, Should and/or May" be required to complete an FHT Report. Part 2 PROCEDURES Part 2, PROCEDURES, covers required testing procedures to be followed when using ASHRAE 110 and ANSI Z9.5. Part 2 also addresses criteria and testing procedures other than those dictated by those referenced standards. This Procedural Standard allows that flexibility. APPENDICES The Appendices includes a suggested NEBB FHT specification, test illustrations, ejector specifications references and engineering formulas. This Edition of the FHT Procedural Standards, when used by NEBB Certified FHT Firms, will assure the building owner of standard, accurate reporting of fume hood performance. Andrew P. Nolfo, P.E. NEBB Technical Director III

FUME HOOD COMMITTEE MEMBERS AND OTHER CONTRIBUTORS FOR CURRENT EDITION

Current FHT Committee: Bohdan (Don) Fedyk, Chairman Buffalo, New York Michael J. Kelly Bethlehem, Pennsylvania Michael L. Lancette St. Paul Park, Minnesota Thomas R. McKeen, PE San Antonio, Texas David G. McFarlane Grand Forks, North Dakota David Muggah Sydney, Nova Scotia, Canada W. David Bevirt, PE Tucson, Arizona Andrew P. Nolfo, PE Phoenix, Arizona Additional Contributors to the First Edition: Michael P. Dolim Gaithersburg, Maryland

Randall Silva San Jose, California

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Michael A. Wieder Bethlehem, Pennsylvania

TABLE OF CONTENTS PAGE Foreword NEBB Fume Hood Testing Committee Table of Contents

III IV V

PART 1 – STANDARDS SECTION 1 Definitions

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SECTION 2 NEBB Program, Quality Control and Compliance

7 7 7 7 7 8 8 8 8 8 8 9 9 10 10 10 10 10 10 11

2.1

2.2

2.3 2.4

NEBB Programs 2.1.1 NEBB Disciplines 2.1.2 Certification of Firms 2.1.3 Certification of Professionals 2.1.4 Recertification Requirements Quality Assurance Program – Conformance Certification 2.2.1 Program Advantages 2.2.2 NEBB Quality Assurance Program Certificate Quality Control and Compliance 2.3.1 FHT Work Compliance FHT Professional Responsibilities 2.4.1 Execution of FHT Procedures 2.4.2 Technician Training 2.4.3 FHT Procedures Training 2.4.4 Instrument Use and Maintenance 2.4.5 Coordination / Supervision 2.4.6 Project Communication 2.4.7 Work Completion 2.4.8 Compilation and Submission of Final FHT Reports

SECTION 3 Responsibilities 3.1 3.2

Introduction Design and Construction Team Responsibilities 3.2.1 Design Professional’s Responsibilities 3.2.2 Construction Team Responsibilities 3.2.3 NEBB Certified FHT Firm Responsibilities

SECTION 4 Standards for Instrumentation and Calibration 4.1 4.2 4.3

Minimum Instrumentation Range and Accuracy Calibration Table 4-1 NEBB Minimum FHT Instrumentation Requirements

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13 13 13 13 14 14 15 15 15 15 16

NEBB FHT PROCEDURAL STANDARDS

TABLE OF CONTENTS

PAGE SECTION 5 Standards for Reports and Forms 5.1 5.2

Reports Required Forms 5.2.1 Report Title 5.2.2 Report Certification 5.2.3 Table of Contents 5.2.4 Report Summary / Remarks 5.2.5 All Report Pages 5.2.6 Instrument Calibration 5.2.7 Abbreviations 5.2.8 Airflow Velocity Test Report Data – Constant Volume Systems 5.2.9 Airflow Velocity Test Report Data – VAV Systems 5.2.10 Airflow Visualization Test Report Data – Local Challenge 5.2.11 Airflow Visualization Test Report Data – Large Volume Challenge 5.2.12 Tracer Gas Containment Test Report Data – Static Mode 5.2.13 Tracer Gas Containment Test Report Data – Sash Movement Effect 5.2.14 Tracer Gas Containment Test Report Data – Perimeter Scan 5.2.15 Other Fume Hood Performance Test Report Data

19 19 19 19 20 20 21 21 21 21 22 22 23 23 23 24 24 24

PART 2 - PROCEDURES SECTION 6 Laboratory and Cleanroom Safety 6.1 Introduction 6.2 Designing A Program Policy Health and Safety 6.2.1 Designing a Program Policy 6.2.2 Designing a Training Program 6.2.3 Essentials of the Health and Safety Program 6.3 Responsibilities 6.3.1 Individual Health and Safety Responsibilities 6.4 Elements Of The Program 6.4.1 Project Specific Items 6.4.2 Health and Safety Program Implementation

SECTION 7 Laboratory and Cleanroom Protocol 7.1 Introduction 7.2 Laboratory And Cleanroom Procedures 7.2.1 Gowning Procedures 7.2.2 Equipment Entrance Procedures 7.2.3 Laboratory / Cleanroom Conduct

Section 8 Overview of Testing Requirements 8.1 Introduction 8.2 Test Setup Procedures

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25 25 25 25 26 26 27 27 28 28 28 29 29 29 29 30 30 31 31 31


TABLE OF CONTENTS

PAGE 8.2.1 Fume Hood Types 8.2.2 Fume Hood Sash Configurations 8.2.3 Test Setups 8.3 ANSI/ASHRAE Standard 110 8.4 ANSI/AIHA Standard Z9.5 8.5 Preliminary Test Procedures

31 32 32 33 34 34

SECTION 9 Airflow Velocity Test Procedures

35 35 35 35 35 36 36 36 36 37 38 39 39

9.1 Introduction 9.2 Airflow Velocity Tests – Constant Air Volume (CAV) Fume Hood 9.2.1 Instruments and Equipment 9.2.2 Test Procedures (Average Airflow Face Velocity) 9.2.3 Acceptance 9.2.4 Reporting 9.3 Airflow Velocity Tests – Variable Air Volume (VAV) Fume Hood 9.3.1 Instruments and Equipment 9.3.2 Test Procedures (Average Airflow Face Velocity) 9.3.3 Test Procedures (Response Time) 9.3.4 Acceptance 9.3.5 Reporting

SECTION 10 Airflow Visualization Test Procedures 10.1 10.2

10.3

Introduction Airflow Visualization Tests – Local Challenge 10.2.1 Instruments and Equipment 10.2.2 Test Procedures 10.2.3 Acceptance 10.2.4 Reporting Airflow Visualization Tests – Large Volume Challenge 10.3.1 Instruments and Equipment 10.3.2 Test Procedures 10.3.3 Acceptance 10.3.4 Reporting

SECTION 11 Tracer Gas Containment Test Procedures 11.1 11.2

Introduction Tracer Gas Containment Tests 11.2.1 Instruments and Equipment 11.2.2 Test Procedures (Static Mode) 11.2.3 Acceptance (Static Mode) 11.2.4 Reporting (Static Mode) 11.2.5 Test Procedures (Sash Movement Effect) 11.2.6 Acceptance (Sash Movement Effect) 11.2.7 Reporting (Sash Movement Effect) 11.2.8 Test Procedures (Perimeter Scan) 11.2.9 Acceptance (Perimeter Scan) 11.2.10 Reporting (Perimeter Scan)

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41 41 41 41 41 42 42 42 42 43 43 43 45 45 45 46 46 47 48 48 48 49 49 49 49


TABLE OF CONTENTS

PAGE SECTION 12 Optional Tests and Procedures 12.1 12.2 12.3

Introduction Other Tests and Procedures Supplementary Tests and Procedures 12.3.1 Room Airflow Velocity Tests 12.3.2 Temperature/Humidity Uniformity Tests 12.3.3 Sound and Vibration Level Tests 12.3.4 Cross Draft Condition Tests 12.3.5 Other Tests

51 51 51 51 51 52 52 52 53

APPENDICES APPENDIX A APPENDIX B APPENDIX C APPENDIX D APPENDIX E

Sample FHT Specification Example Test Illustrations Ejector System Specifications References and Referenced Publications Engineering Formula and Examples

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PART 1 - STANDARDS SECTION 1 DEFINITIONS These procedural standards have been developed using language defined by “Shall, Should, and May" as it relates to the standards and procedures described in this publication. It is important to note these particular words throughout this publication and how they pertain to NEBB standards and procedures. Acceptance Criteria: The value or range of values which is compared to the measured value that will determine if the results of the test pass or fail. Accuracy: The capability of an instrument to indicate the true value of a measured quantity. AHJ: The local governing Authority Having Jurisdiction over the installation. Air Supply Fixtures: Devices or openings through which air flows into the laboratory room. For the purpose of this standard all accessories, connecting duct adapters, or other mounting airways shall be considered part of the supply fixture and reported as a unit or an assembly. Some specific supply fixtures are defined as follows: grille: a louvered or perforated face over an opening. register: a combination grille and damper assembly. diffuser: an outlet designed to mix supply air and room air and to distribute it in varying directions. perforated ceiling: a ceiling with perforated panels used to distribute the air uniformly throughout the ceiling or a portion of the ceiling. Filter pads may be used to achieve a similar result. Auxiliary Air: Unconditioned or partially conditioned supply or supplemental air delivered to a laboratory at the laboratory fume hood to reduce room air consumption. Calibrate: The act of comparing an instrument of unknown accuracy with a standard of known accuracy to detect, correlate, report, or eliminate by adjustment any variation in the accuracy of the tested instrument. Control Level: The average measured concentration of tracer gas, in parts of tracer gas per million parts of air by volume (ppm), that is not exceeded at the hood face with a 4.0 Lpm release rate. Deficiency: Any circumstance or operation that affects the measurement results as compared to the design criteria required by the contract documents. Design Sash Opening: The position of the sash at which the design team assumes that the fume hood will be operating. Face Velocity: The average velocity of air moving perpendicular to the hood face, usually expressed in feet per minute (fpm) or meters per second (m/s).

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SECTION 1 DEFINITIONS

Fume Hood (sometimes referred to as a laboratory hood): A box-like structure enclosing a source of potential air contamination, normally with one open or partially open side, into which air is moved for the purpose of containing and exhausting air contaminants. A fume hood is generally used for bench-scale laboratory operations but does not necessarily involve the use of a bench or table. Fume Hood System: An arrangement consisting of a fume hood, its adjacent room environment, and the air exhaust equipment, such as blowers and ductwork, required to make the hood operable. Function: For the purposes of this NEBB Standard, function refers to the specific type of data measurement specified in Section 4, Standards for Instrumentation and Calibration. High Value of Range: The maximum response time divided by the average response time of the VAV Response Time Test. Value is expressed as a percentage. Hood Face: The plane of minimum area at the front portion of a laboratory fume hood through which air enters when the sash(es) is (are) fully opened, usually in the same plane as the sash for a hood with a vertical sash. For a hood with horizontal sash(es) or a combination sash, the hood face is usually the plane passing through the midpoint between the inner and outer sashes. Lazy Airflow: Airflow within the hood is described as lazy when smoke remains on the work surface without smoothly flowing to the back baffle. LPM: Liters per minutes. Low Value of Range: The minimum response time divided by the average response time of the VAV Response Time Test. Value is expressed as a percentage. May: Used to indicate a course of action that is permissible as determined by the NEBB Certified FHT Firm. Maximum Sash Opening: The position of the sash at which the fume hood has the largest opening. N/A: Not Available, Not Applicable, or Not Accessible. The simple notation “N/A” without definition is not allowed. NEBB Certified FHT Firm: A NEBB Certified FHT Firm is a firm that has met and maintains all the requirements of the National Environmental Balancing Bureau for firm certification in Fume Hood Performance Testing and is currently certified by NEBB. A NEBB Certified FHT Firm shall employ at least one NEBB Certified FHT Professional in a full time management position. NEBB Certified FHT Report: The data presented in a NEBB Certified FHT Report accurately represents system measurements obtained in accordance with the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing. A NEBB Certified FHT Report does not necessarily guarantee that systems measured conform to the design requirements or stated guidelines. The report is an accurate representation of the measured results only. NEBB Certified FHT Professional: A NEBB Certified FHT Professional is a full time employee of the firm in a management position who has successfully passed the professional level written and practical qualification examinations and maintains the Certified FHT Professional recertification requirements of NEBB.

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Operating Sash Opening: The position of the sash at which the fume hood user places the sash while working at the face of the fume hood. The operating sash opening should take into consideration all of the procedures to be conducted in the fume hood. There may be more than one operating sash opening. Performance Rating: Rating definition of the Static Mode Test portion of the Tracer Gas Tests. It is comprised of a series of letters and numbers consisting of the letters AM, AI, or AU, and three-digit number: AM yyy AI yyy AU yyy Where: AM indicates the test setup is "As Manufactured," AI indicates the test setup is "As Installed," AU indicates the test setup is "As Used," yyy indicates the control level of tracer gas established by the test in ppm. As an example: A test rating of AU 0.500 would indicate that the fume hood controls the leakage into the laboratory to 0.500 ppm at the mannequin's sensing point with a tracer gas release rate of 4.0 Lpm. Positional Sash Movement Effect Control Level: The maximum 45-second moving average of the tracer gas concentration observed during a series of sash movement tests at one ejector and mannequin position. Positional Control Level: The average tracer gas concentration at a position during a test. Precision: The ability of an instrument to produce repeatable readings of the same quantity under the same conditions. The precision of an instrument refers to its ability to produce a tightly grouped set of values around the mean value of the measured quantity. PPM: Parts per million. Procedure: The approach to and execution of a sequence of work operations to yield a repeatable and defined result. Range: The upper and lower limits of an instrument’s ability to measure the value of a quantity for

which the instrument is calibrated. Relative Range: The range from the Low Value of Range to the High Value of Range. Reported as percentages. Release Rate: The rate of release, in actual liters (litres) per minute (Lpm), of tracer gas during a hood test. Repeatability: The difference from the Low Value of Range to the High Value of Range. Reported as a percentage. Resolution: The smallest change in a measured variable that an instrument can detect.

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Reverse Flow: Airflow within the hood when smoke released in the hood moves forward toward the front of the hood. This term does not apply to the forward motion of the roll inside the hood that occurs in the upper cavity of the hood above the hood opening or to the cyclonic motion that occurs behind a closed horizontal sash. Roll: The rotation of air, commonly referred to as vortex, in the upper cavity of the hood. The roll is induced by the momentum of the air entering the hood through the hood opening. Sash Movement Effect: The maximum of the positional sash movement effects for all the positions tested on a particular hood. Sash Movement Effect Performance Rating: Rating definition of the Sash Movement Effect Test portion of the Tracer Gas Tests. It is comprised of a series of letters and numbers consisting of the letters SME-AM, SME-AI, or SME-AU, and three-digit number: SME-AM yyy SME-A I yyy SME-AU yyy Where: SME means "sash movement effect," AM indicates the test setup was "As Manufactured," AI indicates the test setup was "As Installed," AU indicates the test setup was "As Used," yyy equals the sash movement effect, in ppm. For example: A test rating of SME-AI 10.0, indicates the fume hood was tested in the “AsInstalled” test setup and that the maximum 45-second rolling average concentration of tracer gas measured during a sash movement test was 10.0 ppm with a tracer gas release rate of 4.0 Lpm . Shall: The term is used to indicate mandatory requirements that must be followed in order for the project to become a NEBB certified project. Work must conform to these standards and procedures and no deviation is permitted. Note: In the event unique circumstances prevent a required action from being fulfilled, a notation shall be included in the FHT report explaining the reason that the requirement was not completed. For example, such notation could be one of the following: Not Available, Not Applicable, or Not Accessible. The simple notation “N/A” without definition is not allowed. Should: The term is used to indicate that a certain course of action is preferred but not necessarily required. Specified Rating: The hood performance rating as specified, proposed, or guaranteed either in the purchase of the hood or in the design and construction of the laboratory, or both. Standard: A required qualification, action, or result for FHT work. Standard Operating Procedure: An internal policy prepared by the each FHT firm and / or prepared by the Owner/Buyer. Procedures are written to provide guidance, direction, and step-by-step details

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relating to issues such as safety, testing protocols, acceptance criteria, etc. NEBB FHT Firm SOP’s shall be utilized in an absence of SOP’s prepared by the Owner. Test Sash Opening: The position or positions of the sash at which the fume hood is tested. Test Setup (Test Setup Mode): Defines the condition of the fume hood being tested. There are three distinct conditions that the fume hood may be tested: As-Manufactured (AM): With this test setup, the fume hood is tested at the manufacturer’s facility or under conditions that would replicate those conditions. The hood and work surface shall be void of all process equipment, apparatus and chemicals. As-Installed (AI): With this test setup, the actual fume hood is tested in its installed, operating condition. All supply, exhaust and return air systems are installed, operable and under control. The hood and work surface shall be void of all process equipment, apparatus and chemicals. As-Used (AU): This test setup is the same as the As-Installed setup except the hood is being utilized for actual process work. Experiment equipment, chemicals and processes are being carried out inside the hood while the fume hood performance testing is being performed. This means that all normal operating equipment within the hood shall be activated and operational including items such as all heat and vapor producing appliances, physical obstructions, etc. Testing: The use of specialized and calibrated instruments to measure fluid quantities, temperatures, pressures, rotational speeds, electrical characteristics, velocities, and sound and vibration levels, Testing, Adjusting, and Balancing (TAB): A systematic process or service applied to heating, ventilating and air-conditioning (HVAC) systems and other environmental systems to achieve and document air and hydronic flow rates. The standards and procedures for providing these services are addressed in the current edition of the NEBB “PROCEDURAL STANDARDS FOR THE TESTING, ADJUSTING AND BALANCING OF ENVIRONMENTAL SYSTEMS.” VAV Speed of Response: The time, measured from the first movement of the sash, for the VAV system to restore the slot velocity or airflow to 90 percent of the average steady-state value. VAV Time to Steady State: The time, measured from the first movement of the sash, for the VAV system to restore and maintain the average slot velocity of airflow between 90 and 110 percent of the average steady-state value. Work Surface:

The surface that the fume hood sets on.

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SECTION 2 NEBB PROGRAM, QUALITY CONTROL AND COMPLIANCE 2.1 NEBB PROGRAMS The National Environmental Balancing Bureau (NEBB) is a not-for-profit organization founded in 1971 to: a) develop standards, procedures and programs for the performance of testing, balancing and commissioning of building systems, b) promote advancement of the industry through technical training and development, c) operate programs to certify firms and qualify individuals who meet and maintain NEBB standards with integrity. Additional information on NEBB Programs is available at www.nebb.org . 2.1.1 NEBB DISCIPLINES NEBB establishes and maintains standards, procedures , and specifications for work in its various disciplines, which include: a) b) c) d) e) f) g)

Testing-Adjusting-Balancing (TAB) -- Air and Hydronic Systems Sound (S) Measurement Vibration (V) Measurement Cleanroom Performance Testing (CPT) Building Systems Commissioning (BSC) Fume Hood Performance Testing (FHT) Retro-Commissioning (RCx-EB)

Each discipline is anchored by a NEBB Procedural Standards manual that provides guidelines for work to be performed. NEBB also has created technical manuals, training materials and programs, and seminars to enhance and support each discipline. 2.1.2 CERTIFICATION OF FIRMS NEBB certifies firms that meet certain criteria, ensuring strict conformance to its high standards and procedures. Among other requirements, NEBB Certified FHT Firms must document a record of responsible performance, own a complete set of instruments and equipment required for the sophisticated techniques and procedures necessary to take and report fume hood testing measurements, and have a NEBB Certified FHT Professional as a full-time employee. 2.1.3 CERTIFICATION OF PROFESSIONALS NEBB also establishes professional qualifications fo r the supervision and performance of work in its various disciplines. NEBB Certified FHT Profe ssionals must have extensive experience, and they must pass appropriate, college-level written examinations and demonstrate certain practical working knowledge and proficiency in the use of instruments required for the various disciplines.

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SECTION 2 NEBB PROGRAM, QUALITY CONTROL AND COMPLIANCE

2.1.4 RECERTIFICATION REQUIREMENTS Through the recertification procedures, the firm must verify that its NEBB Certified FHT Professional is still on staff and that it continues to own a complete se t of instruments that are in current calibration. In addition, the firm's NEBB Certified FHT Profe ssional renews his or her certification annually. Among other requirements, the Certified Professional must keep abreast of developments in their discipline by successfully completing continuing education requirements annually.

2.2 QUALITY ASSURANCE PROGRAM - CONFORMANCE CERTIFICATION The credibility of NEBB is built by maintaining in tegrity through high standards, quality programs, and demonstrated capabilities of its certified firms. As further assurance, NEBB offers a Quality Assurance Program to guarantee that the work will be accomplished in accordance with its standards. NEBB’s Quality Assurance Program applies to each proj ect. It assures that the NEBB Certified Firm will perform specified services in conformity with the current applicable NEBB Procedural Standards. 2.2.1 PROGRAM ADVANTAGES The NEBB Quality Assurance Program affords building owners, architects, engineers and other agents a reliable basis for specifying work within the various disciplines of NEBB. The program promotes proper execution of projects by ensur ing compliance with NEBB standards and procedures. 2.2.2 NEBB QUALITY ASSURANCE PROGRAM CERTIFICATE The NEBB Quality Assurance Program Conformance Certificate is not required, but is available for any project.

2.3 QUALITY CONTROL AND COMPLIANCE Building owners are entitled to a professional service by every NEBB Certified Firm on every project, whether the job is NEBB-specified or not. It is the responsibility of the NEBB Certified FHT Firm and its NEBB Certified FHT Professional to establis h and maintain procedures and practices that will assure a consistent pattern of high quality work on all projects. This point cannot be overemphasized. 2.3.1 FHT WORK COMPLIANCE Either the design professional or the owner / buyer should adequately define the scope of the fume hood performance testing services. Many of today ’s contract documents do not define the actual scope of services to be performed on the project. Contract documents may reference desired procedures and may include statements such as "…the work will be performed in accordance to NEBB Standards…" or, the contract documents may refer to NEBB and that fume hood performance testing work “…shall be done in accordance with the reference standard…” or, merely allude to the NEBB organization, ASHRAE, or ANSI, or owne r / buyer defined reference standards and make reference to fume hood performance testing work. When contract documents do not clearly identify the exact scope of fume hood performance testing services, the NEBB Certified FHT Professional shall make every attempt to have the design professional, or the owner / buyer, dictate the actual scope of work. Regardless of what is the scope of work, in all cases the process by which the data is acquired shall conform to the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing.

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References to desired procedures may include statements such as "the work will be performed in accordance to NEBB Standards." When specifications indicate that the fume hood testing work shall be performed in accordance with NEBB standards, t he FHT procedures will conform to the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing and must be performed by a NEBB certified firm . The scope of work shall be performed as specified in the contract documents or as agreed to between the owner / buyer and the NEBB Certified FHT Firm. Ea ch relevant or applicable item as identified in the scope of work shall be performed and recorded in NEBB FHT Final Report. Data presented in the NEBB FHT Final Report shall provide an accurate record of the system tests, measurements, data and information. a. The NEBB Certified FHT Firm and the NEBB Cert ified FHT Professional are allowed to sign and stamp a fume hood testing report as a NEBB Certified FHT Report only when the procedures and requirements as identified in these Procedural Standards have been followed. b. A NEBB Certified FHT Report should consist of all three primary fume hood tests (Airflow Velocity Tests, Airflow Visualizations Tests, and Tracer Gas Containment Tests), but may consist of any single primary test or any combination of primary tests as described in these Procedural Standards. To qualify as a NEBB Certified Report, the procedures and requirements for each primary test included in the report SHALL adhere to the requirements of these Procedural Standards. c. For some projects, the scope of work of the fume hood testing may require testing requirements, procedures, reporting requirements, etc. that are different from those required by this Procedural Standard. The scope of work may require testing to another industry standard or an owner / buyer defined set of testing requirements. For these projects, the Certified FHT Final Report MAY be signed and stamped as a NEBB Certified FHT Report only if the procedural variances are clearly delineated in the project scope of work and identified on the report Certification Page. See Section 5.2.2. d. Any project that does not comply with the minimum SHALL requirements of this standard and does not clearly identify the specific procedural variances required by the fume hood testing contract on the certification page SHALL NOT be signed and stamped as a NEBB certified FHT report. All references to NEBB, including NEBB logos, stamps, certifications, etc. SHALL be removed from the report.

2.4 FHT PROFESSIONAL RESPONSIBILITIES It is the responsibility of the NEBB Certified FHT Pr ofessional to control the quality of the fume hood performance testing work. This means that the NEBB Certified FHT Firm, through its NEBB Certified FHT Professional, shall satisfy the contract obligations set forth in the drawings and applicable specifications. 2.4.1 EXECUTION OF FUME HOOD TESTING PROCEDURES The NEBB Certified FHT Professional shall have pr oject responsibility, which includes authority to represent the NEBB Certified FHT Firm. Exampl es of project responsibility may include labor decisions, negotiating change orders, committing to contract interpretations and implementing changes in job schedules.

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The NEBB Certified FHT Professional has the responsib ility to assure that the measurements of the fume hood performance testing have been performed in accordance with these Procedural Standards and the contract documents to assure the accuracy of all data included in the final report. Factors such as instrument use, coordination / supervision, work instructions, and project communication play a critical role in achieving this requirement. 2.4.2 TECHNICIAN TRAINING The NEBB Certified FHT Professional has a responsibility to assure that technicians performing the work are properly trained and possess sufficient skills . Areas that should be stressed are fume hood performance testing procedures, instrument use and maintenance, safety procedures, coordination and supervision, and project communication. 2.4.3 FHT PROCEDURES TRAINING NEBB Certified FHT Professionals must be prepared to completely measure and record data in the manner specified. It is mandatory that NEBB Ce rtified FHT Professionals possess the ability to perform the specific tasks and procedures requir ed for each project. An understanding of building system fundamentals and operating characteristic s is important, and technicians should possess rudimentary knowledge of all related systems and procedural considerations. This may require periodic training to promote knowledge and skill development as well as to facilitate the transfer of knowledge and basic skills in the use of new technology. 2.4.4 INSTRUMENT USE AND MAINTENANCE NEBB Certified FHT Professionals shall possess know ledge and skill in the proper use and care of instruments required to perform the work. This shall include a thorough understanding of the operating principles and use of fume hood equipment and instruments. Considerations for the delicate nature of many of the instruments typically us ed, as well as the adverse effects of dirt, shock, jarring movements and exceeding rated capacities, shall be addressed along with the proper methods for storing and transporting the instruments. 2.4.5 COORDINATION / SUPERVISION The NEBB Certified FHT Professional shall be respons ible for directing technicians in performing the work. Instructions may delineate items such as the scope of work, location, type and quantity of measurements, etc. so that field personnel may know ex actly what to do and what is required of them. 2.4.6 PROJECT COMMUNICATION The NEBB Certified FHT Professional shall report on progress made toward work completion, when required, as well as report and address problems if encountered. When a problem exists, the NEBB Certified FHT Professional should notify the appropriate project personnel. 2.4.7 WORK COMPLETION The NEBB Certified FHT Professional shall determine when the fume hood performance testing work has been completed, and when to submit the report. Generally, the specified fume hood performance testing field work is complete when: a) All specified fume hood performance testing is completed; or b) Reasonable efforts within the extent of testing for fume hoods have been performed in an effort

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to complete all required measurements. The NEBB Certified FHT Professional shall notify the appropriate project personnel of any significa nt system deficiencies preventing fume hood performance testing from being performed before the final report is submitted. 2.4.8 COMPILATION AND SUBMISSION OF FINAL FHT REPORTS Reports shall include information and data to provide an accurate quantitative and qualitative record of system measurements and information. R eports also shall include notes and comments, as appropriate, to provide the reviewer with additional details related to the test procedure, system operation and results. Reports shall meet the criteria listed in Section 5. The certification page shall bear the stamp of the NEBB Certified FHT Professional. The stamp on the certification page shall be signed as evidence that the NEBB Certified FHT Professional has personally reviewed and accepted the report. Signature stamps are specifically prohibited.

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12

SECTION 3 RESPONSIBILITIES 3.1 INTRODUCTION Many approaches can be taken to deliver successful performance testing of fume hoods on a project. In order to maximize value and benefits from fume hood performance testing, it is important to understand that the design professionals and other construction team members have responsibilities that will affect the outcome of the fume hood testing process. The following outline represents recommended practices that may take place on a conventional design/bid/buy/construct delivery project or on a direct procurement project between the Owner/Buyer and the NEBB Certified FHT Firm. While other delivery approaches exist, the overall concept of the delineation of responsibilities remains. The Owner/Buyer must be the responsible party that dictates the recommended following procedures.

3.2 DESIGN AND CONSTRUCTION TEAM RESPONSIBILITIES 3.2.1 DESIGN PROFESSIONAL’S RESPONSIBILITIES It is recommended that the contract documents must: a) Specify the equipment, systems and scope of testing services to be performed for the fume hoods on the project. NEBB standards and procedures define industry best practices to perform the measurements. b) Define who retains the services of the NEBB Certified FHT Firm and require that the NEBB Certified FHT Firm be retained early in the construction process. c) Clearly define on the contract documents all fume hood performance testing requirements including setup mode, design sash opening, acceptance criteria and reporting requirements. d) Clearly identify on the contract documents all locations where fume hood performance testing is to be performed. e) Specify that the building, mechanical, electrical and all associated work is to be completed prior to performing fume hood performance testing. f)

Specify that all building, mechanical, electrical, and other systems are completely operational, under control and performing according to the design intent prior to performing fume hood performance testing. This would include that all building automation / controls are installed, operational, calibrated and functioning properly and that the TAB work is completed. Fume hood performance testing performed prior to completion of these activities should be avoided. Actual final measurements may differ from measurements taken prior to the completion of the work.

g) Provide adequate access to all equipment and components required by the fume hood performance testing process.

13


SECTION 3 RESPONSIBILITIES

3.2.2 CONSTRUCTION TEAM RESPONSIBILITIES It is recommended that the construction team must: a) Provide the NEBB Certified FHT Firm with a conformed set of contract documents (drawings, specifications, and approved submittals), including all current approved change orders and contract modifications. b) Develop a project schedule, with the input of the NEBB Certified FHT Firm that coordinates the work of other disciplines and provides adequate time in the construction process to allow successful completion of the fume hood performance testing work. c) Notify the NEBB Certified FHT Firm of all schedule changes. d) Ensure that the building enclosure is complete, including but not limited to, all structural components, windows and doors installed, door hardware complete, floor and ceilings complete. Ensure that the building enclosure and components are complete and operational such that the performance of the fume hoods would not be adversely affected. e) Ensure that all necessary building systems are complete and are operating in a safe manner. f)

Complete the installation of permanent electrical power systems serving the building systems. Such electrical systems shall be properly installed in accordance with all applicable codes to ensure the safety of all construction personnel.

g) Perform start up of all building systems in accordance with manufacturers' recommendations. h) Complete the installation, programming (including design parameters and graphics), calibration and startup of all building control systems. Verify that the building control system provider has commissioned and documented all building control work. i)

Complete all TAB related work. A copy of the completed TAB Report shall be furnished to the NEBB FHT Firm. If this is a recertification project, provide the NEBB FHT Firm with a copy of the most recent TAB Report or the most recent Fume Hood Performance Test Report.

3.2.3 NEBB CERTIFIED FHT FIRM RESPONSIBILITIES The NEBB Certified FHT Firm SHALL: a) Follow the current NEBB standards and procedures when performing the fume hood performance testing. b) Communicate on a regular basis, through proper channels, items pertaining to design, installation or function that prevent the NEBB Certified FHT Firm from achieving completion of the FHT work in accordance with the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing. c) Perform the required fume hood performance tests. d) Publish a NEBB Certified FHT Report of final conditions that accurately reflect the results of the fume hood performance testing.

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SECTION 4 STANDARDS FOR EQUIPMENT, INSTRUMENTATION AND CALIBRATION 4.1 MINIMUM INSTRUMENTATION A NEBB Certified FHT Firm will use a variety of instrumentation to perform the specified fume hood performance tests on a project. It is the responsibility of the NEBB Certified FHT Firm to provide appropriate instrumentation that meets the minimum requirements for use on a project. Instrumentation used on a NEBB project shall be in proper operating condition and shall be applied in accordance with the manufacturer’s recommendations. Table 4-1 lists the minimum instrumentation specifications that a NEBB Certified FHT firm shall utilize in all fume hood performance testing. The NEBB Certified FHT Firm shall own all of the required instrumentation and equipment as identified in Table 4-1.

4.2 RANGE AND ACCURACY The accuracy and range as reported by the instrument manufacturer shall be verified by a testing laboratory traceable to the National Institute of Standards and Technology or equivalent institute in countries other than the United States. Calibration requirements for each function are specified and shall be met. Some instruments and accessories may not require calibration. However, if a "mechanical / electrical" device is substituted or employed in place of these types of instruments, the indicated calibration requirements noted shall apply. Instrumentation with multiple capabilities shall be accepted for more than one function when submitting documentation for a firm’s certification, providing that each separate function meets NEBB requirements.

4.3 Calibration Annual Calibration – ALL fume hood performance testing instrumentation SHALL be maintained with a current annual calibration certificate, traceable to the National Institute of Standards and Technology (NIST), or equivalent organizations in other countries, or manufacturers’ specifications, whichever is more stringent. Firms with multiple sets of instrumentation SHALL calibrate all instrumentation used by the firm on FHT projects in accordance with Table 4-1 as a minimum requirement for NEBB certification.

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SECTION 4 STANDARDS FOR EQUIPMENT, INSTRUMENTATION AND CALIBRATION

TABLE 4-1 NEBB MINIMUM FHT INSTRUMENTATION REQUIREMENTS Test Airflow Velocity Tests – Average Face Velocity (CAV & VAV) (Sections 9.2 & 9.3)

Instruments & Equipment Linear Measuring Device

Description

Equipment Stand

Stationary stand (ring stand) that will allow the airflow face velocity measuring device to be secured.

Not Required

Airflow Velocity Instrument (One of the following Shall be provided)

A digital manometer and either an array-type grid or airfoil-type probe. The manometer shall have the following characteristics:

12 Months (Meter only)

Minimum 12’ (3.6 m) tape measure capable of reading 1/16” (1.0 mm) increments

Calibration Interval Not Required

Range: 25 to 2500 fpm (0.127 to 12.7 m/s) Accuracy: ± 5% of reading (5 fpm @100 fpm) ( 0.0254 m/s @ 0.508 m/s) Resolution: 1 fpm (0.00508 m/s) Data Interval: Instrument shall be capable of data logging and data output at a minimum of one (1) second intervals. A digital thermal anemometer with the following characteristics:

12 Months

Range: 0 to 6000 fpm (0 to 30.5 m/s) Accuracy: ±3 % or ± 3 fpm (0.0152 m/s) (whichever is greater) Resolution: 1 fpm (0.00508 m/s) Data Interval: Instrument shall be capable of data logging and data output at a minimum of one (1) second intervals. Airflow Velocity Tests – Response Time (VAV) (Section 9.3

Equipment Stand

Stationary stand (ring stand) that will allow the airflow face velocity measuring device to be secured.

Not Required

Velocity Measuring Instrument (One of the following Shall be provided)

A digital thermal anemometer with the following characteristics:

12 Months

Range: 0 to 6000 fpm (0 to 30.5 m/s) Accuracy: ±3 % or ± 3 fpm (0.0152 m/s) (whichever is greater) Resolution: 1 fpm (0.00508 m/s) Data Interval: Instrument shall be capable of data logging and data output at a minimum of one (1) second intervals. Digital manometer with either a Pitot tube or an airfoil-type probe. The digital manometer shall be capable of storing / downloading data to a computer or printer and shall have the following characteristics: Range: -15.0 to +15.0 inches w.c. (-3.7 to + 3.7 kPa) Accuracy: ±1 % of reading and ± 0.005 inches w.c. (1.25 Pa) Resolution: 0.001 inch w.c. (0.25 Pa) Data Interval: Instrument shall be capable of data logging and data output at a minimum of one (1) second intervals.

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12 Months (Meter Only)


Test Air Flow Visualization Tests – Local Challenge (Section 10.2)

Air Flow Visualization Tests – Large Volume Challenge (Section 10.3)

Instruments & Equipment Small Smoke Source (One of the following Shall be provided)

Video Recorder (Optional) Large Smoke Source Generator (one of the following Shall be provided)


Description Puffer – Disposal flexible dispenser containing powder-based material Smoke Pen – Smoke emitting wick

Not Required

Smoke Stick/Bottle - A smoke stick/bottle containing titanium tetrachloride.

Not Required

Other Smoke Source - Any device that can generate a small relatively neutrally buoyant smoke source.

Not Required

An aerosol generator that can aerosolize artificial liquid medium utilizing compressed air and Laskin nozzle. Smoke Generator, such as a theatrical smoke generator with a fluid approved by the owner, designer or AHJ.

Video Recorder (Optional) Tracer Gas Containment Tests (Section 11.2)


Not Required Not Required

Not Required

Not Required

Detection Calibrator

A device used to calibrate the detection instrument in accordance with manufacturer’s specifications.

When Required

Ejector System w/critical orifice

Ejector system with critical orifice Shall conform to the requirements as indicated in the current edition of ASHRAE Standard 110. See Appendix C for instrument specifications.

Not Required

Orifice Calibrator (One of the following Shall be provided)

Mechanical device Range: 0 – 15 L/m Accuracy: ± 0.1 L/m Resolution: ± 0.1 L/m

12 months

Flow Meter (measurements shall be adjusted for specific tracer gas) Range: 1 – 10 L/m Accuracy: ± 3% Resolution: ± 0.5 L/m

Not Required

Sulfur Hexaflouride (SF6) Commercial grade (Minimum purity of 99%)

Not Required

Other acceptable gas may be used and should be approximately the same molecular weight, stability, and grade as SF6. Other acceptable gas shall be approved by the owner, designer, or AHJ.

Not Required

Tracer Gas (One of the following Shall be provided)

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Test Tracer Gas Containment Tests (Cont’d) (Section 11.2)

Instruments & Equipment Mannequin


Description A three-dimensional mannequin (torso) shall be fully clothed that would replicate a normal operator complete with laboratory coat. The height must be adjustable to meet the height requirements of the various hood configurations; i.e. standard bench hood, ADA height, walk, etc. Probe shall be placed in the normal breathing zone based on the various heights.

Video Recorder (Optional) Tracer Gas Detection Instrument (One of the following Shall be provided)


Not Required Spectrophotometer - A digital, single beam, infrared spectrophotometer consisting of a portable gas analyzer and a separate ac/dc converter. The spectrophotometer must be capable of measuring sulfur hexaflouride (SF6), or other approved tracer gas and display in concentration measurement units (ppm). The minimum response time shall be 1 second and capable of interfacing with a data logger / computer to collect readings.

12 Months

Accuracy: ±15% of reading between five times minimum detectable concentration and the upper value range. Noise: Maximum of 0.004 absorbance units (AU) with 20.25 m pathlengths at 12.0 μm wavelength and with AgBr lenses at 75°F (23° C) operating temperature. Drift: Maximum of 0.004 AU per 8 hours The internal diameter of the probe tip shall be less than 0.5 inches (12mm). The detection instrument’s calibration shall be capable of being field-verified. Electron Capture Detector (Leak Meter) – The unit shall be configured to measure sulfur hexaflouride (SF6), or other approved tracer gas and display in concentration measurement units (ppm). The minimum detection range shall be 0.01 ppm The minimum resolution shall be 0.01 ppm The minimum response time shall be 1 second and capable of interfacing with a data logger / computer to collect readings. The minimum accuracy shall be ±25% for readings between 0.05 ppm to 0.1 ppm and ± 10% for readings above 0.1 ppm The internal diameter of the probe tip shall be less than 0.5 inches (12mm). The detection instrument’s calibration shall be capable of being field-verified.

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12 Months

SECTION 5 STANDARDS FOR REPORTS AND FORMS 5.1 REPORTS The NEBB Procedural Standards for Fume Hood Performance Testing establishes minimum requirements of a NEBB Certified FHT Report. The standards have been developed and written using “Shall, Should, and May” language. It is important to note these particular words throughout this document and how they pertain to NEBB Procedural Standards. NEBB does not require the use of NEBB produced forms. Customized forms are acceptable based on the data acquisition requirements of this section. Where contract document data reporting requirements exceed the minimum requirements of NEBB, the NEBB Certified FHT Firm is responsible to meet the requirements of the contract documents. NEBB has created sample FHT reporting forms that are available to be downloaded from the NEBB website at www.nebb.org. NEBB Fume Hood Performance Testing Reports shall include the following information: A. REPORT TITLE B. REPORT CERTIFICATION C. TABLE OF CONTENTS D. REPORT SUMMARY / REMARKS E. APPROPRIATE FORMS F. INSTRUMENT CALIBRATION G. ABBREVIATIONS

5.2 REQUIRED DATA Listed below are the requirements for each NEBB Certified FHT Report in Shall, Should, and May language. 5.2.1 REPORT TITLE Shall Data: The heading: “Certified Fume Hood Performance Testing Report”; Project Name, Address, NEBB Certified FHT Firm Name, Address, Contact Information and Certification Number. May Data: Architect Name, Address and Contact Information; Engineer Name, Address, and Contact Information; HVAC Contractor Name, Address and Contact Information.

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SECTION 5 STANDARDS FOR REPORTS AND FORMS

5.2.2 REPORT CERTIFICATION The certification page SHALL bear the stamp of the NEBB Certified FHT Professional. The stamp on the certification page SHALL be signed as evidence that the NEBB Certified Professional has reviewed and accepted the report. Signature stamps are specifically prohibited. Shall Data: Project Name; Certifying NEBB Certified FHT Professional’s Name; Firm Name; Certification Number; Expiration Date; Certifying NEBB Certified FHT Professional’s NEBB Stamp (signed & dated); and either of the following exact certification verbiage. Where fume hood performance testing was performed in complete accordance with the requirements of this Procedural Standard, the following exact verbiage shall be used on the Report Certification page: "THE DATA PRESENTED IN THIS REPORT IS A RECORD OF THE FUME HOOD PERFORMANCE TESTING OBTAINED IN ACCORDANCE WITH THE REQUIREMENTS OF THE CURRENT EDITION OF THE NEBB PROCEDURAL STANDARDS FOR FUME HOOD PERFORMANCE TESTING. ANY VARIANCES FROM DESIGN / OR INDUSTRY STANDARDS WHICH EXCEED THE LIMITS SET BY THE CONTRACT DOCUMENTS, OR WHICH EXCEED THE LIMITS AGREED TO BETWEEN THE OWNER AND THE NEBB CERTIFIED FHT FIRM ARE NOTED THROUGHOUT THIS REPORT AND / OR IN THE REPORT PROJECT SUMMARY." NEBB recommends that fume hood testing should be performed in accordance with the requirements of these Procedural Standards and that all three of the primary tests (Airflow Velocity Tests, Airflow Visualizations Tests, and Tracer Gas Containment Tests) are performed. There may be cases where the scope of the work requires testing to other industry standards, or requires testing to a scope of work that is specified or as agreed to between the owner / buyer and the NEBB Certified FHT Firm. Under these conditions, a NEBB Certified FHT Firm may still issues a NEBB Certified FHT Report, but the procedural variances SHALL be clearly delineated in the project scope of work and the above Certification Statement SHALL be modified to reflect the actual scope of work or other industry testing standards to qualify as a NEBB Certified Report. See Section 2.3.1. Should Data: Disclaimer statement with the following suggested wording: “The results shown and information given in this report are certified to be accurate and complete to the extent possible by equipment and procedures used on this date. ___(Insert Company Name)_____________________________________ warrants that the equipment or system listed above and/or identified in this report is operating at the specified levels as shown, at and only at this time, and makes no other warranties, stated or implied, concerning the continued performance, operation or safety in use of this equipment past this time.” Note: The Certification Statement and the Disclaimer Statement may be included on the report title page or on a separate certification page. 5.2.3 TABLE OF CONTENTS The table of contents shall serve as a guide to the organization of the FHT report. Shall Data: Page numbers of system and component information in the report.

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5.2.4 REPORT SUMMARY / REMARKS A NEBB Certified FHT Report includes a narrative description of test methods and system set-up conditions established prior to testing. The narrative should explain the rational for system parameters, such as the Test Setup Mode, and the steps taken to achieve the desired set-up. This section also includes a listing of deficiencies in the summary and identifies the appropriate pages in the report. Deficiencies or other issues that are critical in nature relative to occupant health or facility safety shall be “red tagged” and brought to the immediate attention of the AHJ. The NEBB Certified FHT Firm SHALL NOT wait to identify these issues on a final FHT Report. Shall Data: Summary of all items that exceed Contract Document tolerances or any other items that require discussion / explanation. 5.2.5 ALL REPORT PAGES All tested items included in the NEBB FHT Report shall be clearly identified with its associated fume hood designation number or other unique descriptor. The location of each tested item shall also be identified on each report page. The location identifier should be the room number, the space number or other unique descriptor to clearly identify the tested item. The method of identification shall use schematic diagrams, mechanical plans where permissible, or a narrative description. Each data form supplied in a NEBB FHT Report shall include the name of the responsible technician / NEBB Certified FHT Professional who reported the information, and the time period the data was collected. Shall Data: Project name. All pages shall be numbered consecutively. May Data: Remarks section to record any information pertinent to the data reported on the data sheet. 5.2.6 INSTRUMENT CALIBRATION This is an overall listing of the instruments that will be used to verify the reported data. Shall Data: Instrument type Instrument manufacturer Instrument model number Instrument serial number Date of instrument calibration Tracer Gas purity certification 5.2.7 ABBREVIATIONS This is a list of definitions of the relevant abbreviations used in the report. Shall Data: A listing of all abbreviations and their definition as used in the report.

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5.2.8 AIRFLOW VELOCITY TEST REPORT DATA – CONSTANT AIR VOLUME SYSTEMS Airflow velocity tests shall be presented in graphical or tabular format for each measurement plane and location and the data shall be reported on the test reporting form(s). Shall Data: Technician Name Date of Test Test Setup Mode Sash Configuration Design Opening Sash Position (Height and Width) Design Airflow Face Velocity (fpm) (m/s)

Average Airflow Face Velocity at each grid location (fpm) (m/s) Average Airflow Face Velocity (fpm) (m/s) Highest Airflow Face Velocity (fpm) (m/s) Lowest Airflow Face Velocity (fpm) (m/s) Test Instrumentation Acceptance Criteria

Should Data: Sash Openings other than Design Conditions and associated results Temperature (°F) (°C) Altitude and Correction Factor Room Layout Drawing

5.2.9 AIRFLOW VELOCITY TEST REPORT DATA – VAV SYSTEMS Airflow velocity tests shall be presented in graphical or tabular format for each measurement plane and location and the data shall be reported on the test reporting form(s). Shall Data: Technician Name Date of Test Test Setup Mode Sash Configuration Design Opening Sash Position (Height and Width) Design Airflow Face Velocity (fpm) (m/s) Average Airflow Face Velocity at each grid location (fpm) (m/s) Average Face Velocity (fpm) (m/s) Highest Airflow Face Velocity (fpm) (m/s) Lowest Airflow Face Velocity (fpm) (m/s) Test Instrumentation

Test results reported at 25%, 50% and 100% of specified conditions Speed of Response (in seconds) (3 cycles) Low Value of Range (in percentage) High Value of Range (in percentage) Relative Range (in percentage) Repeatability (in percentage) Time to Steady State (in seconds) (3 cycles) Test Method (exhaust airflow velocity method or fume hood plenum airflow velocity method) Acceptance Criteria

Should Data: Sash Openings other than Design Conditions and associated results Temperature (°F) (°C) Altitude and Correction Factor Room Layout Drawing

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5.2.10 AIRFLOW VISUALIZATION TEST REPORT DATA – LOCAL CHALLENGE Shall Data: Technician Name Date of Test Test Setup Mode Sash Configuration Sash Opening Height and Width

Challenge Medium Used Narrative description of actual visual test results including Statement of Pass/Fail Test Instrumentation Acceptance Criteria

Should Data: Room Layout Drawing May Data: Video tape of actual test 5.2.11 AIRFLOW VISUALIZATION TEST REPORT DATA – LARGE VOLUME CHALLENGE Shall Data: Technician Name Date of Test Test Setup Mode Sash Configuration Sash Opening Height and Width

Challenge Medium Used Narrative description of actual visual test results including Statement of Pass/Fail Test Instrumentation Acceptance Criteria

Should Data: Room Layout Drawing May Data: Video tape of actual test 5.2.12 TRACER GAS CONTAINMENT TEST REPORT DATA – STATIC MODE Shall Data: Technician Name Date of test Time of test Test Setup Mode Sash Configuration Sash Opening Height and Width Room Layout Drawing Graphical display of each test

Tracer Gas Release Rate Test Instrumentation Report all individual readings, the average and peak at each sample location Report the Performance Rating and compare to the Acceptance Rating. Tests results that exceed acceptance ratings shall be noted in the report.

May Data: Video tape of actual test

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5.2.13 TRACER GAS CONTAINMENT TEST REPORT DATA – SASH MOVEMENT EFFECT Shall Data: Technician Name Date of test Time of test Test Setup Mode Sash Configuration Sash Opening Height and Width Room Layout Drawing Graphical display of each test Tracer Gas Release Rate Test Instrumentation

Report all individual readings Report the maximum 45 second rolling average associated with each opening of the sash Report the Sash Movement Performance Effect Rating If Acceptance Rating has been defined, test results that exceed acceptance rating shall be noted in the report

May Data: Video tape of actual test 5.2.14 TRACER GAS CONTAINMENT TEST REPORT DATA – PERIMETER SCAN Shall Data: Technician Name Date of test Time of test Test Setup Mode Sash Configuration Sash Opening Height and Width Room Layout Drawing Fume Hood Face Schematic

Report any measurable leakage Report the location and magnitude of the leakage Tracer Gas Release Rate Test Instrumentation If Acceptance Ratings have been defined, tests results that exceed acceptance ratings shall be noted in the report

May Data: Video tape of actual test 5.2.15 OTHER FUME HOOD PERFORMANCE TEST REPORT DATA Shall Data: As agreed to between the Owner and the NEBB Certified FHT Firm

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PART 2 - PROCEDURES SECTION 6 LABORATORY AND CLEANROOM SAFETY 6.1 INTRODUCTION A health and safety program is a definite plan of action designed to prevent accidents and occupational diseases. A health and safety program should include the elements required by all current health and safety legislation as a minimum. This document summarizes the general elements of a health and safety program. This should help NEBB firms to develop programs to deal with their specific needs. Because many small and medium-sized enterprises lack the resources of larger organizations, it is even more vital that small and medium-sized enterprises involve all employees in health and safety activities. The more comprehensive the program is, the more employee involvement can be expected. The health and safety program discussed in this section is a guideline. The project specific safety program shall be as specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. Most often the NEBB Certified FHT firm will be required to follow the client’s project specific safety program; however in the absence of this project specific safety program, the firm’s Standard Operating Procedures (SOP) for a health and safety program SHALL be followed. For this reason, the NEBB Certified FHT Firm SHALL be responsible for creating their own SOP for Safety and develop it into a Standard Operating Procedure (SOP) for their firm. At a minimum, the NEBB Certified FHT Firm’s SOP for Laboratory and Cleanroom Safety SHOULD cover design and implementation, responsibilities and elements of the plan as addressed below.

6.2 DESIGNING A HEALTH AND SAFETY PROGRAM 6.2.1 DESIGNING A PROGRAM POLICY A NEBB Certified FHT Firm’s health and safety policy is a statement of principles and general rules that serve as guideslines for action. 6.2.1.1 The policy SHOULD mention: a. b. c. d. e. f. g.

Management's commitment to protect the safety and health of employees The objectives of the program The organization's basic health and safety philosophy Who is accountable for health and safety programs The general responsibilities of all employees That health and safety shall not be sacrificed for expediency That unacceptable performance of health and safety conduct will not be tolerated

25


SECTION 6 LABORATORY AND CLEANROOM SAFETY

6.2.1.2 The policy SHOULD be: a. b. c. d. e.

Stated in clear, unambiguous, and unequivocal terms Signed by the incumbent chief executive officer Kept up-to-date Communicated to each employee Adhered to in all work activities

6.2.2 DESIGNING A TRAINING PROGRAM The objective of training is to make the implementation of health and safety policies into specific job practices and accepted practice. It also raises awareness and skill levels of a technician to an acceptable standard. 6.2.2.1 Occasions when employee training SHOULD be required are: a. b. c. d. e.

Commencement of employment Reassignment or transfer to a new job Introduction of new equipment, processes, or procedures Inadequate performance Customer and job site related chemical or biological hazards, equipment, processes, or procedures.

6.2.2.2 The NEBB Certified FHT Firm SHOULD have the following topics included in the safety training: a. b. c. d. e. f. g. h. i. j. k. l.

Safety and the supervisor Know your accident problems Human relations Maintaining interest in safety Instructing for safety Industrial hygiene Personal protective equipment Industrial housekeeping Material handling and storage Guarding machines and mechanisms Hand and portable power tools Fire protection

6.2.3 ESSENTIALS OF THE HEALTH AND SAFETY PROGRAM While different NEBB Certified FHT Firms will have different needs and requirements in their health and safety program, the following basic items MAY be considered in each case: a. b. c. d. e. f. g. h.

Individual responsibility Occupational health and / or safety representative Health and safety rules Correct work procedures Employee orientation Training Workplace inspections Reporting and investigating accidents

26

NEBB FHT PROCEDURAL STANDARDS i. j. k. l.


Emergency procedures Medical and first aid Health and safety incentives Workplace specific items

6.3 RESPONSIBILITIES 6.3.1 INDIVIDUAL HEALTH & SAFETY RESPONSIBILITIES Health and safety is the joint responsibility of both management and technicians. All health and safety activities are based on specific individual responsibilities. Responsibility may be defined as an individual's obligation to carry out assigned duties. Authority implies the right to make decisions and the power to direct others. The NEBB Certified FHT Firm MAY elect to have its Safety Officer manage the responsibilities in lieu of the NEBB Certified FHT Professional. 6.3.1.1 NEBB Certified Professionals / Safety Officer Responsibilities To fulfill their responsibilities, the NEBB Certified FHT Professional / Safety Officer SHOULD: a. b. c. d. e. f. g. h. i. j. k. l. m. n. o. p. q. r. s. t. u. v.

Instruct workers to follow safe work practices Enforce health and safety regulations Correct unsafe acts and unsafe conditions Ensure that only authorized, adequately trained workers operate equipment Report and investigating all accidents/incidents Inspect own area and taking remedial action to minimize or eliminate hazards Ensure equipment is properly maintained Update and maintain company material safety data sheets (MSDS) Promote safety awareness in workers Provide a safe and healthful workplace Establish and maintaining a health and safety program Ensure workers are trained or certified, as required Report accidents and cases of occupational disease to the appropriate authority Ensure access to medical and first aid facilities are available Ensure personal protective equipment is available Provide workers with health and safety information Evaluate health and safety performance of technicians Advise all employees on health and safety matters Coordinate interdepartmental health and safety activities Provide health and safety training Conduct research on special problems Attend health and safety committee meetings as a resource person

6.3.1.2 Field Technician Responsibilities To fulfill their responsibilities, the field technicians SHOULD: a. Use personal protection and safety equipment as required by the client project specific safety program or the NEBB firm’s SOP b. Follow safe work procedures c. Possess company material safety data sheets (MSDS) d. Know and comply with all regulations e. Report any injury or illness immediately f. Report unsafe acts and unsafe conditions g. Participate in joint health and safety committees h. Know what their responsibilities are (communication required)

27

NEBB FHT PROCEDURAL STANDARDS i. j.


Have sufficient authority to carry them out (organizational issue) Have the required ability and competence (training or certification required)

6.4 ELEMENTS OF THE PROGRAM The NEBB Certified FHT Professional / Safety Officer SHOULD address the following elements of the firm’s health and safety program: a. b. c. d. e. f. g. h. i. j. k.

Establish work procedures Analyze project hazards Establish guideline rules Conduct employee safety orientation Establish emergency procedures Establish medical and first aid action plan Perform routine project site safety audits Complete project accident / injury reports Investigate project accidents/ injuries Establish and enforce return-to-work policy Promote employee involvement in health and safety programs

6.4.1 PROJECT SPECIFIC ITEMS Examples of project specific items that SHOULD be included in health and safety programs are: a. b. c. d. e. f. g. h.

Material Safety Data Sheets (MSDS) Lock out procedures Chemical handling rules Biological material handling rules Personal hygiene Vehicle safety rules Working alone guidelines Personal protective equipment requirements

6.4.2 HEALTH AND SAFETY PROGRAM IMPLEMENTATION A good health and safety program provides a clear set of guidelines for activities that, if followed, will reduce accidents and cases of occupational disease. A NEBB Certified FHT Professional SHOULD demonstrate commitment and support the program by: a. Providing resources such as time, money, and personnel b. Ensuring that employees receive training or certification as required c. Making all applicable health and safety information available to all employees entitled to receive it d. Including health and safety performance as part of employee performances appraisals at all levels e. Attending health and safety meetings f. The program must be communicated to all employees g. Special emphasis should be given to new workers, newly appointed NEBB Certified Professionals h. Revisions to policies and procedures should be publicized i. The program should be available in a single written document (However, if separate manuals have been developed for various elements, such as accident investigation procedures, their use should be referred to in the main document)

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SECTION 7 LABORATORY AND CLEANROOM PROTOCOL 7.1 INTRODUCTION The purpose of this Section is to provide an overview of the protocol procedures that should be observed in performing the various tests in cleanrooms and laboratories. In general, there are protocols and procedures for entry, garment control, tool and equipment entry and gowning procedures. In addition to entry protocols, there are also protocols and behavior requirements while in the laboratory/ cleanroom spaces. The protocols suggested in this section are guidelines and the final procedures shall be as specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT firm. Most often the NEBB Certified FHT firm will be required to follow the client project specific protocol; however, in the absence of this project specific protocol, the firm’s SOP for laboratory and cleanroom protocol shall be followed. For this reason, the NEBB Certified FHT Firm shall be responsible for creating their own SOP for protocol and develop it into a Standard Operating Procedure (SOP) for their firm. At a minimum, the NEBB Certified FHT Firm’s SOP for Laboratory and Cleanroom Protocol should cover: gowning procedures, equipment entrance procedures, and guidelines for employee conduct.

7.2 LABORATORY AND CLEANROOM PROCEDURES 7.2.1 GOWNING PROCEDURES The processes and operations that occur in laboratory/cleanroom are unique to that particular owner and facility. Therefore the gowning procedures may vary to some degree between each cleanroom and each owner. It is imperative that the facility’s/owner’s SOP be reviewed for the specific gowning procedure. When it exists, this SOP always takes precedence and shall be followed. In many cleanroom gowning facilities there are two distinct zones in the gowning area. In some facilities, the two distinct zones may exist in the same room/space defined by some imaginary boundary. The initial area will have gloves, hair bonnets and shoe covers. Since the outside surface of the “cleanroom garments” should be kept as clean as possible, care should be used to avoid touching the outside of the garment with bare hands, hair and street shoes. This is accomplished by donning gloves, bouffant head covers and shoe covers before entering the second phase of the gowning area. It is important to note that laboratories/cleanrooms in the electronics industry may be quite different from laboratories/cleanrooms in the pharmaceutical and bio-technology industries. While gowning remains important, a high emphasis is placed on sterility. Cleaning/washing procedures can be much more rigorous. In some instances, usually associated with bio-containment spaces (i.e. BSL3 and BSL4 labs), street clothes will not be allowed into the room and a complete change of clothing is required. Upon entering the second area it is important to note that different gowning garments will be used in different facilities. Since gowning materials differ, there is no hard and fast method that can be outlined for actual gowning, but typically gowning should be done from the head down. Therefore the hood will be donned first, and then the garment, then the foot covers. Once the garment is obtained, care should

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SECTION 7 LABORATORY AND CLEANROOM PROTOCOL

be taken to avoid contaminating the exterior surface with the interior of the garment. Proper garment sizing is also required. Once obtained, the garment user should never allow the garment to touch or drag on the floor. 7.2.2 EQUIPMENT ENTRANCE PROCEDURES Tools, instrumentation and equipment also require special preparation before they can be brought into a laboratory/cleanroom. As with gowning, each facility will have their own methods and requirements for introducing these items into a cleanroom. It is imperative that the facility/owners SOP be reviewed for material ingress to their cleanroom. When it exists, this SOP always takes precedence and must be followed. Typically there will be a wipe down station for anything entering the cleanroom. There will also be a wipe down procedure. Often the procedure will involve wipe down with non-contaminating wipes moistened with de-ionized water and isopropyl alcohol (IPA) or other sterile solvents. The ingress for equipment may be a separate entrance from the gowning entrance. 7.2.3 LABORATORY/CLEANROOM CONDUCT Examples of personnel rules used by laboratory/cleanroom operators may be: a. Clean hands and face before entering clean areas b. Use lotions and soap containing lanolin to reduce skin flaking c. Avoid skin contacts with solvents d. Wearing cosmetics and skin medications may not be permitted e. Jewelry may not be permitted f. Smoking, eating and drinking is not permitted g. Required gowning, masks, gloves and shoe covers to be worn at all times h. Use proper eye protection i. Equipment, instruments and materials should be cleaned before entry j. Non-shedding paper and pens should be used. Pencils and erasers are not permitted k. Work parts are to be handled only with gloved hands, tweezers, or other methods to avoid transfer of skin particles and oils l. Use containers to transfer and/or store materials

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SECTION 8 OVERVIEW OF TESTING REQUIREMENTS 8.1 INTRODUCTION The purpose of this section is to provide an overview of the various tests associated with fume hood performance testing in accordance with the American Society of Heating Refrigerating and Air Conditioning Engineers (ASHRAE) Standard 110, Method of Testing Performance of Laboratory Fume Hoods, and the American National Standards Institute (ANSI) Standard Z9.5, Laboratory Ventilation. An overview CANNOT provide all of the exacting requirements of these standards. For this reason, the NEBB Certified FHT Firm SHALL possess copies of the current versions of both of these industry standards in addition to the NEBB Procedural Standard. Another excellent reference material is the ASHRAE Handbook chapter on laboratory spaces. See Appendix D for additional references. The methods and procedures to perform these tests and the results of the tests are a function of the hood types, fume hood sash configuration styles and test setup modes. Thus a brief overview of these parameters is also included in this section.

8.2 TEST SETUP PROCEDURES 8.2.1 FUME HOOD TYPES Fume hoods are manufactured in two basic styles: bench type and walk-in. While most fume hoods are bench type hoods, walk-in hoods are still required where the physical size of the test apparatus cannot be contained in a bench style enclosure. Listed below are the most common types of fume hoods and their applications: Standard: Airflow volume is relatively constant and airflow face velocity varies as a function of sash opening. May be furnished with all sash configurations. Common hood type found for almost all containment applications. Bypass: Airflow volume and airflow face velocity are relatively constant for all sash openings. As opening size changes due to changes in sash position, openings at the top and the bottom of the hood allow the balance of the air to be drawn into the hood while the airflow face velocity remains constant. May be furnished with all sash configurations. Common hood type found in most containment applications. Auxiliary Air: Airflow volume and airflow face velocity are relatively constant. A plenum is located above the face of the hood and a connection is provided to receive air from a secondary source other than environmentally controlled room air. This secondary source can be conditioned or unconditioned air. These hoods are utilized to achieve energy savings. Variable Air Volume: The airflow volume is a function of sash position. May be furnished with all sash configurations. Common hood type found for almost all containment applications. While the above identify the most common fume hood types, fume hoods types also include: process, 31


SECTION 8 OVERVIEW OF TESTING REQUIREMENTS

high-performance, radioisotope, perchloric acid, California, and distillation hoods. All of these fume hood types are simply variations of the four common types previously identified with some modifications. A process hood is basically a standard hood without a sash. ASHRAE also identifies a canopy hood as a type of fume hood. This is really a misnomer as a canopy hood is related to a kitchen style grease hood. Like a kitchen hood, the purpose of a canopy hood is to remove heat not fumes. Again, consult the ASHRAE Handbooks or various manufacturers’ details and submittals data. 8.2.2 FUME HOOD SASH CONFIGURATIONS Fume hood sashes are normally made from safety glass. The purpose of the fume hood sash is twofold: observation and protection. Sash configurations are sometimes identified as sash opening types or sash styles. The wording sash configuration is the most appropriate. Fume hoods can be manufactured in three various sash configurations: horizontal, vertical, and combination. The number of sashes can vary and all sashes may not be operable. Horizontal Sash: In these fume hoods the sash movement is horizontal. The arrangement can be where one or more of the sashes can be opened at any one time and the sashes can be located at any position in the horizontal tracks. Vertical Sash. In these fume hoods the sash movement is vertical. In a vertical sash configuration, there may be one or more sashes and they can be moved completely down for full closed to completely up to full open or any position in between. Combination Sash. As the name implies, the sashes are a combination of vertical and horizontal sashes that serve the fume hood. 8.2.3 TEST SETUP (TEST SETUP MODE) Test Setup is sometimes identified as the Test Setup Mode. Test Setup is defined as the condition that the fume hood will be during the actual test. There are three test setups: As-Manufactured (AM), As-Installed (AI), and As-Used (AU). It is important to note the differences between the three test setups because the various test procedures, reporting and results are unique for each test setup. As-Manufactured (AM): With this test setup, the fume hood is tested at the manufacturer’s facility or under conditions that would replicate those conditions. The hood and work surface shall be void of all process equipment, apparatus and chemicals. As-Installed (AI): With this test setup, the actual fume hood is tested in its installed, operating condition. All supply, exhaust and return air systems are installed, operable and under control. The hood and work surface shall be void of all process equipment, apparatus and chemicals. As-Used (AU): This test setup is the same as the As-Installed setup except the hood is being utilized for actual process work. Experiment equipment, chemicals and processes are being carried out inside the hood while the fume hood performance testing is being performed. This means that all normal operating equipment within the hood shall be activated and operational including items such as all heat and vapor producing appliances, physical obstructions, etc.

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When doing fume hood performance testing in accordance with the NEBB Procedural Standards for Fume Hood Performance Testing, the test setup shall be defined prior to testing. Test setup shall be as specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm.

8.3 ASHRAE STANDARD 110 The Forward of the current ASHRAE 110 Standard states that: “…The performance of a laboratory hood in providing protection for the worker at the face of the hood is strongly influenced by the aerodynamic design of the hood, the method of operation of the hood, the stability of the exhaust ventilation system, the supply ventilation of the laboratory room, the work practices of the user, and by other features of the laboratory in which it is installed. Therefore, there is a need for a performance test that can be used to evaluate the performance of a laboratory hood in the ideal environment and in the field to establish an "as used" performance rating, including the influences of the laboratory arrangement and its ventilation system. This standard defines a reproducible method of testing laboratory hoods. It does not define safe procedures. However, laboratory hoods are considered by many to be the primary safety devices in conducting laboratory operations. There are many important factors in the safe operation of laboratory hoods that are not described in this standard.” There are several things about the ASHRAE standard that should be discussed. ASHRAE 110 DOES define a reproducible method of testing. It clearly defines the requirements for the three unique tests: Airflow Velocity Tests, Airflow Visualization Tests, and Tracer Gas Containment Tests. The ASHRAE standard DOES NOT define Pass/Fail criteria for the Airflow Face Velocity Tests. It DOES provide a Pass/Fail criteria that may, or may not, be subjective, for the Airflow Visualization Tests. And, while it DOES provide a quantitative rating of the Tracer Gas Containment Tests, the standard DOES NOT include an associated Pass/Fail criteria for this these tests. Another feature of the ASHRAE tests is implied. The tests should be performed in order: Airflow Velocity Tests, Airflow Visualization Tests and finally the Tracer Gas Containment Tests. It is somewhat implied that if an unsafe condition exists at any testing level, the subsequent test should NOT be performed until the condition is remedied. As previously stated in Sections 2 and 3, the scope of testing services should be defined by the Design Professional. Where the scope is not defined, the scope shall be as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. The NEBB Fume Hood Performance Testing program and ASHRAE Standard 110 are flexible. A fume hood may be tested for airflow velocity only and a report could be issued with those test results. Not all three tests have to be performed. As an example, an owner/buyer may want to have a fume hood tested for Airflow Face Velocity Tests only and dictate the acceptable criteria for the tests, and / or a procedure that is not in concert with the requirements of NEBB or ASHRAE. The NEBB Certified FHT Firm can perform the tests in accordance with NEBB’s requirements and can issue a certified report documenting the testing performed. As previously stated in Section 8.1, the NEBB Certified FHT Professional shall be familiar with the

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requirements of ASHRAE Standard 110.

8.4 ANSI STANDARD Z9.5 The Forward of the ANSI Z9.5 Standard states that: “This standard describes required and recommended practices for the design and operation of laboratory ventilation systems used for control of exposure to airborne contaminants. It is intended for use by employers, architects, industrial hygienists, safety engineers, Chemical Hygiene Officers, Environmental Health and Safety Professionals, ventilation system designers, facilities engineers, maintenance personnel, and testing and balance personnel. It is compatible with the ACGIH Industrial Ventilation: A Manual of Recommended Practices, ASHRAE ventilation standards, and other recognized standards of good practice.” The ANSI standard is presented in two-column format. The left column states the requirements of the standard as expressed by the use of “shall.” In the right column is a commentary and/or descriptive explanation of the requirements and suggested good practices. The right column contains examples that are expressed by the word “should.” This is same as the language of the NEBB Procedural Standard. Where the ASHRAE standard is very task oriented, the ANSI standard is more results oriented. The ANSI standard has an excellent section on airflow face velocities with suggested criteria. The Forward of the ANSI standard clearly states that “Requirements should be considered minimum criteria and can be adapted to the needs of the User establishment. It is the intent of the standard to allow and encourage innovation provided the main objective of the standard, “control of exposure to airborne contaminants,” is met. Demonstrably equal or better approaches are acceptable. When standard provisions are in conflict, the more stringent applies.” The ANSI standard DOES contain suggested criteria for airflow velocity, but DOES NOT contain any exacting acceptance requirements for airflow velocity. It also DOES NOT contain any acceptance criteria related to the Airflow Visualization Tests. It DOES contain acceptance criteria for the Tracer Gas Containment Tests. The ANSI standard is another excellent reference source for information regarding fume hoods, biosafety cabinets and laboratory ventilation system design.

8.5 PRELIMINARY TEST PROCEDURES The NEBB Certified FHT Professional should plan the work by preparing an agenda prior to performing the various fume hood tests identified in Section 9, 10, 11, and 12. The agenda should include planning for the testing, identifying the required instrumentation and equipment, safety and health issues, owner requirements, etc. The preparatory work should also include a thorough review of the engineering design documents, plans, specifications and submittals. A site visit is advisable to verify that all construction activities are complete, and all necessary systems and equipment are operational. If deficiencies are found, a letter should be sent to the owner/designer identifying the conditions that may preclude proper fume hood testing.

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SECTION 9 AIRFLOW VELOCITY TESTS PROCEDURES 9.1 INTRODUCTION The purpose of these tests is to validate that the average airflow face velocity meets the specified requirements at the required sash configuration. The required sash configuration condition may be dictated by the Owner, the Specifier, local code requirements, or the AHJ. The sash configuration determined by the Airflow Face Velocity Test will determine the operating sash configuration. Prior to conducting the Airflow Velocity Tests, all mechanical ventilation systems serving the space shall be functional and operating in the normal mode. This includes, but is not limited to, the supply, return and exhaust systems, air terminal boxes, air outlets, air inlets, etc. serving the space. The automatic control equipment and building automation systems shall be operational, calibrated, and commissioned. The TAB work shall be completed. Additionally, the operation of the space shall replicate the normal mode of operation during the tests. This would include that all SOP’s are followed relating to safety, hood operation, equipment in operation during the tests, etc. Finally, the Airflow Velocity Tests should be conducted prior to performing the Airflow Visualization Tests and the Tracer Gas Containment Tests.

9.2 AIRFLOW FACE VELOCITY TEST – CONSTANT AIR VOLUME (CAV) FUME HOOD 9.2.1 INSTRUMENTS AND EQUIPMENT 9.2.1.1 Provide airflow velocity measuring instruments that conform to the requirements of Table 4-1. 9.2.1.2 Provide a linear measuring device. 9.2.1.3 Provide an equipment stand. 9.2.2 TEST PROCEDURES (Average Airflow Face Velocity) 9.2.2.1 Set hood to the design opening sash position as specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. Measure the area of the opening. The area shall be determined as follows: Height: Height shall be based on the dimension from the bottom most part of the sash to the work surface located in a straight plane directly beneath the sash for vertical sashes, or the opening between horizontal tracks on horizontal sashes. Width:

Width shall be based on the interior dimensions of the design sash opening.

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SECTION 9 AIRFLOW VELOCITY TEST PROCEDURES

9.2.2.2 Determine a grid pattern of equal areas by dividing the opening into horizontal and vertical dimensions. Each equal area grid location shall be a maximum of one (1) square foot (0.093 m²) with no dimension larger than 13” (330 mm). See Appendix E for an example of the proper method to determine a grid pattern. 9.2.2.3 Place the instrument on the equipment stand and locate the instrument in the center of each grid location in the plane of the sash opening and normal to the plane. All personnel should stand clear of the hood so as not to affect the airflow. 9.2.2.4 Measure and record the airflow face velocities at the center of each grid location. Each grid location shall have a minimum of 20 samples taken at one second intervals. Average the 20 samples at each location to determine the airflow face velocity at each grid location. Report the average of each grid location. 9.2.2.5 The airflow face velocity is determined by averaging the airflow face velocity from each grid location. Report the average airflow face velocity and the highest and lowest grid location average. 9.2.2.6 If the actual average airflow face velocity as determined above does not meet the acceptance criteria as identified in Section 9.2.3, remedial work, if required, shall be as specified in the contract documents or as agreed to between the owner/buyer and the NEBB Certified FHT Firm. 9.2.2.7 For reference and safety purposes, the fume hood airflow face velocity should also be determined at a full open sash position. The procedure to be followed shall be as previously indicated above. 9.2.2.8 It should be noted that the total fume hood exhaust volume is NOT equal to the average airflow face velocity being captured through the sash opening. Additionally, air will enter the hood under the airfoil and may enter the hood through leakage and other openings. 9.2.3 ACCEPTANCE The acceptance criteria shall be as specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. 9.2.4 REPORTING See Section 5.2.8 for reporting requirements.

9.3 AIRFLOW FACE VELOCITY TEST – VARIABLE AIR VOLUME (VAV) FUME HOOD Variable air volume hoods are tested in a similar manner to constant air volume hoods for determining airflow face velocity. Additionally, VAV hoods are also tested to determine response time to return to a near steady-state condition after a change in sash position. Prior to conducting the Airflow Velocity Test for a VAV fume hood, all controls, sensors and components shall be verified as to their operation, calibration and proper sequencing. 9.3.1 INSTRUMENTS AND EQUIPMENT 9.3.1.1 Provide airflow velocity measuring instruments that conform to the requirements of Table 4-1.

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9.3.1.2 Provide a linear measuring device. 9.3.1.3 Provide an equipment stand. 9.3.2 TEST PROCEDURES (Average Airflow Face Velocity) 9.3.2.1 Set hood to the design opening sash position as specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. Measure the area of the opening. The area shall be determined as follows: Height: Height shall be based on the dimension from the bottom most part of the sash to the work surface located in a straight plane directly beneath the sash for vertical sashes, or the opening between horizontal tracks on horizontal sashes. Width:

Width shall be based on the interior dimensions of the design sash opening.

9.3.2.2 Determine a grid pattern of equal areas by dividing the opening into horizontal and vertical dimensions. Each equal area grid location shall be a maximum of one (1) square foot (0.093 m²) with no dimension larger than 13” (330 mm). See Appendix E for an example of the proper method to determine a grid pattern. 9.3.2.3 Place the instrument on the equipment stand and locate the instrument in the center of each grid location in the plane of the sash opening and normal to the plane. All personnel should stand clear of the hood so as not to affect the airflow. 9.3.2.4 Measure and record the airflow face velocities at the center of each grid location. Each grid location shall have a minimum of 20 samples taken at one second intervals. Average the 20 samples at each location to determine the airflow face velocity at each grid location. 9.3.2.5 The airflow face velocity is determined by averaging the airflow face velocity from each grid location. Report the average airflow face velocity and the highest and lowest grid location average. 9.3.2.6 If the actual average airflow face velocity as determined above does not meet the acceptance criteria as identified in Section 9.3.4, remedial work, if required, shall be as specified in the contract documents or as agreed to between the owner/buyer and the NEBB Certified FHT Firm. 9.3.2.7 For reference and safety purposes, the fume hood airflow face velocity should also be determined at a full open sash position. The procedure to be followed shall be as previously indicated above. 9.3.2.8 Reduce the sash position to 50% of the specified opening and repeat airflow face velocity measurements/calculations as described above. Record the average airflow face velocity at the 50% opening position. 9.3.2.9 Reduce the sash position to 25% of the specified opening and repeat airflow face velocity measurements/calculations as described above. Record the average airflow face velocity at the 25% opening position. 9.3.2.10 It should be noted that the total fume hood exhaust volume is NOT equal to the average

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airflow face velocity being captured through the sash opening. Additionally, air will enter the hood under the airfoil and may enter the hood through leakage and other openings. 9.3.3 TEST PROCEDURES (Response Time) There are two acceptable methods to perform and measure VAV Speed of Response Tests: exhaust duct airflow velocity or hood plenum airflow velocity. Determine the baseline and response conditions by either of the following methods: a. Exhaust duct airflow velocity method: Place the sensing device in a stable (non-turbulent airflow) location of the exhaust duct, or b. Fume hood plenum airflow velocity method: Place sensing device in the fume hood plenum behind the baffle panel in a stable (non-turbulent airflow) location. See Appendix B for proper locations. 9.3.3.1 Measure the velocity at the operating sash opening to establish a baseline condition. 9.3.3.2 The Response Time Test involves 3 cycles of opening and closing the sash position from full closed to the operating sash opening. When changing the sash position, use a smooth continuous motion and move the sash at a rate of approximately 1.5 feet per second (0.45 m/s). 9.3.3.3 Close the sash completely, start velocity measurements recording and leave closed for 30 seconds. Open the sash to the operating sash opening for 60 seconds. Close the sash for 30 seconds. Open the sash to the operating opening for 60 seconds. Close the sash for 30 seconds. Open the sash to the operating sash opening for 60 seconds and then stop velocity measurement recording. 9.3.3.4 Measure and record velocity readings at one second intervals. 9.3.3.5 Measure, record and report the VAV Speed of Response Time to first obtain a velocity equal to 90% of baseline condition for each iteration. 9.3.3.6 Measure, record and report the VAV Time to Steady State to maintain the velocity to within ±10% of baseline condition for each iteration. 9.3.3.7 Perform measurements for all 3 cycles. The procedure stated above applies to either vertical or horizontal sash configurations. For fume hoods with combination sash configurations, the procedure shall be performed both in the vertical and in the horizontal sash opening positions. 9.3.3.8 The repeatability of the results shall be analyzed for all three cycles by determining the relative range of the response times for all three cycles. The relative range is the comparison of the lowest response time and highest response time to the average response time. It shall be calculated as follows: 9.3.3.8.1

Low Value of Range: Divide the minimum response time by the average response time.

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9.3.3.8.2 9.3.3.8.3 9.3.3.8.4


High Value of Range: Divide the maximum response time by the average response time. Relative Range: The range from the Low Value of Range to the High Value of Range. Repeatability: The difference from the Low Value of Range to the High Value of Range

All of the above values shall be reported as percentages. See Appendix E for an example of the test reporting. 9.3.4 ACCEPTANCE The acceptance criteria for the speed of response time, time to steady state, and the repeatability shall be as specified in the contract documents or as agreed to between the Owner / Buyer and the NEBB Certified FHT Firm. 9.3.5 REPORTING See Section 5.2.9 for reporting requirements.

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SECTION 10 AIRFLOW VISUALIZATION TESTS PROCEDURES 10.1 INTRODUCTION The purpose of these tests is to visually verify the fume hood airflow patterns. As with the Airflow Velocity Tests described in Section 9, all mechanical ventilation systems serving the space shall be functional and operating in the normal mode. This includes, but is not limited to, the supply, return and exhaust systems, air terminal boxes, air outlets, air inlets, etc. serving the space. The automatic control equipment and building automation systems shall be operational, calibrated, and commissioned. The TAB work shall be completed. Additionally, the operation of the space shall replicate the normal mode of operation during the tests. This would include that all SOP’s are followed relating to safety, hood operation, quantity of equipment in operation during the tests, etc. Finally, the Airflow Velocity Tests should be completed prior to performing the Airflow Visualization Tests and the Airflow Visualization Tests should be completed prior to performing the Tracer Gas Containment Tests.

10.2 AIRFLOW VISUALIZATION TESTS – LOCAL CHALLENGE The purpose of the test is to provide a visual indication of the fume hood’s capture performance with a small smoke challenge. Care should be taken to insure that the testing personnel’s presence and procedures will not influence the results of this test or that the challenge selected does not produce the flow quantity, volume or momentum such that the visual observations might be affected by the challenge. The Local Challenge Test should be performed prior to performing the Large Volume Challenge Test. Coordinate disabling the local fire alarm system when performing this test. Care should be taken to compensate for smoke discharge velocity and exposure outside of the fume hood. The smoke source shall be as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. In all cases, the NEBB FHT Firm shall have written approval from the Owner, Designer, or AHJ before using a particular smoke source. 10.2.1 INSTRUMENTS AND EQUIPMENT 10.2.1.1 Provide a small smoke source that meet the requirements of Table 4-1. 10.2.1.2 Provide a video recorder that meets the requirements of Table 4-1. (Optional) 10.2.2 TEST PROCEDURES 10.2.2.1 Set the sash position to operating condition as determined by the Airflow Face Velocity Test. 10.2.2.2 Place the smoke source outside the fume hood and under the airfoil. Move along the entire length of the opening. Verify that the smoke is drawn into the hood, properly exhausted and not 41


SECTION 10 AIRFLOW VISUALIZATION TEST PROCEDURES

entrained in a vortex at the top of the hood. 10.2.2.3 Position the smoke source along the sides and bottom of the hood in the sash plane opening. For combination, or horizontal sash fume hoods, pass smoke source along the inside edge of all openings. Verify that the smoke is drawn into the hood and exhausted properly. 10.2.2.4 Place the smoke source 6” (152 mm) inside the hood along the bottom of, and parallel to, the sash. Move along the entire length of the sash bottom. Verify that the smoke is contained within the hood and properly exhausted. 10.2.2.5 Move the smoke source so that it traverses the entire work surface and around internal equipment when applicable. Verify that the smoke is contained within the hood and properly exhausted. 10.2.2.6 Place the smoke source outside the fume hood and determine effects of room and HVAC system conditions by observing the smoke patterns. 10.2.2.7 Place smoke source in cavity above the hood opening and observe the smoke roll inside the hood. 10.2.2.8 For VAV system fume hoods, close all sashes and traverse the smoke source around the sash perimeter, under the airfoil and at the bypass intake above the sash. Verify that air is not escaping the hood around the sash perimeter and all smoke is drawn into the hood under the airfoil and at the bypass intake. 10.2.3 ACCEPTANCE Smoke shall be contained within the fume hood under all test procedures. If the smoke escapes the fume hood under any of the above test procedures, the hood fails and shall be so noted in the report. The NEBB Certified FHT Firm shall immediately notify the Owner / Buyer in writing that a hood has failed. 10.2.4 REPORTING See Section 5.2.10 for reporting requirements.

10.3 AIRFLOW VISUALIZATION TEST – LARGE VOLUME CHALLENGE The Large Volume Challenge Test SHOULD NOT be performed if the hood failed the Local Challenge Test. The purpose of the Large Volume Challenge Test is to provide a visual indication of the fume hood’s capture performance when a large scale challenge is introduced. The test procedures for the Large Volume Challenge Test are similar to the Local Challenge Test. Coordinate disabling the local fire alarm system when performing this test. Care should be taken to compensate for smoke discharge velocity and exposure outside of the fume hood. The smoke source shall be as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. In all cases, the NEBB FHT Firm shall have written approval from the Owner, Designer, or AHJ before using a particular smoke source. 10.3.1 INSTRUMENTS AND EQUIPMENT 10.3.1.1 Provide a large smoke source that meets the requirements of Table 4-1.

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10.3.1.2 Provide a video recorder that meets the requirements of Table 4-1. (Optional) 10.3.2 TEST PROCEDURES 10.3.2.1 Set the sash position to operating condition as determined by the Airflow Face Velocity Test. 10.3.2.2 Place the smoke source outside the fume hood and under the airfoil. Move along the entire length of the opening. Verify that the smoke is drawn into the hood, properly exhausted and not entrained in a vortex at the top of the hood. 10.3.2.3 Discharge the smoke source as close to the sash plane as practical for containment and maximum observation time. Position the smoke source along the sides and bottom of the hood. For combination, or horizontal sash fume hoods, pass smoke source along the inside edge of all openings. Verify that the smoke is drawn into the hood and exhausted properly. 10.3.2.4 Discharge the smoke source as close to the sash plane as practical for containment and maximum observation time. Place the smoke source inside the hood along the bottom of, and parallel to, the sash. Verify that the smoke is contained within the hood and properly exhausted. 10.3.2.5 Move the smoke source so that it traverses the entire work surface and around internal equipment when applicable. Verify that the smoke is contained within the hood and properly exhausted. 10.3.2.6 Place the smoke source outside the fume hood and determine effects of room and HVAC system conditions by observing the smoke patterns. 10.3.2.7 Place smoke source in cavity above the hood opening and observe the smoke roll inside the hood. 10.3.2.8 For VAV system fume hoods, place the smoke source within the fume hood and close all sashes. Flood the interior of the fume hood with the smoke source and verify that the smoke is contained within the hood and exhausted properly. 10.3.2.8 Observe the smoke patterns for containment tests from the side of the hood face. 10.3.3 ACCEPTANCE Smoke shall be contained within the fume hood under all test procedures. If the smoke escapes the fume hood under any of the above test procedures, the hood fails and shall be so noted in the report. The NEBB Certified FHT Firm shall immediately notify the Owner / Buyer in writing that a hood has failed. 10.3.4 REPORTING See Section 5.2.11 for reporting requirements.

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SECTION 11 TRACER GAS CONTAINMENT TESTS PROCEDURES 11.1 INTRODUCTION The purpose of these tests is to verify the fume hood’s containment performance. As with the Airflow Velocity Tests described in Section 9 and the Airflow Visualization Tests described in Section 10, all mechanical ventilation systems serving the space shall be functional and operating in the normal mode. This includes, but is not limited to, the supply, return and exhaust systems, air terminal boxes, air outlets, air inlets, etc. serving the space. The automatic control equipment and building automation systems shall be operational, calibrated, and commissioned. The TAB work shall be completed. Additionally, the operation of the space shall replicate the normal mode of operation during the tests. This would include that all SOP’s are followed relating to safety, hood operation, quantity of equipment in operation during the tests, etc. A Room Layout Drawing shall be prepared for each tested item. The drawing shall identify, but not limited to, the following: a. b. c. d.

Walls Doors Fume hood(s), Other environmental enclosures such as bio-safety cabinets, laminar flow hoods, canopy hoods, etc. e. Location and airflow pattern of all air supply, return and exhaust grilles, registers and diffusers.

Finally, Tracer Gas Containment Tests should only be performed after the Airflow Velocity Tests and the Airflow Visualization Tests are successfully completed.

11.2 TRACER GAS CONTAINMENT TESTS When performing the Tracer Gas Containment Tests, the NEBB Certified FHT Firm must establish the test setup (AM, AI, AU). See Section 8 for descriptions. Fume hood size and sash configuration will also affect the number of sample locations for these tests. The most widely utilized tracer gas is sulfur hexaflouride (SF6). Other gases may be utilized as the tracer gas, but they should be of the same approximate molecular weight and stability as that of sulfur hexaflouride The tracer gas shall be as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. In all cases, the NEBB FHT Firm shall have written approval from the Owner, Designer, or AHJ before using a particular tracer gas.

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SECTION 11 TRACER GAS CONTAINMENT TEST PROCEDURES

Perform a field calibration of the detection instrument and the ejector system in accordance with manufacturer’s recommendations prior to performing each tracer gas test session. Perform a field verification of the detection instrument calibration at the end of the test session using a known concentration of tracer gas. It is recommended that the detection instrument be periodically subjected to a low level concentration of tracer gas as the test session progresses to verify instrument functionality. If the verification test fails, re-calibrate the detection instrument and perform the tracer gas test session again. A test session shall be defined as any time the detection instrument is powered up and down. While the test procedures identified below are based on using SF6, there may be some slight variances based on the use of another tracer gas. 11.2.1 INSTRUMENTS AND EQUIPMENT 11.2.1.1 Provide a detection instrument w/calibrator that meets the requirements of Table 4-1. 11.2.1.2 Provide an ejector system w/calibrator or bubble gauge that meets the requirements of Table 41. 11.2.1.3 Provide a tracer gas that meets the requirements of Table 4-1 and Section 11.2 11.2.1.4 Provide a mannequin that meets the requirements of Table 4-1. 11.2.1.5 Provide a data logger that meets the requirements of Table 4-1. 11.2.1.6 Provide a video recorder that meets the requirements of Table 4-1. (Optional) 11.2.2 TEST PROCEDURES (Static Mode) 11.2.2.1 Set the sash position to operating condition as determined by the Airflow Face Velocity Test. If the test is performed at conditions other than full open, it is suggested that this test should also be performed at full open sash position to determine the effect of misuse or conditions during equipment setup or loading. 11.2.2.2 Perform a background measurement test of the room concentration levels at a representative location. If during the test a steady increase in the sample readings is noted, perform background measurements to assist in determining the source. 11.2.2.3 All dimensions identified below in locating the ejector system are meant to indicate the near edge of the ejector base. The ejector system shall be located 6” (152 mm) behind the sash for all test locations. This places the detection sensor / sensing tube 9” (229 mm) from the ejector. If this location cannot be accomplished due to equipment placement or other obstructions, move the ejector system and move the detection sensor / sensing tube to a suitable location that will maintain the 9” (229 mm) spacing, or as close as possible to the 9” (229 mm) spacing. Use the following method to identify the ejector system locations: a. Vertical Sash: Three (3) locations are required for fume hood 8’ (2.4 m) or less: 12” (304 mm) from the left wall, 12” (304 mm) from the right wall and in the center. Four (4) locations are required for fume hoods greater than 8’ (2.4 m): 12” (304 mm) from the left wall, 12” (304 mm) left of center line, 12” (304 mm) right of center line and 12” (304 mm) from the right wall.

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b. Horizontal Sash: Centerline of each design and/or maximum opening space as previously determined in the Airflow Velocity Tests. c. Combination Sash: Locations shall be determined by both the vertical and horizontal sash configurations described above. 11.2.2.4 Place the ejector system inside the fume hood at the first location. 11.2.2.5 The mannequin shall be directly in front of the ejector system at each test location. The detection sensor/sensing tube shall be located in the breathing zone of the mannequin at a distance of 9” (229 mm) from the near edge of the ejector system typically 3” (76 mm) from the face of the sash and 22” (559 mm) above the work surface. 11.2.2.6 Release the tracer gas at the rate as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. If a release rate has not been specified, then the release rate shall be 4 l/m. Wait 30 seconds before taking samples. 11.2.2.7 Record samples every second for a duration of 5 minutes. 11.2.2.8 Proceed to the next test location and repeat procedure. 11.2.2.9 Report all of the individual readings, the average and the peak concentration for each test location. 11.2.2.10 The performance rating is the highest average of the test locations. Performance Rating shall be reported as follows:

The Static Mode

AM yyy AI yyy AU yyy Where yyy is the highest average concentration of the test locations in ppm. See Appendix E for an example of the test reporting. 11.2.3 ACCEPTANCE (Static Mode) Acceptance ratings for the Static Mode Tests shall be as specified in the contract documents or as agreed to between the Owner / Buyer and the NEBB Certified FHT Firm. Where acceptance ratings have not been defined, the average concentration shall be no greater than those specified in ANSI Z9.5 and shall be as follows: 0.050 ppm for AM at a release rate of 4 l/m 0.100 ppm for AI at a release rate of 4 l/m 0.100 ppm for AU at a release rate of 4 l/m Results should also be evaluated by Owner’s / Buyer’s properly trained personnel for acceptable rating. 11.2.4 REPORTING (Static Mode) See Section 5.2.12 for reporting requirements.

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11.2.5 TEST PROCEDURES (Sash Movement Effect) 11.2.5.1 All dimensions identified below in locating the ejector system are meant to indicate the near edge of the ejector base. The ejector system shall be located 6” (152 mm) behind the sash and shall be located in the center of the fume hood. This places the detection sensor / sensing tube 9” (229 mm) from the ejector. If this location cannot be accomplished due to equipment placement or other obstructions, move the ejector system and the detection sensor / sensing tube to a suitable location that will maintain the 9” (228 mm) spacing. 11.2.5.2 The mannequin shall be directly in front of the ejector system at each test location. The detection sensor/sensing tube shall be located in the breathing zone of the mannequin at a distance of 9” (229 mm) from the near edge of the ejector system typically 3” (76 mm) from the face of the sash and 22” (559 mm) above the work surface. 11.2.5.3 Release the tracer gas at the rate as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. If a release rate has not been specified, then the release rate shall be 4 l/m. 11.2.5.4 The Sash Movement Effect Test involves 3 cycles of opening and closing the sash position from full closed to operating position. When changing the sash position, use a smooth continuous motion and move the sash at a rate of approximately 1.0 to 1.5 feet per second (0.30 to 0.45 m/s). 11.2.5.5 Close the sash completely, start recording and leave closed for 60 seconds. Open the sash to the operating position for 60 seconds. Close the sash for 60 seconds. Open the sash to the operating position for 60 seconds. Close the sash for 60 seconds. Open the sash to the operating position for 60 seconds and then stop recording. 11.2.5.6 For combination hoods, testing shall be performed in both the vertical and in the horizontal positions. 11.2.5.7 Record samples every second continuously for all three cycles. 11.2.5.8 Calculate the 45 second rolling average for each cycle. Record the maximum rolling average associated with each opening of the sash. The Sash Movement Effect Performance Rating shall be reported as follows: SME – AM yyy SME – AI yyy SME – AU yyy Where yyy is the maximum rolling average tracer gas concentration in ppm. See Appendix E for an example of the calculations and the reporting. 11.2.6 ACCEPTANCE Acceptance ratings for the Sash Movement Effect (SME) may be as specified in the contract documents or as agreed to between the owner / buyer and the NEBB Certified FHT Firm. Report the performance rating as indicated above. Results should also be evaluated by Owner’s/Buyer’s properly trained personnel for acceptable ratings.

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11.2.7 REPORTING See Section 5.2.12 for reporting requirements. 11.2.8 TEST PROCEDURES (Perimeter Scan) 11.2.8.1 Open the sash to the same operating position utilized when performing the Static Mode Test as described above. 11.2.8.2 Place the ejector system in the center of the of the work surface (center from left to right and center from the sash plane to the baffle). 11.2.8.3 Remove the mannequin from the front of the fume hood. Remove the detection sensor/sensing tube from the mannequin. 11.2.8.4 Release the gas at the rate as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. If a release rate has not been specified, then the release rate shall be 4 l/m. Release the gas for 30 seconds prior to scanning. 11.2.8.5 While holding the detection sensor/sensing tube in your hand, scan the perimeter of the sash opening and below the airfoil at a rate of not more than 3”/sec (76 mm/sec). Detection sensor/sensing tube shall be passed 1” (25 mm) from the outside surface of the fume hood. 11.2.8.6 Record any measurable leakage and report the location and magnitude. See Appendix E for an example of the test reporting. 11.2.9 ACCEPTANCE Acceptance ratings for the Perimeter Scan may be as specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. Report the results as indicated above. Results should also be evaluated by Owner’s/Buyer’s properly trained personnel for acceptable results. 11.2.10 REPORTING See Section 5.2.12 for reporting requirements.

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SECTION 12 OPTIONAL TESTS AND PROCEDURES 12.1 INTRODUCTION As previously stated in Section 8.3, the NEBB Fume Hood Performance Testing program is flexible. The required scope of work shall be as specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm and may differ from the testing requirements of this NEBB Procedural Standard and / or ASHRAE Standard 110. The NEBB Certified FHT Firm shall be capable of performing any of the fume hood performance tests identified in the NEBB Procedural Standards for Fume Hood Performance Testing. The NEBB Certified FHT Firm shall also be capable of performing a variation of these tests. This may include, but is not limited to, portions of these tests, or tests that may stipulate different procedures and/or reporting requirements. The NEBB Certified FHT Firm is capable of providing a certified report that identifies the measured data and the results of the tests.

12.2 OTHER TESTS AND PROCEDURES When reporting the results of non-standard tests, the NEBB Certified FHT Firm shall clearly indicate in the report the unique procedures followed for the test.

12.3 SUPPLEMENTARY TESTS AND PROCEDURES In addition to variations of standard tests, a stated scope of work may also require the NEBB Certified FHT Firm to perform other supplementary tests such as: a) b) c) d) e)

Room Airflow Velocity Tests Temperature/Humidity Uniformity Tests Sound and Vibration Level Tests Cross Draft Condition Tests Other Tests

If any other tests are required, the test instrumentation, test procedures, acceptance criteria and reporting shall be specified in the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. 12.3.1 ROOM AIRFLOW VELOCITY TESTS Room airflow velocity tests may be performed to determine the velocity pattern(s) of the air being supplied to a space, or the air being returned or exhausted from a space. This test may be utilized as a diagnostic tool when trouble shooting a project where containment enclosures such as fume hoods are not performing adequately due to poor air distribution layout.

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SECTION 12 OPTIONAL TESTS AND PROCEDURES

When performing this test, the NEBB Certified FHT Firm should follow the procedures and requirements as identified in the current edition of the NEBB Procedural Standards for Certified Testing of Cleanrooms. 12.3.2 TEMPERATURE/HUMIDITY UNIFORMITY TESTS Temperature and/or humidity uniformity tests may be performed to determine the temperature and/or humidity gradient that may exist in a space. This test may be utilized as a diagnostic tool when trouble shooting a project where excessive temperature and/or humidity differentials may exist and could effect the results of the process being conducted in a containment enclosure. When performing this test, the NEBB Certified FHT Firm should follow the procedures and requirements as identified in the current edition of the NEBB Procedural Standards for Certified Testing of Cleanrooms. 12.3.3 SOUND AND VIBRATION LEVEL TESTS Sound level tests may be performed to determine the overall sound pressure levels in an operating space. Vibration level tests may be performed to determine vibration magnitude levels of rotating equipment that may be in, or adjacent to an operating space. These tests may be performed as an adjunct test to normal fume hood performance testing or may be used as a diagnostic tool when trouble shooting a project where sound and/or vibration levels may be excessive. When performing these tests, the NEBB Certified FHT Firm should follow the procedures and requirements as identified in the current edition of the NEBB Procedural Standards for Measurement of Sound and Vibration. 12.3.4 CROSS DRAFT CONDITION TESTS Cross draft condition tests may be performed to document the performance of the fume hood’s containment ability when external draft conditions are present. Laboratory/Cleanroom designers and the installing contractors should be aware of the impact of the items such as: a. b. c. d.

The location of the fume hood in the space Location of doors whose opening and closing may cause a draft condition The location of overhead supply, return and exhaust air devices may affect the draft conditions The relative adjacency of other containment devices

The NEBB Certified FHT Firm is required to prepare a layout drawing of the space prior to testing the fume hood tracer gas tests (See Section 11.1) that identifies these components. The fume hood performance may be acceptable to the somewhat static conditions described in Sections 9, 10 and 11 while these standard tests are performed and yet may not provide adequate containment when subjected to unusual, or artificially, created conditions. These draft tests may include testing the performance in concert with a cross-draft, down-draft, or back-draft condition. Additionally, a test designed to simulate the action of personnel walking across the face of the hood during its operation may also display an unsafe condition. The purpose of all of these draft tests is to make the owner/ operators aware of these influences on a fume hood’s performance. The scope of work, the acceptance criteria and the reporting shall be in accordance with the requirements of the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm.

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12.3.5 OTHER TESTS Other tests may also be performed and reported by the NEBB Certified FHT Firm based on the requirements of the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm.

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APPENDIX A SAMPLE FHT SPECIFICATION (This recommended FHT specification is available from www.nebb.org) NEBB recommends that these FHT Specifications be referenced as related documents in other appropriate sections of the project specifications.

SECTION 15990 – FUME HOOD PERFORMANCE TESTING PART 1 - GENERAL 1.1 RELATED DOCUMENTS Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section. This Section includes the performance testing of fume hoods. 1.2 DEFINITIONS Acceptance Criteria: The measured value(s) or range(s) which determine if the results of the test pass or fail. Accuracy: The capability of an instrument to indicate the true value of a measured quantity. AHJ: The local governing Authority Having Jurisdiction over the installation. Air Supply Fixtures: Devices or openings through which air flows into the laboratory room. For the purpose of this standard all accessories, connecting duct adapters, or other mounting airways shall be considered part of the supply fixture and reported as a unit or an assembly. Some specific supply fixtures are defined as follows: grille: a louvered or perforated face over an opening register: a combination grille and damper assembly diffuser: an outlet designed to mix supply air and room air and to distribute it in varying directions perforated ceiling: a ceiling with perforated panels used to distribute the air uniformly throughout the ceiling or a portion of the ceiling. Filter pads may be used to achieve a similar result. Auxiliary Air: Unconditioned or partially conditioned supply or supplemental air delivered to a laboratory at the laboratory fume hood to reduce room air consumption. Calibrate: The act of comparing an instrument of unknown accuracy with a standard of known accuracy to detect, correlate, report, or eliminate by adjustment any variation in the accuracy of the tested instrument. Control Level: The average measured concentration of tracer gas, in parts of tracer gas per million parts of air by volume (ppm), that is not exceeded at the hood face with a 4.0 Lpm release rate. I


APPENDIX A SAMPLE FHT SPECIFICATION

Deficiency: Any circumstance or operation that affects the measurement results as compared to the design criteria required by the contract documents. Design Sash Opening: The position of the sash at which the design team assumes that the fume hood will be operating. Face Velocity: The average velocity of air moving perpendicular to the hood face, usually expressed in feet per minute (fpm) or meters per second (m/s). Fume Hood (sometimes referred to as a laboratory hood): A box-like structure enclosing a source of potential air contamination, normally with one open or partially open side, into which air is moved for the purpose of containing and exhausting air contaminants. A fume hood is generally used for bench-scale laboratory operations but does not necessarily involve the use of a bench or table. Fume Hood System: An arrangement consisting of a fume hood, its adjacent room environment, and the air exhaust equipment, such as blowers and ductwork, required to make the hood operable. Function: For the purposes of this NEBB Standard, function refers to the specific type of data measurement specified in Section 4, Standards for Instrumentation and Calibration. High Value of Range: The maximum response time divided by the average response time of the VAV Response Time Test. Value is expressed as a percentage. Hood Face: The plane of minimum area at the front portion of a laboratory fume hood through which air enters when the sash(es) is (are) fully opened, usually in the same plane as the sash for a hood with a vertical sash. For a hood with horizontal sash(es) or a combination sash, the hood face is usually the plane passing through the midpoint between the inner and outer sashes. Lazy Airflow: Airflow within the hood is described as lazy when smoke remains on the work surface without smoothly flowing to the back baffle. LPM: Liters per minutes. Low Value of Range: The minimum response time divided by the average response time of the VAV Response Time Test. Value is expressed as a percentage. May: Used to indicate a course of action that is permissible as determined by the NEBB Certified FHT Firm. Maximum Sash Opening: The position of the sash at which the fume hood has the largest opening. N/A: Not Available, Not Applicable, or Not Accessible. The simple notation “N/A” without definition is not allowed. NEBB Certified FHT Firm: A NEBB Certified FHT Firm is a firm that has met and maintains all the requirements of the National Environmental Balancing Bureau for firm certification in Fume Hood Performance Testing and is currently certified by NEBB. A NEBB Certified FHT Firm shall employ at least one NEBB Certified FHT Professional in a full time management position.

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NEBB Certified FHT Report: The data presented in a NEBB Certified FHT Report accurately represents system measurements obtained in accordance with the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing. A NEBB Certified FHT Report does not necessarily guarantee that systems measured conform to the design requirements or stated guidelines. The report is an accurate representation of the measured results only. NEBB Certified FHT Professional: A NEBB Certified FHT Professional is a full time employee of the firm in a management position who has successfully passed the professional level written and practical qualification examinations and maintains the Ceretified Professional re-certification requirements of NEBB. Operating Sash Opening: The position of the sash at which the fume hood user places the sash while working at the face of the fume hood. The operating sash opening should take into consideration all of the procedures to be conducted in the fume hood. There may be more than one operating sash opening. Performance Rating: Rating definition of the Static Mode Test portion of the Tracer Gas Tests. It is comprised of a series of letters and numbers consisting of the letters AM, AI, or AU, and three-digit number: AM yyy AI yyy AU yyy Where: AM indicates the test setup is "As Manufactured," AI indicates the test setup is "As Installed," AU indicates the test setup is "As Used," yyy indicates the control level of tracer gas established by the test in ppm. As an example: A test rating of AU 0.500 would indicate that the fume hood controls the leakage into the laboratory to 0.500 ppm at the mannequin's sensing point with a tracer gas release rate of 4.0 Lpm. Positional Sash Movement Effect Control Level: The maximum 45-second moving average of the tracer gas concentration observed during a series of sash movement tests at one ejector and mannequin position. Positional Control Level: The average tracer gas concentration at a position during a test. Precision: The ability of an instrument to produce repeatable readings of the same quantity under the same conditions. The precision of an instrument refers to its ability to produce a tightly grouped set of values around the mean value of the measured quantity. PPM: Parts per million. Procedure: The approach to and execution of a sequence of work operations to yield a repeatable and defined result. Range: The upper and lower limits of an instrument’s ability to measure the value of a quantity for which the instrument is calibrated.

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Relative Range: The range from the Low Value of Range to the High Value of Range. Reported as percentages. Release Rate: The rate of release, in actual liters (litres) per minute (Lpm), of tracer gas during a hood test. Repeatability: The difference from the Low Value of Range to the High Value of Range. Reported as a percentage. Resolution: The smallest change in a measured variable that an instrument can detect. Reverse Flow: Airflow within the hood when smoke released in the hood moves forward toward the front of the hood. This term does not apply to the forward motion of the roll inside the hood that occurs in the upper cavity of the hood above the hood opening or to the cyclonic motion that occurs behind a closed horizontal sash. Roll: The rotation of air, commonly referred to as vortex, in the upper cavity of the hood. The roll is induced by the momentum of the air entering the hood through the hood opening. Sash Movement Effect: The maximum of the positional sash movement effects for all the positions tested on a particular hood. Sash Movement Effect Performance Rating: Rating definition of the Sash Movement Effect Test portion of the Tracer Gas Tests. It is comprised of a series of letters and numbers consisting of the letters SME-AM, SME-AI, or SME-AU, and three-digit number: SME-AM yyy SME-AI yyy SME-AU yyy Where: SME means "sash movement effect," AM indicates the test setup was "As Manufactured," AI indicates the test setup was "As Installed," AU indicates the test setup was "As Used," yyy equals the sash movement effect, in ppm. For example: A test rating of SME-AI 10.0, indicates the fume hood was tested in the “AsInstalled” test setup and that the maximum 45-second rolling average concentration of tracer gas measured during a sash movement test was 10.0 ppm with a tracer gas release rate of 4.0 Lpm . Shall: The term is used to indicate mandatory requirements that must be followed in order for the project to become a NEBB certified project. Work must conform to these standards and procedures and no deviation is permitted. Note: In the event unique circumstances prevent a required action from being fulfilled, a notation shall be included in the FHT report explaining the reason that the requirement was not completed. For example, such notation could be one of the following: Not Available, Not Applicable, or Not Accessible. The simple notation “N/A” without definition is not allowed.

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Should: The term is used to indicate that a certain course of action is preferred but not necessarily required. Specified Rating: The hood performance rating as specified, proposed, or guaranteed either in the purchase of the hood or in the design and construction of the laboratory, or both. Standard: A required qualification, action, or result for FHT work. Standard Operating Procedure: An internal policy prepared by the each FHT firm and / or prepared by the Owner/Buyer. Procedures are written to provide guidance, direction, and step-by-step details relating to issues such as safety, testing protocols, acceptance criteria, etc. NEBB FHT Firm SOP’s shall be utilized in an absence of SOP’s prepared by the Owner. Test Sash Opening: The position or positions of the sash at which the fume hood is tested. Test Setup (Test Setup Mode): Defines the condition of the fume hood being tested. There are three distinct conditions that the fume hood may be tested: As-Manufactured (AM): With this test setup, the fume hood is tested at the manufacturer’s facility or under conditions that would replicate those conditions. The hood and work surface shall be void of all process equipment, apparatus and chemicals. As-Installed (AI): With this test setup, the actual fume hood is tested in its installed, operating condition. All supply, exhaust and return air systems are installed, operable and under control. The hood and work surface shall be void of all process equipment, apparatus and chemicals. As-Used (AU): This test setup is the same as the As-Installed setup except the hood is being utilized for actual process work. Experiment equipment, chemicals and processes are being carried out inside the hood while the fume hood performance testing is being performed. This means that all normal operating equipment within the hood shall be activated and operational including items such as all heat and vapor producing appliances, physical obstructions, etc. Testing: The use of specialized and calibrated instruments to measure fluid quantities, temperatures, pressures, rotational speeds, electrical characteristics, velocities, and sound and vibration levels, Testing, Adjusting, and Balancing (TAB): A systematic process or service applied to heating, ventilating and air-conditioning (HVAC) systems and other environmental systems to achieve and document air and hydronic flow rates. The standards and procedures for providing these services are addressed in the current edition of the NEBB “PROCEDURAL STANDARDS FOR THE TESTING, ADJUSTING AND BALANCING OF ENVIRONMENTAL SYSTEMS.” VAV Speed of Response: The time, measured from the first movement of the sash, for the VAV system to restore the slot velocity or airflow to 90 percent of the average steady-state value. VAV Time to Steady State: The time, measured from the first movement of the sash, for the VAV system restore and maintain the average slot velocity of airflow between 90 and 110 percent of the average steady-state value. Work Surface: The surface that the fume hood sets on.

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1.3 FHT FIRM QUALIFICATIONS The FHT Firm shall be NEBB Certified in Fume Hood Performance Testing. The individual conducting the fume performance testing shall be a NEBB Certified FHT Professional. 1.4 FHT FIRM SUBMITTALS 1.4.1 Qualification Data: When requested, submit 2 copies of evidence that the FHT firm and this Project's FHT team members meet the qualifications specified in Sub-section 1.3 FHT Firm Qualifications. 1.4.2 FHT Agenda: When requested, submit 2 copies of the FHT Agenda. Include a complete set of report forms intended for use on this Project. 1.4.3 Certified FHT Reports: Submit a final FHT report in accordance with the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing. 1.5 QUALITY ASSURANCE 1.5.1 The NEBB Certified FHT Firm shall submit 2 copies of the firm's NEBB FHT Certification. 1.5.2 When requested, the NEBB Certified FHT Firm shall provide the NEBB Certificate of Conformance Certification. 1.5.3 FHT Report Forms: Prepare report forms in accordance with the requirements from the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing. 1.5.4 Instrumentation Calibration: Calibration of instruments shall be in accordance with the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing. 1.6 CONSTRUCTION TEAM RESPONSIBILITY TO FHT AGENCY 1.6.1 Provide the NEBB Certified FHT Firm with a conformed set of contract documents (drawings, specifications, and approved submittals), including all current approved change orders/contract modifications. 1.6.2 Develop a project schedule with the input of the NEBB Certified FHT Firm that coordinates the work of other disciplines and provides adequate time in the construction process to allow successful completion of the FHT work. 1.6.3 Notify the NEBB Certified FHT Firm of schedule changes. 1.6.4 Ensure that the building enclosure is complete, including but not limited to, all structural components, windows and doors installed, door hardware complete, ceilings complete, stair, elevator and mechanical shafts complete, roof systems complete, all plenums sealed, etc. 1.6.5 Complete the installation of permanent electrical power systems serving the HVAC equipment and systems. Such systems shall be properly installed in accordance with all applicable codes to ensure the safety of all construction personnel. 1.6.6 Complete the installation of all HVAC equipment and systems to ensure safe operation.

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1.6.7 Perform the startup of all HVAC equipment and systems in accordance with the manufacturer’s recommendations. 1.6.8 Complete installation, programming (including design parameters and graphics), calibration, and startup of all building control systems. 1.6.9 Verify that the building control system provider has commissioned and documented their work before the FHT work begins. 1.6.10 Require that the building control system firm provide access to hardware and software, or onsite technical support required to assist the FHT effort. The hardware and software or the onsite technical support shall be provided at no cost to the NEBB Certified FHT Firm. 1.6.11 Furnish and install all drive changes as required. 1.6.12 Complete all TAB work prior to performing FHT work. 1.7 FHT INSTRUMENTATION AND EQUIPMENT The FHT Firm shall provide all necessary instrumentation, equipment and appurtenances required to perform the fume hood performance testing. All instrumentation, equipment and appurtenances shall be as indicated in the current edition of the NEBB Procedural Standards for Fume Hood Performance Testing.

PART 2 - PRODUCTS (Not Applicable) PART 3 – EXECUTION 3.1 EXAMINATION Examine the Contract Documents to become familiar with Project requirements and to discover conditions in systems' designs that may preclude proper FHT of systems and equipment. Contract Documents are defined in the General and Supplementary Conditions of the Contract. Report deficiencies discovered. The NEBB Certified FHT Firm shall verify that the TAB work is complete and shall review the completed TAB Report prior to performing any fume hood tests. 3.2 GENERAL PROCEDURES FOR FUME HOOD PERFORMANCE TESTING Perform hood testing on each fume hood indicated to be tested according to the procedures contained in the current edition of the NEBB Procedural Fume Hood Performance Testing and this section. 3.3 TEST SETUP MODE All fume hoods shall be tested in the select one (As-Manufactured, As-Installed or As-Used) test setup mode. 3.4 DESIGN SASH OPENING (The design professional must select the appropriate design sash opening for each hood and each type of hood i.e. horizontal sash, vertical sash, or combination sash. The following may be used as a guide in selecting the design sash opening:

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Vertical Sash Horizontal Sash Combination Sash


18” above the work surface One sash fully open, all other sashes closed(3 sash), or two sashes fully open and two sashes fully closed( 4 sash) One sash fully open to 18” above the work surface and all other sashes closed.

If the design professional is unsure about selecting the appropriate sash design sash opening, the owner should be consulted. It is imperative to specify the design sash opening, as the fume hood performance tests are based on this sash position.) The design sash opening shall be _(insert height)____” above the work surface for vertical sash fume hoods, or The design sash opening shall be _(insert number of sashes)_____sashes open for horizontal sash fume hoods, or The design sash opening shall be __(insert height)____” above the work surface and ___(insert number of sashes)_____ open for combination sash fume hoods. 3.5

AIRFLOW VELOCITY TESTS: Constant Air Volume (CAV) Fume Hood 3.5.1

Test Procedures: Airflow Face Velocity Tests

3.5.1.1 Set hood to the design opening sash position or as agreed to by the Owner / Buyer. Measure the area of the opening. The area shall be determined as follows: Height shall be based on the dimension from the bottom most part of the sash to the work surface located in a straight plane directly beneath the sash for vertical sashes, or the opening between horizontal tracks on horizontal sashes. Width: Width shall be based on the interior dimensions of the design sash opening. 3.5.1.2 Determine a grid pattern of equal areas by dividing the opening into horizontal and vertical dimensions. Each equal area grid location shall be a maximum of one (1) square foot (0.093 m²) with no dimension larger than 13” (330 mm). 3.5.1.3 Place the instrument on the equipment stand and locate the instrument in the center of each grid location in the plane of the sash opening and normal to the plane. All personnel should stand clear of the hood so as not to affect the airflow. 3.5.1.4 Measure and record the airflow face velocities at the center of each grid location. Each grid location shall have a minimum of 20 samples taken at one second intervals. Average the 20 samples at each location to determine the airflow face velocity at each grid location. 3.5.1.5 The hood airflow face velocity is determined by averaging the airflow face velocity from each grid location. Report the hood average airflow face velocity and the highest and lowest grid location average. 3.5.1.6 If the actual average airflow face velocity as determined above does not meet the acceptance criteria as Section 3.5.2, remedial work, if required, is NOT part of the fume hood testing scope of work. If authorized, the remedial work could be performed by the NEBB Certified FHT Firm as an additional service.

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3.5.1.7 For reference and safety purposes, the fume hood airflow face velocity should also be determined at a full open sash position. The procedure to be followed shall be as previously indicated above. 3.5.1.8 It should be noted that the total fume hood exhaust volume is NOT equal to the average airflow face velocity being captured through the sash opening. Additionally, air may enter the hood through leakage and other openings. 3.5.2 Acceptance Criteria: The acceptance criteria for CAV airflow face velocity shall be select one: 100 fpm ±10 fpm As directed by the Owner / Buyer Define acceptance criteria if other than 100 fpm 3.5.3 Reporting Requirements The following shall be included in the final report: a. b. c. d. e. f. g. h. 3.6

Technician Name Date of test Sash Configuration Design Opening Sash Position (Height and Width) Average Airflow Velocity at each grid location (fpm) (m/s) Hood average Airflow Face Velocity (fpm) (m/s) Test instrumentation Acceptance Criteria

AIRFLOW VELOCITY TESTS: Variable Air Volume (VAV) Fume Hood 3.6.1 Test Procedures: Airflow Face Velocity Tests 3.6.1.1 Set hood to the design opening sash position or as agreed to by the Owner / Buyer. Measure the area of the opening. The area shall be determined as follows: Height shall be based on the dimension from the bottom most part of the sash to the work surface located in a straight plane directly beneath the sash for vertical sashes, or the opening between horizontal tracks on horizontal sashes. Width: Width shall be based on the interior dimensions of the design sash opening. 3.6.1.2 Determine a grid pattern of equal areas by dividing the opening into horizontal and vertical dimensions. Each equal area grid location shall be a maximum of one (1) square foot (0.093 m²) with no dimension larger than 13” (330 mm). 3.6.1.3 Place the instrument on the equipment stand and locate the instrument in the center of each grid location in the plane of the sash opening and normal to the plane. All personnel should stand clear of the hood so as not to affect the airflow. 3.6.1.4 Measure and record the airflow face velocities at the center of each grid location. Each grid location shall have a minimum of 20 samples taken at one second intervals. Average the 20 samples at each location to determine the airflow face velocity at each grid location.

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3.6.1.5 The hood airflow face velocity is determined by averaging the airflow face velocity from each grid location. Report the hood average airflow face velocity and the highest and lowest grid location average. 3.6.1.6 If the actual average airflow face velocity as determined above does not meet the acceptance criteria as Section 3.4.2, remedial work, if required, is NOT part of the fume hood testing scope of work. If authorized, the remedial work could be performed by the NEBB Certified FHT Firm as an additional service. 3.6.1.7 For reference and safety purposes, the fume hood airflow face velocity should also be determined at a full open sash position. The procedure to be followed shall be as previously indicated above. 3.6.1.8 Reduce the sash position to 50% of the specified opening and repeat airflow face velocity measurements / calculations as described above. Record the average airflow face velocity at the 50% opening position. 3.6.1.9 Reduce the sash position to 25% of the specified opening and repeat airflow face velocity measurements / calculations as described above. Record the average airflow face velocity at the 25% opening position. 3.6.1.10 It should be noted that the total fume hood exhaust volume is NOT equal to the average airflow face velocity being captured through the sash opening. Additionally, air may enter the hood through leakage and other openings. 3.6.2

Test Procedures: Response Test

3.6.2.1 There are two acceptable methods to perform and measure response time: exhaust duct airflow velocity or hood plenum airflow velocity. Determine the baseline and response conditions by either of the following methods: a. Exhaust duct airflow velocity method: Place the sensing device in a stable (nonturbulent airflow) location of the exhaust duct, or b. Fume hood plenum airflow velocity method: Place sensing device in the fume hood plenum behind the baffle panel. 3.6.2.2 Measure the velocity at the full sash opening to establish a baseline condition. 3.6.2.3 The Response Time Test involves 3 cycles of opening and closing the sash position from full closed to full open. When changing the sash position, use a smooth continuous motion and move the sash at a rate of approximately 1.5 feet per second (0.45 m/s). 3.6.2.4 Close the sash completely, start velocity measurements recording and leave closed for 30 seconds. Open the sash to full opening for 60 seconds. Close the sash for 30 seconds. Open the sash to full opening for 60 seconds. Close the sash for 30 seconds. Open the sash to full opening for 60 seconds. Close the sash for 30 seconds and stop velocity measurements recording. 3.6.2.5 Measure and record velocity readings at one second intervals.

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3.6.2.6 Measure, record and report the speed of response to first obtain a velocity equal to 90% of baseline condition for each iteration. 3.6.2.7 Measure, record and report the time to maintain the velocity to within ±10% of baseline condition for each iteration. 3.6.2.8 Perform measurements for all 3 cycles. The procedure stated above applies to either vertical or horizontal sash configurations. For fume hoods with combination sash configurations, the procedure shall be performed both in the vertical and in the horizontal sash opening positions. 3.6.2.9 The repeatability of the results should be analyzed for all three cycles by determining the relative range of the response times for all three cycles. The relative range is the comparison of the lowest response time and highest response time to the average response time. It may be calculated as follows: 3.2.6.9.1 3.2.6.9.2 3.2.6.9.3 3.2.6.9.4

Low Value of Range: Divide the minimum response time by the average response time. High Value of Range: Divide the maximum response time by the average response time. Relative Range: The range from the Low Value of Range to the High Value of Range. Repeatability: The difference from the Low Value of Range to the High Value of Range

All of the above values shall be reported as percentages. 3.6.3

Acceptance Criteria:

3.6.3.1

The acceptance criteria for VAV airflow face velocity shall be select one: 100 fpm ±10 fpm As directed by the Owner / Buyer Define acceptance criteria if other than 100 fpm

3.6.3.2

The acceptance criteria for average speed of response, individual speed of responses, individual times to maintain, Low Value of Range, High Value of Range, Relative Range and Repeatability shall be select one: As directed by the Owner / Buyer Define criteria for all of the reporting criteria

3.6.4 Reporting Requirements The following shall be included in the final report: a. b. c. d. e. f. g.

Technician Name Date of test Sash Configuration Design Opening Sash Position (Height and Width) Average Airflow Velocity at each grid location (fpm) (m/s) Hood average Airflow Face Velocity (fpm) (m/s) Test results reported at 25%, 50% and 100% of specified conditions

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NEBB FHT PROCEDURAL STANDARDS h. i. j. k. l. m. n. o. p.


Speed of Response (in seconds) (3 cycles) Low Value of Range (in percentage) High Value of Range (in percentage) Relative Range (in percentage) Repeatability (in percentage) Time to Maintain (in seconds) (3 cycles) Test Method (exhaust airflow velocity method or fume hood plenum airflow velocity method) Test instrumentation Acceptance Criteria

3.7 AIRFLOW VISUALIZATION TESTS: Local Challenge The purpose of the Local Challenge Test is to provide a visual indication of the fume hood’s capture performance when a small scale challenge is introduced. Coordinate disabling the local fire alarm system when performing this test. Care should be taken to compensate for smoke discharge velocity and exposure outside of the fume hood. 3.7.1 Test Procedures 3.7.1.1 Set the sash position to operating condition as determined by the Airflow Face Velocity Test. 3.7.1.2 Place the smoke source outside the fume hood and under the airfoil. Move along the entire length of the opening. Verify that the smoke is drawn into the hood, properly exhausted and not entrained in a vortex at the top of the hood. 3.7.1.3 Position the smoke source along the sides and bottom of the hood in the sash plane opening. For combination, or horizontal sash fume hoods, pass smoke source along the inside edge of all openings. Verify that the smoke is drawn into the hood and exhausted properly. 3.7.1.4 Place the smoke source 6” (152 mm) inside the hood along the bottom of, and parallel to, the sash. Move along the entire length of the sash bottom. Verify that the smoke is contained within the hood and properly exhausted. 3.7.1.5 Move the smoke source so that it traverses the entire work surface and around internal equipment when applicable. Verify that the smoke is contained within the hood and properly exhausted. 3.7.1.6 Place the smoke source outside the fume hood and determine effects of room and HVAC system conditions by observing the smoke patterns. 3.7.1.7 Place smoke source in cavity above the hood opening and observe the smoke roll inside the hood. 3.7.2 Acceptance Criteria Smoke shall be contained within the fume hood under all test procedures. If the smoke escapes the fume hood under any of the above test procedures, the hood fails and shall be so noted in the report. The NEBB Certified FHT Firm shall immediately notify the Owner / Buyer in writing that the fume hood has failed. 3.7.3

Reporting Requirements

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The following shall be included in the final report: a. Technician Name b. Date of test c. Test State d. Sash Configuration e. Sash Opening Height and Width f. Challenge Medium Used g. Narrative description of actual visual test results including Statement of Pass/Fail h. Test instrumentation i. Acceptance Criteria 3.8 AIRFLOW VISUALIZATION TESTS: Large Volume Generation The Large Volume Challenge Test SHOULD NOT be performed if the hood failed the Local Challenge Test. The purpose of the Large Volume Challenge Test is to provide a visual indication of the fume hood’s capture performance when a large scale challenge is introduced. The test procedures for the Large Volume Challenge Test are similar to the Local Challenge Test. Coordinate disabling the local fire alarm system when performing this test. Care should be taken to compensate for smoke discharge velocity and exposure outside of the fume hood. 3.8.1 Test Procedures 3.8.1.1 Set the sash position to operating condition as determined by the Airflow Face Velocity Test. 3.8.1.2 Place the smoke source outside the fume hood and under the airfoil. Move along the entire length of the opening. Verify that the smoke is drawn into the hood, properly exhausted and not entrained in a vortex at the top of the hood. 3.8.1.3 Discharge the smoke source as close to the sash plane as practical for containment and maximum observation time. Position the smoke source along the sides and bottom of the hood. For combination, or horizontal sash fume hoods, pass smoke source along the inside edge of all openings. Verify that the smoke is drawn into the hood and exhausted properly. 3.8.1.4 Discharge the smoke source as close to the sash plane as practical for containment and maximum observation time. Place the smoke source inside the hood along the bottom of, and parallel to, the sash. Verify that the smoke is contained within the hood and properly exhausted. 3.8.1.5 Move the smoke source so that it traverses the entire work surface and around internal equipment when applicable. Verify that the smoke is contained within the hood and properly exhausted. 3.8.1.6 Place the smoke source outside the fume hood and determine effects of room and HVAC system conditions by observing the smoke patterns. 3.8.1.7 Place smoke source in cavity above the hood opening and observe the smoke roll inside the hood. 3.8.1.8 Try to observe smoke patterns for containment tests from the side of the hood face.

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3.8.2 Acceptance Criteria Smoke shall be contained within the fume hood under all test procedures. If the smoke escapes the fume hood under any of the above test procedures, the hood fails and shall be so noted in the report. The NEBB Certified FHT Firm shall immediately notify the Owner / Buyer in writing that the fume hood has failed. 3.8.3 Reporting Requirements The following shall be included in the final report: a. b. c. d. e. f. g. h. i. 3.9

Technician Name Date of test Test State Sash Configuration Sash Opening Height and Width Challenge Medium Used Narrative description of actual visual test results including Statement of Pass/Fail Test instrumentation Acceptance Criteria

TRACER GAS CONTAINMENT TESTS: Static Mode 3.9.1 Test Procedures 3.9.1.1 Set the sash position to operating condition as determined by the Airflow Face Velocity Test. If the test is performed at conditions other than full open, it is suggested that this test should also be performed at full open sash position to determine the effect of misuse or condition during equipment setup or loading. 3.9.1.2 Perform a background measurement test of the room concentration levels at a representative location. If during the test a steady increase in the sample readings is noted, perform background measurements to assist in determining the source. 3.9.1.3 All dimensions identified below in locating the ejector system are meant to indicate the near edge of the ejector base. The ejector system shall be located 6” (152 mm) behind the sash for all test locations. This places the detection sensor / sensing tube 9” (229 mm) from the ejector. If this location cannot be accomplished due to equipment placement or other obstructions, move the ejector system and move the detection sensor / sensing tube to a suitable location that will maintain the 9” (229 mm) spacing, or as close as possible to the 9” (229 mm) spacing. Use the following method to identify the ejector system locations: a. Vertical Sash: Three (3) locations are required for fume hood 8’ (2.4 m) or less: 12” (304 mm) from the left wall, 12” (304 mm) from the right wall and in the center. Four (4) locations are required for fume hoods greater than 8’ (2.4 m): 12” (304 mm) from the left wall, 12” (304 mm) left of center line, 12” (304 mm) right of center line and 12” (304 mm) from the right wall. b. Horizontal Sash: Centerline of each maximum opening space as previously determined in the Airflow Velocity Tests. c. Combination Sash: Locations shall be determined by both the vertical and horizontal sash configurations described above. 3.9.1.4

Place the ejector system inside the fume hood at the first location.

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3.9.1.5 The mannequin shall be directly in front of the ejector system at each test location. The detection sensor / sensing tube shall be located in the breathing zone of the mannequin at a distance of 9” (229 mm) from the near edge of the ejector system typically 3” (76 mm) from the face of the sash and 22” (558 mm) above the work surface. 3.9.1.6 Release the tracer gas at the rate as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. If a release rate has not been specified, then the release rate shall be 4 l/m. Wait 30 seconds before taking samples. 3.9.1.7

Record samples every second for a duration of 5 minutes.

3.9.1.8 Proceed to the next test location and repeat procedure. 3.9.1.9 Report all of the individual readings, the average and the peak concentration for each test location. 3.9.1.10 The performance rating is the highest average of the test locations. The Static Mode Performance Rating shall be reported as follows: AM yyy AI yyy AU yyy Where yyy is the highest average concentration of the test locations in ppm. 3.9.2 Acceptance Criteria Acceptance ratings for the Static Mode Tests shall be as directed by the Owner / Buyer. Where acceptance ratings have not been defined, the average concentration shall be no greater than those specified in ANSI Z9.5 and shall be as follows: 0.05 ppm for AM at a release rate of 4 l/m 0.10 ppm for AI at a release rate of 4 l/m 0.10 ppm for AU at a release rate of 4 l/m Results will be evaluated by Owner’s / Buyer’s properly trained personnel for acceptable rating. 3.9.3 Reporting Requirements The following shall be included in the final report: a. b. c. d. e. f. g. h. i. j. k.

Technician Name Date of test Test State Sash Configuration Sash Opening Height and Width Room Layout Drawing Graphical display of each test Tracer Gas Release Rate Test Instrumentation Report individual readings, the average and peak at each sample location Report the Performance Rating and compare to the Acceptance Rating. Tests results that exceed acceptance ratings shall be noted in the report.

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3.10 TRACER GAS CONTAINMENT TESTS: Sash Movement Effect 3.10.1 Test Procedures 3.10.1.1 All dimensions identified below in locating the ejector system are meant to indicate the near edge of the ejector base. The ejector system shall be located 6” (152 mm) behind the sash and shall be located in the center of the fume hood. This places the detection sensor / sensing tube 9” (228 mm) from the ejector. If this location cannot be accomplished due to equipment placement or other obstructions, move the ejector system and the detection sensor / sensing tube to a suitable location that will maintain the 9” (228 mm) spacing. 3.10.1.2 The mannequin shall be directly in front of the ejector system at each test location. The detection sensor / sensing tube shall be located in the breathing zone of the mannequin at a distance of 9” (228 mm) from the near edge of the ejector system typically 3” (76 mm) from the face of the sash and 22” (558 mm) above the work surface. 3.10.1.3 Release the tracer gas at the rate as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. If a release rate has not been specified, then the release rate shall be 4 l/m. 3.10.1.4 Start with the sash in the closed position for 60 seconds. Open the sash to the same operating position utilized when performing the Static Test as described above. The sash shall remain open for 60 seconds. Close the sash for 60 seconds. Repeat the process for two additional cycles. 3.10.1.5 The sash should be opened and closed with a smooth motion at a rate of 1.0 to 1.5 feet per second (0.30 to 0.45 m/s). 3.10.1.6 For combination hoods, testing shall be performed in both the vertical and in the horizontal positions. 3.10.1.7 Record samples every second continuously for all three cycles. 3.10.1.8 Calculate the 45 second rolling average for each cycle. Record the maximum rolling average associated with each opening of the sash. The Sash Movement Effect Performance Rating shall be reported as follows: SME – AM yyy SME – AI yyy SME – AU yyy Where yyy is the maximum rolling average tracer gas concentration in ppm. 3.10.2 Acceptance Criteria Acceptance ratings for the Sash Movement Effect (SME) shall be as directed by the owner / buyer. Report the performance rating as indicated above. Results will be evaluated by Owner’s/Buyer’s properly trained personnel for acceptable ratings 3.10.3 Reporting Requirements The following shall be included in the final report:

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NEBB FHT PROCEDURAL STANDARDS a. b. c. d. e. f. g. h. i. j. k. l. m.


Technician Name Date of test Time of test Test State Sash Configuration Sash Opening Height and Width Room Layout Drawing Graphical display of each test Tracer Gas Release Rate Test Instrumentation Record the maximum 45 second rolling average associated with each opening of the sash. Report the Sash Movement Performance Rating. If Acceptance Rating has been defined, test results that exceed acceptance rating shall be noted in the report.

3.11 TRACER GAS CONTAINMENT TESTS: Perimeter Scan 3.11.1 Test Procedures 3.11.1.1 Open the sash to the same operating position utilized when performing the Static Test as described above. 3.11.1.2 Place the ejector system in the center of the fume hood. 3.11.1.3 Remove the mannequin from the front of the fume hood. Remove the detection sensor / sensing tube from the mannequin. 3.11.1.4 Release the gas at the rate as specified in the contract documents or as agreed to between the Owner and the NEBB Certified FHT Firm. If a release rate has not been specified, then the release rate shall be 4 l/m. Release the gas for 30 seconds prior to scanning. 3.11.1.5 While holding the detection sensor / sensing tube in your hand, scan the perimeter of the sash opening and below the airfoil at a rate of not more than 3”/sec (76 mm/sec). Detection sensor / sensing tube shall be passed 1” (25 mm) from the outside surface of the fume hood. 3.11.1.6 Record any measurable leakage and report the location and magnitude. 3.11.2 Acceptance Criteria Acceptance ratings for the Perimeter Scan shall be as directed by the Owner / Buyer. Report the results as indicated above. Results will be evaluated by Owner’s / Buyer’s properly trained personnel for acceptable results. 3.11.3 Reporting Requirements The following shall be included in the final report: a. b. c. d.

Technician Name Date of test Time of test Test State

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NEBB FHT PROCEDURAL STANDARDS e. f. g. h. i. j. k. l. m.


Sash Configuration Sash Opening Height and Width Room Layout Drawing Graphical display of each test Tracer Gas Release Rate Test Instrumentation Record any measurable leakage Report the location and magnitude of the leakage If Acceptance Rating has been defined, test results that exceed acceptance rating shall be noted in the report.

3.12 OTHER TESTS Edit or delete as applicable to project requirements: In addition to variations of standard tests, a stated scope of work may also require the NEBB Certified FHT Firm to perform other supplementary tests such as: a) b) c) d) e)

Room Airflow Velocity Tests Temperature/Humidity Uniformity Tests Sound and Vibration Level Tests Cross Draft Condition Tests Other Tests

If these other tests are required, the test instrumentation, test procedures, acceptance criteria and reporting shall be specified below or as directed by the Owner/Buyer. All costs associated with these tests are to be included with the scope of work. The tests shall be specified in a similar format as utilized above. 3.12.1 Test Procedures 3.12.2 Acceptance Criteria 3.12.3 Reporting Requirements The following is provided in guidance in specifying these other tests: 3.12.2 ROOM AIRFLOW VELOCITY TESTS Room airflow velocity tests may be performed to determine the velocity pattern(s) of the air being supplied to a space, or the air being returned or exhausted from a space. This test may be utilized as a diagnostic tool when trouble shooting a project where containment enclosures such as fume hoods are not performing adequately due to poor air distribution layout. When performing this test, the NEBB Certified FHT Firm should follow the procedures and requirements as identified the current edition of the NEBB Procedural Standards for Certified Testing of Cleanrooms. 3.12.3 TEMPERATURE/HUMIDITY UNIFORMITY TESTS Temperature and/or humidity uniformity tests may be performed to determine the temperature and /or humidity gradient that may exist in a space. This test may be utilized as a diagnostic tool when trouble shooting a project where excessive temperature and/or humidity differentials may exist and could effect the results of the process being conducted in a containment enclosure.

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When performing this test, the NEBB Certified FHT Firm should follow the procedures and requirements as identified the current edition of the NEBB Procedural Standards for Certified Testing of Cleanrooms. 3.12.4 SOUND AND VIBRATION LEVEL TESTS Sound level tests may be performed to determine the overall sound pressure levels in an operating space. Vibration level tests may be performed to determine vibration magnitude levels of rotating equipment that may be in or adjacent to an operating space. These tests may be performed as an adjunct test to normal fume hood performance testing or may be used as a diagnostic tool when trouble shooting a project where sound and/or vibration levels may be excessive. When performing these tests, the NEBB Certified FHT Firm should follow the procedures and requirements as identified the current edition of the NEBB Procedural Standards for Measurement of Sound and Vibration. 3.12.5 CROSS DRAFT CONDITION TESTS Cross draft condition tests may be performed to document the performance of the fume hood’s containment ability when external draft conditions are present. Laboratory / Cleanroom designers and the installing contractors should be aware of the impact of the items such as: a. The location of the fume hood in the space. b. Location of doors whose opening and closing may cause a draft condition. c. The location of overhead supply, return and exhaust air devices may affect the draft conditions d. The relative adjacency of other containment devices. The NEBB Certified FHT Firm is required to prepare a layout drawing of the space prior to testing the fume hood tracer gas tests (See Section 11.1) that identifies these components. The fume hood performance may be acceptable to the somewhat static conditions described in Sections 9, 10 and 11 while these standard tests are performed and yet may not provide adequate containment when subjected to unusual, or artificially, created conditions. These draft tests may include testing the performance in concert with a cross-draft, down-draft, or back-draft condition. Additionally, a test designed to simulate the action of personnel walking across the face of the hood during its operation may also display an unsafe condition. The purpose of all of these draft tests is to make the owner / operators aware of these influences on a fume hood’s performance. The scope of work, the acceptance criteria and the reporting shall be in accordance with the requirements of the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. 3.12.6 OTHER TESTS Other tests may also be performed and reported by the NEBB Certified FHT Firm based on the requirements of the contract documents or as agreed to between the Owner/Buyer and the NEBB Certified FHT Firm. 3.13 FINAL REPORT The final report shall be in accordance with the requirements of the current edition of the NEBB Procedural Standards for the Fume Hood Performance Testing.

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XX

APPENDIX B EXAMPLE TEST ILLUSTRATIONS The examples and illustrations presented in this appendix are meant to provide guidance in performing the various Fume Hood Performance Tests. B.1 FUME HOOD AIRLFOW VELOCITY TESTS – VAV RESPONSE TEST The purpose of the VAV Response Test is to quantify the time required for the mechanical exhaust system serving the fume hood to return to its design control point after the sash position has been changed from a steady state condition. The VAV Response Test involves 3 complete cycles of opening and closing the sash position from full closed to full open and concurrently measuring the associated changes in airflow velocity. The sash should be moved using a smooth continuous motion. There are two components associated with this test: VAV Speed of Response Time VAV Time to Steady State Section 9.3.3 identifies the testing procedure requirements. There are two acceptable methods to perform and measure response times. Both methods involve the measurement of airflow velocity. The airflow velocity can be measured either in the exhaust duct or in the fume hood plenum. Figure B-1 illustrates the acceptable sensing device locations which are as follows: a. Exhaust duct airflow velocity method: Place the sensing device in a stable (non-turbulent airflow) location of the exhaust duct, or b. Fume hood plenum airflow velocity method: Place sensing device in the fume hood plenum behind the baffle panel. When utilizing the exhaust duct location, the sensing device should be located in a long, straight run of hard duct approximately 4 to 5 diameters downstream of any offsets, elbows or other obstructions. Additionally, the sensing device should be located at least 1 to 2 diameters upstream of any offsets, elbows or other obstructions. When utilizing the fume hood plenum location, the sensing device should be located in the rear exhaust plenum through an opening in the interior exhaust baffles. The sensor should be positioned so as to read flow being exhausted through the top of the hood if directional probe is utilized with a consistent velocity reading during initial setup procedure.

XXI


APPENDIX B EXAMPLE TEST ILLUSTRATIONS

Figure B – 1: VAV Response Test Setups

XXII



B.2 TRACER GAS CONTAINMENT TESTS The purpose of the Tracer Gas Containment Tests is to verify the fume hood’s containment performance. Figure B-2 illustrates the correct spatial arrangement of the mannequin and the ejector system for the Static Mode Test and the Sash Movement Effect Test.

3” 75mm HORIZ. SASH

6” 150mm

Figure B – 2: Mannequin and Ejector Position

XXIII



XXIV

APPENDIX C EJECTOR SYSTEM SPECIFICATIONS

Figure C – 1: Figure C – 2: Figure C – 3: Figure C – 4: Figure C – 5: Figure C – 6:

Ejector System (US Units) Ejector System (SI Units) Ejector – General Arrangement (US Units) Ejector – General Arrangement (SI Units) Critical Orifice (US Units) Critical Orifice (SI Units)

XXV


Figure C – 1: Ejector System (US Units)


XXVI


Figure C – 2: Ejector System (SI Units)


XXVII


Figure C – 3: Ejector – General Arrangement (US Units)


XXVIII


Figure C – 4: Ejector – General Arrangement (SI Units)


XXIX


Figure C – 5: Critical Orifice (US Units)


XXX


Figure C – 6: Critical Orifice (SI Units)


XXXI



XXXII

APPENDIX D REFERENCES AND REFERENCED PUBLICATIONS A.

Air Movement Control Association International, Inc. (AMCA) 30 West University Drive, Arlington Heights, IL 60004 AMCA Publication 201-2002 , Fan Application Manual AMCA Publication 203-1990, Field Performance Measurement of Fan Systems Both publications contain engineering fundamentals of fan application, design and performance ratings and field measurements.

B.

American Industrial Hygiene Association (AIHA) 2700 Prosperity Avenue, Suite 250, Fairfax, VA 22031 ANSI/AIHA Standard Z9.5-2003, Laboratory Ventilation Contains information on the recommendations, design, installation, and maintenance of laboratory ventilation systems.

C.

American Conference of Governmental industrial Hygienists (ACGIH) Kemper Meadow Drive, Cincinnati, Ohio 45240 ACGIH Publication: Industrial Ventilation, A Manual of Recommended Practice Contains information on the design and installation of industrial ventilation systems and exhaust systems and hoods.

D.

American Society of Heating, Air Conditioning and Refrigerating Engineers (ASHRAE) 1791 Tullie Circle Northeast, Atlanta, Georgia 30329 ASHRAE Handbook—HVAC Applications (2007) Chapter 7—Health Care Facilities Chapter 14—Laboratory Systems Chapter 16—Clean Spaces ANSI/ASHRAE Standard 110, Method of Testing Performance of Laboratory Fume Hoods

E.

National Environmental Balancing Bureau (NEBB) 8575 Grovemont Circle, Gaithersburg, Maryland 20877-4121 E.1 Environmental Systems Technology Contains information on HVAC system history and fundamentals, engineering principles, system design, equipment components and installation, testing and balancing, controls, acoustics, and an extensive glossary and set of engineering tables and charts. E.2 Procedural Standards for Testing, Adjusting, and Balancing of Environmental Systems—2005 A "how-to" set of procedural standards that provide systematic methods for testing, adjusting, and balancing (TAB) of HVAC systems includes sections on TAB instruments and calibration, report forms, and sample specification. E.3 Testing, Adjusting, Balancing Manual for Technicians—1997 A practical field-use manual for balancing technicians designed to be used for reference and job site application as well as for training balancing crews. This edition includes a section on mathematics and equations for field use. XXXIII


APPENDIX D REFERENCES AND REFERENCED PUBLICATIONS

E.4 Procedural Standards for Certified Testing of Cleanrooms—2006 This manual provides an extensive array of information on cleanroom testing, technology and test procedures. It includes: cleanroom design; cleanroom systems; laboratory and health facilities; test instruments and test procedures; HEPA filter leak testing; and particle counts. E.5 Study Course for Certified Testing of Cleanrooms A self-study course in cleanrooms and systems including cleanroom testing equipment, control systems, cleanroom test procedures, system and unit test procedures, and cleanroom equipment and accessories. E.6 Procedural Standards for the Measurement of Sound and Vibration—2006 This publication provides background information and step-by-step comprehensive guidance for obtaining and recording sound and vibration data on HVAC systems. Topics include: instrumentation, inspection of building construction and conditions, interior and exterior sound measurement, and vibration measurement procedures. Also covered are sample specifications and report forms. E.7 Sound and Vibration Design and Analysis—1994 A concise coverage of sound and vibration as it relates to HVAC systems. Basic concepts of the science of sound and vibration are covered, plus the most current information on equipment sound levels, duct element regenerated and sound power and attenuation, duct breakout and breakin, sound transmission in indoor and outdoor spaces, and vibration analysis. Includes references and glossary. E.8 Study Course for Measuring Sound and Vibration—1995 A home study course on measuring sound and vibration, it guides the student in an orderly sequence, with diagrams, charts and problems to recognize principles and procedures. E.9 Procedural Standards for Building Systems Commissioning—1999 A manual providing comprehensive guidance for commissioning building HVAC systems. The text describes organization, planning, procedures and methods for verifying and documenting the performance of building systems. Included are a sample specification, model reporting forms, check sheets and functional test checklists, as well as a schematic depicting the commissioning process. G.

National Sanitation Foundation (NSF) 789 N. Dixboro Road, Ann Arbor, Michigan 48106 NSF 49-2005, Class II (Laminar Flow) Biohazard Cabinetry This document applies to cabinetry designed to minimize hazards inherent in work with low and moderate risk biological agents and defines tests which must be passed.

H.

National Fire Prevention Association (NFPA) 1 Batterymarch Park, Quincy, Massachusetts 02169

I.

Scientific Equipment and Furniture Association (SEFA) 1205 Franklin Ave., Ste. 320, Garden City, NY 11530

J.

United States of America, Agencies and Departments US Department of Labor - Occupational Safety & Health Administration 200 Constitution Avenue, NW, Washington, DC 20210

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APPENDIX E ENGINEERING FORMULAS AND EXAMPLES E.1 HVAC ENGINEERING FORMULA (SI UNITS) E.1.1 AIR EQUATIONS A.

V = 1.414 ● (VP/d)½ where V = Velocity d= density, “d” = 3.48 (Pb/T)

B.

V = (1.66 ● VP)½ for Std. air (d = 1.204 kg/m3)

C.

TP = VP + SP

D.

V = VM (d / 1.204)

E.

Airflow Volume (L/s) = 1000 ● Area ● Volume

E.2 HVAC ENGINEERING FORMULA (IP UNITS) E.2.1 AIR EQUATIONS A.

V = 1096 • (VP/d)½ where V = Velocity d= density, “d” = 1.325 (Pb/T)

B.

V = 4005 • (VP)½ for Std. air (d = .075 lbs/ft3)

C.

TP = VP + SP

D.

V = VM (d / 0.075)

E.

Airflow Volume (cfm) = Area ● Volume

XXXV


APPENDIX E ENGINEERING FORMULAS AND EXAMPLES

E.3 METRIC EQUIVALENTS QUANTITY acceleration airflow volumetric flow rate area atmospheric pressure distance, length, or displacement lighting intensity lighting power pressure temperature velocity volume

SYMBOL m/s² m³/s L/s m³/hr m² mm² kPa Bar M M mm Lx lm/m² Lm kPa Pa °C m/s m³

UNIT meters per second squared cubic meters per second liters per second cubic meters per hour square meter square millimeters kiloPascals Barometers meter meter millimeter Lux Lumens/square meter Lumen kiloPascals =1000 Pascals Pascals degrees Celsius meters per second cubic meters

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IP RELATIONSHIP 1 m/s² = 3.281 ft/sec² 1 m³/s = 2118.88 cfm 1 L/s = 2.12 cfm 1 m³/hr = 0.589 cfm 1 m² = 10.76 ft² 1 mm² = 0.0016 in² 101.325 kPa = 29.92 in. Hg = 14.696 psi 1 Bar = 29.92 in. Hg = 14.696 psi 1 m = 3.281 ft. 1 m = 39.37 inches 1 mm = 0.039 inches 1 lx = 0.0929 fc 1 lm/m² = 0.0931 fc 1 Lm = 0.001496 watts 1 kPa = 0.296 in. Hg = 0.145 psi 1 Pa = 0.004015 in.w.g. °C = (°F – 32)/1.8 1 m/s = 196.9 fpm 1 m³ = 35.31 ft³



E.4 AIR DENSITY CORRECTION FACTORS (SI UNITS) Altitude (m)

Sea Level

Barometer (kPa)

Air Temp ºC

0º 20º 50º 75º 100º 125º 150º 175º 200º 225º 250º 275º 300º 325º 350º 375º 400º

250

500

750

1000

1250

1500

1750

2000

2500

3000

101.3

98.3

96.3

93.2

90.2

88.2

85.1

83.1

80.0

76.0

71.9

1.08 1.00 0.91 0.85 0.79 0.74 0.70 0.66 0.62 0.59 0.56 0.54 0.51 0.49 0.47 0.46 0.44

1.22 1.11 1.02 0.96 0.92 0.84 0.77 0.72 0.67 0.62 0.60 0.56 0.53 0.51 0.48 0.44 0.40

1.17 1.07 0.99 0.93 0.88 0.81 0.74 0.70 0.65 0.60 0.57 0.54 0.51 0.49 0.46 0.43 0.39

1.13 1.03 0.95 0.89 0.85 0.78 0.71 0.67 0.62 0.58 0.55 0.52 0.49 0.47 0.45 0.41 0.37

1.09 0.99 0.92 0.86 0.81 0.75 0.69 0.64 0.60 0.56 0.53 0.50 0.47 0.45 0.43 0.39 0.36

1.05 0.95 0.88 0.83 0.78 0.72 0.66 0.62 0.58 0.54 0.51 0.48 0.45 0.44 0.41 0.38 0.35

1.01 0.91 0.85 0.80 0.75 0.69 0.64 0.60 0.56 0.52 0.49 0.46 0.44 0.42 0.40 0.37 0.33

0.97 0.89 0.82 .077 0.73 0.67 0.62 0.58 0.54 0.51 0.48 0.45 0.43 0.41 0.39 0.35 0.32

0.93 0.85 0.79 0.74 0.70 0.65 .060 0.56 0.52 0.49 0.46 0.43 0.41 0.39 0.37 0.34 0.31

0.90 0.82 0.76 0.71 0.68 0.62 0.57 0.54 0.50 .047 0.44 0.42 0.39 0.38 0.35 0.33 0.30

0.87 0.79 0.73 0.69 0.65 0.60 0.55 0.51 0.48 0.45 0.42 0.40 0.38 0.36 0.34 0.32 0.29

Table E-1: Air Density Correction Factors (SI Units) Standard Air Density (Sea Level and 20ºC) = 1.204 kg/m3 at 101.325 kPa

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E.4 AIR DENSITY CORRECTION FACTORS (IP UNITS)

Altitude (ft)

Sea Level

Barometer (in. of Hg.) (in. w.g.)

Air Temp ºF

-40º 0º 40º 70º 100º 150º 200º 250º 300º 350º 400º 450º 500º 550º 600º 700º 800º

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

29.92 407.50

28.86 392.80

27.82 378.60

26.82 365.00

25.84 351.7

24.90 333.90

23.98 326.40

23.09 314.80

22.22 302.10

21.39 291.10

20.58 280.10

1.26 1.15 1.06 1.00 0.95 0.87 0.80 0.75 0.70 0.65 0.62 0.55 0.58 0.53 0.50 0.46 0.42

1.22 1.11 1.02 0.96 0.92 0.84 0.77 0.72 0.67 0.62 0.60 0.56 0.53 0.51 0.48 0.44 0.40

1.17 1.07 0.99 0.93 0.88 0.81 0.74 0.70 0.65 0.60 0.57 0.54 0.51 0.49 0.46 0.43 0.39

1.13 1.03 0.95 0.89 0.85 0.78 0.71 0.67 0.62 0.58 0.55 0.52 0.49 0.47 0.45 0.41 0.37

1.09 0.99 0.92 0.86 0.81 0.75 0.69 0.64 0.60 0.56 0.53 0.50 0.47 0.45 0.43 0.39 0.36

1.05 0.95 0.88 0.83 0.78 0.72 0.66 0.62 0.58 0.54 0.51 0.48 0.45 0.44 0.41 0.38 0.35

1.01 0.91 0.85 0.80 0.75 0.69 0.64 0.60 0.56 0.52 0.49 0.46 0.44 0.42 0.40 0.37 0.33

0.97 0.89 0.82 .077 0.73 0.67 0.62 0.58 0.54 0.51 0.48 0.45 0.43 0.41 0.39 0.35 0.32

0.93 0.85 0.79 0.74 0.70 0.65 .060 0.56 0.52 0.49 0.46 0.43 0.41 0.39 0.37 0.34 0.31

0.90 0.82 0.76 0.71 0.68 0.62 0.57 0.54 0.50 .047 0.44 0.42 0.39 0.38 0.35 0.33 0.30

0.87 0.79 0.73 0.69 0.65 0.60 0.55 0.51 0.48 0.45 0.42 0.40 0.38 0.36 0.34 0.32 0.29

Table E-2: Air Density Correction Factors (U.S. Units) Standard Air Density (Sea Level and 70ºF) = 0.075 lb/ft3 at 29.92 in. Hg.

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E.5


FHT AIRFLOW FACE VELOCITY

E.5.1 DETERMINING A GRID PATTERN The purpose of this section is to determine a sample grid pattern for a fume hood airflow face velocity test. The procedure is identical for both CAV and VAV fume hoods. Sections 9.2.2 and 9.3.2 discuss the requirements for determining a grid pattern. Both sections state the following requirements: “Measure the area of the opening. The area shall be determined as follows: Height: Height shall be based on the dimension from the bottom most part of the sash to the work surface. Width: Width shall be based on the interior dimensions of the design sash opening. Determine a grid pattern of equal areas by dividing the opening into horizontal and vertical dimensions. Each equal area grid location shall be a maximum of one (1) square foot (0.093 m²) with no dimension larger than 13” (330 mm).” A grid pattern is determined in the exact same manner as a duct traverse layout and has the same purpose: To determine the average airflow velocity. While duct traverse measurements are performed in order to calculate the airflow volume (m³/s or cfm) flowing inside of a duct, the focus with fume hoods is strictly to determine the average airflow face velocity. E.5.2 SAMPLE GRID PATTERN DETERMINATION The grid pattern layout and calculations presented in this example are intended to serve as a working illustration of the correct procedures and methods involved in determining the proper grid pattern for all face velocity measurements for all types of fume hoods. For this example we have a 6 ft. (1.8 m) fume hood that has a vertical sash configuration. The width of the interior of the vertical sash is 63” (1.60 m). The design sash opening is 18” (457 mm). You are required to determine the proper grid pattern. According to NEBB requirements, determine a grid pattern of equal areas both vertically and horizontally where the maximum area does not exceed one (1) square foot (0.093 m²) and no dimension exceeds 13” (330 mm). First determine the number of rows of vertical grids. This can be done by taking the vertical dimension and dividing by 13”. # of Vertical Grid Rows = 18” / 13” = 1.38 Consequently, we must have a minimum of 2 vertical grid rows. With two vertical grid rows, the height of each vertical grid will be equal to: Vertical Spacing = 18” / 2 = 9” Since the grids will be 9” apart, the distance from the bottom of the sash to the center of the top grid will be 4.5 and the distance from the work surface to the center of the bottom grid will also be: 18” = 4.5” + 9” + 4.5”

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Second, determine the horizontal grids. Again, no distance can exceed 13” and each grid shall have a maximum of 1 ft². Based on this criterion, the horizontal spacing can be determined by dividing the overall width of the sash opening by 13” Horizontal Columns = 63” / 13” = 4.8 Based on this calculation we must have a minimum of 5 horizontal grids columns. With 5 horizontal grid columns, the width of each horizontal grid will be equal to: Horizontal Spacing = 63” / 5 = 12.6” Since the grids will be 12.6” apart, the distance from the left side of the sash to the center of the first grid will be 6.3” and the distance to the center of each of the next grids will be on 12.6” centers. Thus, the overall grid horizontal grid spacing will be: 63” = (6.3” + 12.6” + 12.6” + 12.6” + 12.6” + 6.3”) Finally, verify that each grid does not exceed 1 ft². Our example resulted with a grid pattern that had 2 vertical rows and 5 columns. Each grid would have an area of 113.4 square inches (9”x12.6” = 113.4 in²), or 0.79 ft² (113.4 /144 = 0.79 ft²). Each grid area does not exceed the 1.00 ft² criteria. The grid pattern shown below in Figure E.5.2.1. as determined from above shows 2 vertical rows and 5 horizontal columns. Each grid in this example is 9” x 12.6”.

FIGURE E 5.2.1

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E.6


FHT MEASURMENT AND REPORTING EXAMPLES

E.6.1 AIRFLOW FACE VELOCITY TEST – VARIABLE AIR VOLUME (VAV) FUME HOOD As stated in Section 9.3.3 for the Response Test: “The repeatability of the results should be analyzed for all three cycles by determining the relative range of the response times for all three cycles. The relative range is the comparison of the lowest response time and highest response time to the average response time.” For the Response Test, the following information is to be calculated and reported: • • • •

Low Value of Range High Value of Range Relative Range Repeatability

These values may be calculated as follows: Average Response Time: Add the response times from each of three cycles and divide by three. Low Value of Range: Divide the minimum response time by the average response time. High Value of Range: Divide the maximum response time by the average response time. Relative Range: State the range from the Low Value of Range to the High Value of Range. Repeatability: The difference from the Low Value of Range to the High Value of Range All of the above values shall be reported as percentages. As an example, the response times for the three cycles are: 4 seconds, 5 seconds and 5 seconds. The Average Response Time is: The Low Value of Range is: The High Value of Range is: The Relative Range is: The Repeatability is:

(4 + 5 + 5)/3 = 4.67 seconds. 4 seconds/4.67 seconds = 86%. 5 seconds/4.67 seconds = 107%. 86% - 107%. 21%.

Note: It is appropriate to report the average time to two decimal places and the various ranges and repeatability values should be rounded off and reported in full percentage points only. E.6.2 TRACER GAS CONTAINMENT (STATIC MODE) As stated in Section 11.2.2 for the Static Mode Test, “The performance rating is the highest average of the test locations. The Static Mode Performance Rating shall be reported as follows: AM yyy AI yyy AU yyy Where yyy is the highest average concentration of the test locations in ppm.” The static mode performance rating contains two components; the test setup and the highest average leak concentration of all the test locations in ppm. As an example, the static mode test is performed on a 6’ vertical sash fume hood. The fume hood Test Setup is As-Installed. Since the fume hood is less than 8’, the static mode test must be performed in

XLI



three locations; 12” from the left wall, 12” from the right wall and in the center. Each set of measurements is averaged and the highest average of the three locations is reported. You have performed the test for each of the required locations and have calculated the following averages: Location: 12” from the left wall 12” from the right wall Center of the fume hood

Average Concentration 0.032 ppm 0.025 ppm 0.081 ppm

The highest average concentration is the center location. Consequently, the static mode test reporting would be as follows: AI 0.081 Note that it is appropriate to report results to three decimal places. Additionally, decimal values should be stated with a zero located in front of the decimal point. This is the manner that metric values are reported and fume hood test results should also be reported in this manner. E.6.3 TRACER GAS CONTAINMENT (SASH MOVEMENT EFFECT) Section 11.2.5 defines the procedures for performing the Sash Movement Effect Test. It states to “Calculate the 45 second rolling average for each cycle. Record the maximum rolling average associated with each opening of the sash. The Sash Movement Effect Performance Rating shall be reported as follows: SME – AM yyy SME – AI yyy SME – AU yyy Where yyy is the maximum rolling average tracer gas concentration in ppm The reporting of the Sash Movement Effect Performance Rating is similar to the Static Mode Performance Rating except that it contains three components; the acronym SME (for Sash Movement Effect), the test setup and the highest average leak concentration in ppm. Additionally, the Sash Movement Effect requires a calculation not a simple reporting of averages. The 45-second rolling average must be calculated for each of the three sash movement cycles from fully closed to fully open. For each cycle, there are 16 individual data sets must be averaged and then “rolled” into a single value. The procedure is as follows: As the sash is moved from closed to open, the time must be noted at the beginning of the sash opening. The 16 individual data sets are as follows: Data Set Number 1 2 3 15 16

Time Span 1 through 45 Seconds 2 through 46 Seconds 3 through 47 Seconds 15 through 59 Seconds 16 through 60 Seconds

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The first time span would include all of the concentration values for seconds 1 through 45. The second time span would include all of the concentration values for seconds 2 through 46. The process continues through the 16th data set which would include the concentration values from second 16 through 60. The average leak concentration for each of the three opening cycles is calculated and the highest average is reported as the Sash Movement Effect Performance Rating. An example will help to illustrate the required calculations and reporting. You are performing the Sash Movement Effect Test you are ready to begin the test. The test procedures require you release the tracer gas and close the sash. You should begin data logging the measurements at this time. The sash is to remain closed for 60 seconds. After 60 seconds, you open the sash to the operating position for 60 seconds. Then, you closed the sash for 60 seconds. You repeated this procedure for 3 complete cycles from fully closed to the operational sash position. The measurements were continuously data logged for the entire test. The data measurements are as shown in Table E.6.3.1. and the 45-Second Rolling Averages have been calculated in Tabled E.6.3.2 below. Table E.6.3.1 Data Measurements: Project Lab Room Number Fume Hood Number

Test date Atomic Laboratories Tested by 101 Joe Smith 101-1 Tracer Gas Concentration (ppm)

1-Jan-09

seconds

closed 1

open 1

close 2

open 2

close 3

open 3

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

start at close 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.651 9.972 8.334 9.924 1.991 0.019 0.017 0.017 0.017 0.016 0.016 0.016 0.016 0.016 0.016 0.016

0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.812 1.004 8.421 9.682 3.691 2.015 0.062 0.019 0.017 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.812 1.004 8.421 9.682 3.691 2.015 0.062 0.019 0.017 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

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seconds 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

closed 1 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

open 1 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016


close 2 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

open 2 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

close 3 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016

The 45-Second Rolling Averages have been calculated in Tabled E.6.3.2 below.

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open 3 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016 0.016



Table E.6.3.2 45-Second Rolling Average Values Time Span 0 – 45 sec 1 – 46 2 – 47 3 – 48 4 – 49 5 – 50 6 – 51 7 – 52 8 – 53 9 – 54 10 – 55 11 – 56 12 – 57 13 – 58 14 – 59 15 – 60

Data Set Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Total Average

Cycle 1 Open 0.700 0.700 0.700 0.700 0.700 0.700 0.700 0.700 0.700 0.686 0.465 0.280 0.060 0.016 0.016 0.016 7.839 0.490

Cycle 2 Open 0.584 0.584 0.584 0.584 0.584 0.584 0.584 0.584

Cycle 3 Open 0.584 0.584 0.584 0.584 0.584 0.584 0.584 0.584

0.567 0.545 0.358 0.143 0.062 0.017 0.016 0.016 6.396 0.400

0.567 0.545 0.358 0.143 0.062 0.017 0.016 0.016 6.396 0.400

Again, The Sash Movement Effect (SME) Performance Rating is the open cycle that has the highest 45 second rolling average. From data in Table E.6.3.2, Cycle 1 has an average of 0.490 ppm of the tracer gas concentration. Based on this data and calculations the Sash Movement Effect Performance Rating for this fume hood will be: SME-AI 0.490

XLV



E.6.4 TRACER GAS CONTAINMENT (PERIMETER SCAN) The Perimeter Scan portion of the Tracer Gas Containment Tests also has some unique reporting requirements. Section 11.2.8 requires that any measurable leakage should be identified in the report and that the location and magnitude should be identified. Figure E.6.4.1 shows a sample report.

Top of sash, 12” from upper left corner (0.45 ppm)

Bottom of sash 39” from lower right corner (0.39 ppm)

Figure E.6.4.1: Sample Perimeter Scan Report Drawing

XLVI

Fume Hood Performance 2

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