14175-3

Documento contenuto nel prodotto UNIEDIL IMPIANTI edizione 2007.2 E' vietato l'uso in rete del singolo documento e la sua riproduzione. E' autorizzata la stampa per uso interno.

NORMA ITALIANA

Cappe di aspirazione

UNI EN 14175-3

Parte 3: Metodi per prove di omologazione

OTTOBRE 2004

Fume cupboards

CLASSIFICAZIONE ICS

71.040.10

SOMMARIO

La norma descrive i metodi per le prove di omologazione aventi lo scopo di valutare la sicurezza e le prestazioni delle cappe di aspirazione.

RELAZIONI NAZIONALI RELAZIONI INTERNAZIONALI

= EN 14175-3:2003 La presente norma è la versione ufficiale in lingua inglese della norma europea EN 14175-3 (edizione dicembre 2003).

ORGANO COMPETENTE

UNICHIM - Associazione per l’Unificazione nel settore dell’Industria Chimica

RATIFICA

Presidente dell’UNI, delibera del 21 settembre 2004

UNI Ente Nazionale Italiano di Unificazione Via Battistotti Sassi, 11B 20133 Milano, Italia

© UNI - Milano Riproduzione vietata. Tutti i diritti sono riservati. Nessuna parte del presente documento può essere riprodotta o diffusa con un mezzo qualsiasi, fotocopie, microfilm o altro, senza il consenso scritto dell’UNI.

UNI EN 14175-3:2004

NORMA EUROPEA

Part 3: Type test methods

Pagina I


PREMESSA NAZIONALE La presente norma costituisce il recepimento, in lingua inglese, della norma europea EN 14175-3 (edizione dicembre 2003), che assume così lo status di norma nazionale italiana. L’UNICHIM, ente federato all’UNI, segue i lavori europei sull’argomento per delega della Commissione Centrale Tecnica. Le norme UNI sono revisionate, quando necessario, con la pubblicazione di nuove edizioni o di aggiornamenti. È importante pertanto che gli utilizzatori delle stesse si accertino di essere in possesso dell’ultima edizione e degli eventuali aggiornamenti. Si invitano inoltre gli utilizzatori a verificare l’esistenza di norme UNI corrispondenti alle norme EN o ISO ove citate nei riferimenti normativi.

Le norme UNI sono elaborate cercando di tenere conto dei punti di vista di tutte le parti interessate e di conciliare ogni aspetto conflittuale, per rappresentare il reale stato dell’arte della materia ed il necessario grado di consenso. Chiunque ritenesse, a seguito dell’applicazione di questa norma, di poter fornire suggerimenti per un suo miglioramento o per un suo adeguamento ad uno stato dell’arte in evoluzione è pregato di inviare i propri contributi all’UNI, Ente Nazionale Italiano di Unificazione, che li terrà in considerazione, per l’eventuale revisione della norma stessa.

UNI EN 14175-3:2004

© UNI

Pagina II


EUROPEAN STANDARD

EN 14175-3

NORME EUROPÉENNE EUROPÄISCHE NORM

December 2003

ICS 71.040.10

English version

Fume cupboards - Part 3: Type test methods Sorbonnes - Parite 3: Méthodes d'essai de type

Abzüge - Teil 3: Baumusterprüfverfahren

This European Standard was approved by CEN on 1 October 2003. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: rue de Stassart, 36

© 2003 CEN

All rights of exploitation in any form and by any means reserved worldwide for CEN national Members.

B-1050 Brussels

Ref. No. EN 14175-3:2003 E


EN 14175-3:2003 (E)

Contents page Foreword......................................................................................................................................................................3 Introduction .................................................................................................................................................................4 1

Scope ..............................................................................................................................................................5

2

Normative references ....................................................................................................................................5

3 3.1 3.2 3.3

Terms and definitions....................................................................................................................................5 plane of sash ..................................................................................................................................................5 inner measurement plane .............................................................................................................................5 containment factor (CF) .................................................................................................................................6

4 4.1 4.2 4.3 4.4

Test room and general test conditions........................................................................................................6 Dimensions and construction ......................................................................................................................6 Test room conditions ....................................................................................................................................6 Fume cupboard installation ..........................................................................................................................6 Test conditions ..............................................................................................................................................6

5 5.1 5.2 5.3 5.4 5.5 5.6

Air flow tests...................................................................................................................................................7 Extract volume flow rate ...............................................................................................................................7 Face velocity...................................................................................................................................................7 Containment ...................................................................................................................................................8 Robustness of containment........................................................................................................................14 Air exchange efficiency...............................................................................................................................15 Pressure drop...............................................................................................................................................17

6 6.1 6.2 6.3 6.4

Sash tests .....................................................................................................................................................17 Sash suspension test ..................................................................................................................................17 Sash displacement test ...............................................................................................................................18 Protection against splashes .......................................................................................................................18 Sash stop and alarm test ............................................................................................................................18

7

Air flow indicator tests ................................................................................................................................18

8

Construction and materials tests ...............................................................................................................18

9

Illuminance test ............................................................................................................................................18

10

Test report ....................................................................................................................................................18

Annex A (informative) Sound tests..........................................................................................................................20 Bibliography ..............................................................................................................................................................21

2


EN 14175-3:2003 (E)

Foreword This document (EN 14175-3:2003) has been prepared by Technical Committee CEN/TC 332 “Laboratory equipment”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 2004, and conflicting national standards shall be withdrawn at the latest by June 2004. Annex A is informative. This European Standard EN 14175 consists of the following parts, under the general title Fume cupboards; ⎯

Part 1: Vocabulary

⎯

Part 2: Safety and performance requirements

⎯

Part 3: Type test methods

⎯

Part 4: On-site test methods

⎯

Part 5: Recommendations for installation and maintenance (in preparation)

⎯

Part 6: Variable air volume fume cupboards (in preparation)

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom.

3


EN 14175-3:2003 (E)

Introduction The objective of this European Standard is to specify type test methods relevant to the assessment of the safety and performance of fume cupboards.

4


EN 14175-3:2003 (E)

1

Scope

This part of the European Standard EN 14175 specifies type test methods for the assessment of safety and performance of fume cupboards. Relevant requirements are specified in Part 2 of this European Standard. For terms and their definitions EN 14175-1 applies. For safety and performance requirements of fume cupboards EN 14175-2 applies. NOTE

For on-site test methods of fume cupboards, Part 4 of this European Standard is in preparation.

For the testing of microbiological safety cabinets EN 12469 applies.

2

Normative references

This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN 12665, Light and lighting — Basic terms and criteria for specifying lighting requirements. EN 13150:2001, Workbenches for laboratories — Dimensions, safety requirements and test methods. EN 14175-1:2003, Fume cupboards — Part 1: Vocabulary. EN 14175-2:2003, Fume cupboards — Part 2: Safety and performance requirements. EN ISO 5167-1, Measurement of fluid flow by means of pressure differential devices inserted in circular crosssection conduits running full — Part 1: General principles and requirements (ISO 5167-1:2003). EN ISO 12569, Thermal insulation in buildings — Determination of air change in buildings — Tracer gas dilution method (ISO 12569:2000).

3

Terms and definitions

For the purposes of this European Standard, the definitions given in EN 14175-1:2003 and the following apply.

3.1 plane of sash plane in the middle between the innermost and the outermost screen surfaces of that part of the sash forming the upper boundary of the test sash opening. NOTE

This definition replaces the definition given in EN 14175-1:2003, 5.4.

3.2 inner measurement plane plane of sash at the type test opening, except where the plane of sash does not meet the work surface of the fume cupboard. In the latter case, it is usually a non-vertical plane bounded; ⎯

at the top by the lowest point of the upper edge of the type test opening in the plane of the sash;

⎯

at the bottom by the uppermost point of the lower edge of the opening closest to the plane of sash; 5


EN 14175-3:2003 (E)

⎯

at the sides by the side edges of the opening.

NOTE 1

See examples in Figures 1 and 2.

NOTE 2

This definition replaces the definition given in EN 14175-1:2003, 7.7.

3.3 containment factor (CF) ratio of calculated concentration of tracer gas in the work space of the fume cupboard to the measured concentration in the inner or outer measurement plane. NOTE The containment factor is no constant value but depends on the extract volume flow rate and the measured concentration of tracer gas.

4

Test room and general test conditions

4.1

Dimensions and construction

The test room shall consist of an enclosure of cuboid shape, constructed of suitable materials, within an existing building or laboratory. The internal width and length shall be not less than 4,0 m and the ceiling height not less than 2,7 m. The ceiling and floor shall be level and the room shall be devoid of internal supports, internal walls or other obstacles to the airflow.

4.2

Test room conditions

The room air temperature shall be (23 ± 3) °C. The make-up air temperature during measurements shall be room air temperature ± 1 °C. Temperature gradients shall be avoided to the greatest possible extent. The make-up air shall be supplied at a distance greater than 2 m from the front of the fume cupboard. The test zone boundary shall extend approx. 1,5 m in front of the fume cupboard and approx. 1,0 m from the outer sidewalls of the cupboard over the full room height. Room extract air shall be extracted symmetrically on the opposite side to the make-up air supply and from outside the test zone. The air speed shall be less than 0,1 m/s at the test zone boundaries. Care shall be taken regarding uncontrolled air streams and draughts entering into the test room. Any device the temperature of which exceeds 40 °C, except components which form part of the fume cupboard and/or the test equipment, shall be located outside the test zone boundaries. The air extracted from the test room shall be discharged to atmosphere in such a way as to prevent its reentrainment in the make-up air.

4.3

Fume cupboard installation

The fume cupboard shall be installed centrally on a wall with its back to the wall. The test shall be carried out on the fume cupboard installed in the test room in accordance with the manufacturer's installation instructions.

4.4 4.4.1

Test conditions General

No person other than the operator(s) shall be present in the test room during the measurements. No person shall remain in the test zone during the measurements.

6


EN 14175-3:2003 (E)

There shall be no unnecessary obstructions or equipment within the test zone. No equipment other than that necessary for the tests shall be in the fume cupboard. Windows and doors of the test room shall remain closed during measurements. NOTE

Observance of all test conditions is crucial for reproducibility and comparability of the test results.

4.4.2

Test sash positions

4.4.2.1

Vertical sash fume cupboards

The sash shall be set to the height of 500 mm ± 1 % measured in the center of the opening. If the maximum height is less than 500 mm, the maximum operational sash opening shall be used and noted. If any additional opening is used, this shall be noted in the test report. 4.4.2.2

Horizontal sash fume cupboards

Sash(es) shall be set at one side opening of 500 mm ± 1 %. If the maximum sash opening is less than 500 mm, then the maximum opening shall be used and noted. The test shall be carried out with the first side opening and shall be repeated with the opening at the other side. If any additional opening is used, this shall be noted in the test report. 4.4.2.3

Combination sash(es)

Vertical sash test: all horizontal sash(es) shall be set to the minimum sash opening and the procedure as in 4.4.2.1 shall be followed. Horizontal sash test: vertical sash(es) shall be set to the minimum sash opening and the procedure as in 4.4.2.2 shall be followed. If any additional opening is used, this shall be noted in the test report. 4.4.3

General procedure

The type testing procedures shall be applied to one example of a production model of the fume cupboard to be tested. Adjust the make-up air and extract air systems to give the required flow rates and test conditions. Switch on all instruments and data recording (storing) device(s), and allow sufficient time for the instruments to stabilise.

5

Air flow tests

5.1

Extract volume flow rate

For each extract volume flow rate setting, the flow rate shall be measured in the extract duct in accordance with EN ISO 5167-1. The uncertainty of measurement shall not exceed ± 5 %.

5.2

Face velocity

5.2.1 5.2.1.1

Test equipment Anemometer

The anemometer shall be of the unidirectional type with a directional sensitivity of ± 20°. The time constant of the anemometer shall be less than 0,5 s. The uncertainty of an individual measurement shall not exceed 0,02 m/s + 5 % of the reading in the range of 0,2 m/s to 1,0 m/s. An anemometer with a valid calibration certificate shall be used. 7


EN 14175-3:2003 (E)

5.2.1.2

Data recording

A means of recording the output of the anemometer for subsequent analysis shall be provided. 5.2.2

Probe positions

The anemometer probe shall be positioned at points formed by the intersection of lines on the inner measurement plane (see examples in Figure 1) as follows: a)

a series of at least three equally spaced lines between the side boundaries of the inner measurement plane with the two outermost lines (100 ± 5) mm from the side boundaries. The lines in between shall be at a distance of 400 mm or less from the outermost lines and to each other.

b)

a series of at least three equally spaced lines between the horizontal boundaries of the inner measurement plane with the two outermost lines (100 ± 5) mm from the horizontal boundaries. The lines in between shall be at a distance of 400 mm or less from the outermost lines and to each other.

5.2.3

Test procedure

Measurements shall be made with the anemometer probe located at each of the measurement grid points. Adjust the orientation of the sensor so that its measurement direction is perpendicular to the inner measurement plane. Disturbances to the space upstream of the sensor shall be minimised. Measure and record the individual velocity component vi perpendicular to the inner measurement plane at regular intervals of 1,0 s or less for a period of at least 60 s. 5.2.4

Data analysis and results

Calculate at each measurement point by equation (1) the mean value

v of the measured velocity components vi in

meter per seconds and round the result to the second decimal place:

1 n

v=

n

∑

vi

(1)

i =1

where n is the number of measurements taken during the period of min. 60 s. Calculate at each measurement point by equation (2) the standard deviation components

s r of the measured velocity

vi in meter per seconds and round the result to the second decimal place:

∑ (v n

sr =

i

−v

i =1

n −1

)

2

(2)

Calculate the spatial average velocity (see EN 14175-1:2003, 7.6) in meters per seconds at the type test opening and round the result to the second decimal place.

5.3

Containment

5.3.1 5.3.1.1

Test equipment General

The following test equipment shall be used. Other equipment and/or test gas may also be used provided that it is proven to give the same results within ± 10 %. Materials of construction should not effect the test results. All instruments shall have a valid calibration. 8


EN 14175-3:2003 (E)

5.3.1.2

Tracer gas

The tracer gas shall be sulphur hexafluoride (SF6). 5.3.1.3

Test gas

The test gas shall be (10 ± 1) % volume fraction of sulphur hexafluoride (SF6) in nitrogen (N2). The storage temperature of the test gas shall be at the test room temperature ± 2 °C. 5.3.1.4

Test gas flow regulator

The test gas flow regulator shall be capable of regulating the flow rate with a maximum permissible error of ± 5 %. 5.3.1.5

Test gas injector

The test gas injector shall be a hollow cylinder made of sintered metal with a length between 20 mm and 25 mm and a diameter between 10 mm and 15 mm. The pressure drop through each test gas injector shall be within 10 % of their mean value. Test gas injectors shall be connected to the test gas source by flexible tubes of equal length. 5.3.1.6

Sampling probe

Each sampling probe shall consist of a tube of internal diameter (10 ± 1) mm and a length of at least 100 mm. The tube's wall thickness shall not exceed 2 mm. 5.3.1.7

Sampling manifold

The sampling manifold shall be a hollow cylinder with a minimum aspect ratio (diameter/height) of 10. The sampling probe connecting tubes shall be evenly distributed around the perimeter of the cylinder with the manifold outlet in the centre. 5.3.1.8

Connecting tubing

The sampling probes shall be connected to the sampling manifold by flexible tubes of equal lengths. 5.3.1.9

Sampling pump

The sampling pump shall be capable of operating at a flow rate constant within ± 5 %. 5.3.1.10

Gas analyser -8

The gas analyser including the connected means of recording shall have a detection level of 10 or less volume fraction of the tracer gas. 5.3.1.11

Time constant of the test system

The time constant of the sampling system including gas analyser shall be less than 15 s. 5.3.1.12

Data recording

A means of recording the output signal of the gas analyser for subsequent analysis shall be provided. The recording interval shall be 2 s or less. 5.3.2

Test conditions -8

The background concentration of tracer gas in the test room shall not exceed 10 volume fraction.

9


EN 14175-3:2003 (E)

5.3.3

Positioning of test equipment for inner measurement plane

Nine sampling probes (see 5.3.1.6) shall be arranged in a grid formed by the intersection of lines as follows: a)

three equally spaced lines in the vertical direction. The space between the lines shall be (100 + 5) mm.

b)

three equally spaced lines in the horizontal direction. The space between the lines shall be (100 + 5) mm.

The test gas injector (see 5.3.1.5) shall be arranged with its centre in-line and (150 + 5) mm from the centre of the sampling probe grid. The sampling probe grid shall be positioned together with the injector so that the sampling probes are on the inner measurement plane and the injector is in the workspace of the fume cupboard on a plane (150 + 5) mm from the inner measurement plane. Figure 1 and Figure 2 show examples of the positioning of the inner measurement plane for different designs of fume cupboards.

Key 1 2

inner measurement plane test sash opening

Figure 1 — Inner measurement plane

10


EN 14175-3:2003 (E)

Key

1 2 3 4 5

sash plane horizontal sashes sash frame handle or airfoil upper reference point

6 7 8 9 10

inner measurement lower reference point airfoil work surface test sash opening

Figure 2 — Example for exact positioning The sampling probe grid shall be positioned on the inner measurement plane with its centre probe at points formed by the intersection of lines as follows: c)

a series of equally spaced lines between the vertical side boundaries of the inner measurement plane with the two outermost lines (130 + 5) mm from the vertical side boundaries. Any lines in between shall be at a distance of 600 mm or less from the outermost lines and to each other.

d)

a series of equally spaced lines between the horizontal boundaries of the inner measurement plane with the two outermost lines (130 + 5) mm from the horizontal boundaries. Any lines in between shall be at a distance of 600 mm or less from the outermost lines and to each other.

5.3.4 5.3.4.1

Positioning of test equipment for outer measurement plane Injector grid

Nine test gas injectors shall be arranged inside the workspace of the fume cupboard on a plane (200 + 5) mm away from the plane of sash. They shall be positioned with horizontal axis, the test gas flow direction towards the sash and in a grid formed by the intersection of the following lines: a)

three equally spaced vertical lines between the two extreme side boundaries of the sash opening with the two outermost lines (100 + 5) mm from the two extreme side boundaries.

b)

three horizontal lines with the bottom line (100 + 5) mm, the middle line (250 + 5) mm and the top line (650 + 5) mm above the bottom horizontal boundary of the sash opening. 11


EN 14175-3:2003 (E)

5.3.4.2

Sampling probe grid

The sampling probes (see 5.3.1.6) shall be positioned at grid points formed by the intersection of lines on the outer measurement plane as follows: a)

a series of equally spaced vertical lines between the side boundaries of the outer measurement plane with the two outermost lines on the side boundaries. Any lines inbetween shall be at a distance of 400 mm or less from the outermost lines and from each other.

b)

a series of horizontal lines between the horizontal boundaries of the outer measurement plane with the two outermost lines on the horizontal boundaries and the penultimate lines (200 + 5) mm from the horizontal boundaries. Any lines in between shall be equally spaced at a distance of 200 mm or less for vertical sashes respectively 400 mm or less for horizontal sashes from the penultimate lines and from each other.

Figure 3 shows examples of the positioning of the outer measurement plane for four different designs of fume cupboards.

Key 1 2

outer measurement plane test sash opening

Figure 3 — Outer measurement plane Where the plane of the sash does not meet the work surface, the lowest row of sampling probes shall be positioned (50 ± 5) mm in front of the vertical plane through the front edge of the work surface. If the handle of the sash is such that it prevents the movement of the sash with the sampling probes in this position, the sampling probes shall be placed further away but as close as possible to the outer measurement plane. The position of each sampling probe shall be recorded in the test report. When low level fume cupboards or walk-in fume cupboards are tested, the test report shall record the height of positioning of the injector grid and the sample grid. When the test opening exceeds 1000 mm, the distance between horizontal lines [see b)] may be 400 mm instead of 200 mm. 5.3.5 5.3.5.1

Test procedure Preparation

Switch on all supply and extract air systems and adjust controls to give specified flow rates. Connect the cylinder of test gas to the test gas flow regulator and to the test gas injector(s). Connect the sampling probes to the collecting and analysing system. Switch on suction pumps, the gas analyser and the data recording/storage system and allow ample time for the instruments to stabilise. 12


EN 14175-3:2003 (E)

5.3.5.2

Inner measurement plane test procedure

Set the sash to the test sash opening. Position the sampling probe grid at one of the test positions. Turn on the test gas, adjust the flow rate to 2,0 l/min and allow it to stabilise. Measure and record the tracer gas (SF6) concentration for 360 s. Stop the injection of the test gas and analyse the data according to 5.3.6.1. Repeat the test at the same test position for two further times if the mean tracer gas (SF6) concentration exceeds a -8 volume fraction of 10 during the test period described in 5.3.6.1. Repeat the test procedure above for other test positions at the same test opening. Repeat the test procedure above for other test sash openings according to 4.4.2. 5.3.5.3

Outer measurement plane test procedure

Set the sash to the test sash opening. Turn on the test gas, adjust the flow rate to 4,5 l/min and allow it to stabilise. Measure and record the tracer gas (SF6) concentration for 780 s. After a period of 360 s close the sash to its minimum opening in (1

± 0,2) s.

After a further period of 240 s open the sash to the test sash opening in (1

± 0,2) s.

After a further period of 180 s, stop the injection of the test gas and analyse the data according to 5.3.6.2. -8

Repeat the test for further two times if the mean tracer gas (SF6) concentration exceeds a volume fraction of 10 for any of the test periods described in 5.3.6.2. Repeat the test procedure above for other test sash openings according to 4.4.2. 5.3.6 5.3.6.1

Data analysis and results Inner measurement plane data analyses and results

For each test position and test opening analyse the data as follows: Discard the data for the initial period of 59 s. Calculate the mean tracer gas (SF6) concentration 1 as volume fraction for the test period from 60 s to 360 s and round the result to the second decimal place. Calculate optionally the dimensionless inner measurement Containment Factor CF1 as follows:

CF1 = q (Q × ϕ1 )

(3)

where q is the flow rate of tracer gas (SF6) and Q is the fume cupboard extract flow rate. Round the CF1 value to the nearest integer and indicate if the result is limited by the detection limit of the instrument.

13


EN 14175-3:2003 (E)

5.3.6.2

Outer measurement plane data analyses and results

For each test opening analyse the data as follows: a)

Discard the data for the initial period of 59 s.

b)

Calculate the mean tracer gas (SF6) concentration 2 as volume fraction for the test period from 60 s to 360 s and round the result to the second decimal place. Calculate optionally the dimensionless outer measurement Containment Factor CF2 as follows:

CF 2 = q (Q × ϕ 2 )

(4)

Round the CF2 value to the nearest integer and indicate if the result is limited by the detection limit of the instrument. c)

Calculate the mean tracer gas (SF6) concentration 3 as volume fraction for the test period from 361 s to 420 s and round the result to the second decimal place. Calculate optionally the dimensionless outer measurement Containment Factor CF3 as follows:

C F 3 = q (Q × ϕ 3 )

(5)

Round the CF3 value to the nearest integer and indicate if the result is limited by the detection limit of the instrument. d)

Calculate the mean tracer gas (SF6) concentration 4 as volume fraction for the test period from 421 s to 600 s and round the result to the second decimal place. Calculate follows:

optionally

the

dimensionless

outer

measurement

Containment

Factor

C F 4 = q (Q × ϕ 4 )

C F4

as

(6)

Round the CF4 value to the nearest integer and indicate if the result is limited by the detection limit of the instrument. e)

Calculate the mean tracer gas (SF6) concentration 5 as volume fraction for the test period from 601 s to 780 s and round the result to the second decimal place. Calculate follows:

optionally

the

dimensionless

outer

measurement

CF 5 = q /(Q × ϕ5 )

Containment

Factor

C F5

as

(7)

Round the CF5 value to the nearest integer and indicate if the result is limited by the detection limit of the instrument.

5.4 5.4.1

Robustness of containment Test equipment

The test equipment and its arrangement shall be as described in 5.3.

14


EN 14175-3:2003 (E)

In addition a flat rectangular plate with height of (1,90 ± 0,01) m, width of (0,40 ± 0,01) m and thickness of (20 ± 5) mm shall be mounted in front of the fume cupboard. The plate shall be movable during the robustness of containment test with a speed of (1,0 ± 0,1) m/s across the front of the fume cupboard. 5.4.2

Test conditions

The test conditions shall be as in 5.3.2. 5.4.3

Positioning of test equipment

The test gas injectors and the sampling probes shall be positioned as in 5.3.4. The flat rectangular plate shall be mounted upright and perpendicular to the plane of sash (200 + 5) mm above the floor, (400 + 5) mm from the farthest part of the plane of sash. In case of inclined plane of sashes the outermost point of the plane of sash shall be taken as reference for the distance. 5.4.4

Test procedure

Set the sash to the test sash opening. The plate standing upright and perpendicular to the plane of sash shall be moved backward and forward across the face of the fume cupboard. The traverse of the plate shall extend for min. 600 mm on each side beyond the width of the fume cupboard. The time between each traverse shall be (30 + 2) s. Start the test procedure as in 5.4. Measure and record the tracer gas concentration. After 60 s, start the plate moving across the face of the fume cupboard for six complete traverses. Continue recording the gas analyser signal for a further 30 s. Stop the test gas injection and analyse the data in accordance with 5.4.5. Repeat the test procedure for other test sash openings. 5.4.5


For each test sash opening analyse the data as follows: Discard the data for the initial period of 59 s. Calculate the mean tracer gas (SF6) concentration R as volume fraction for the test period from 60 to 240 s and round the result to the second decimal place. Calculate optionally the dimensionless Robustness Containment Factor CFR as follows:

CFR = q /(Q × ϕ R )

(8)

where Q is the fume cupboard extract flow rate and q is the flow rate of tracer gas (SF6). Round CFR to the nearest integer and indicate if the result is limited by the detection limit of the instrument.

5.5

Air exchange efficiency

5.5.1 5.5.1.1

Test equipment Test gas

The test gas shall be as in 5.3.1.3. 5.5.1.2

Test gas flow regulator

The test gas flow regulator shall be as in 5.3.1.4. 15


EN 14175-3:2003 (E)

5.5.1.3

Test gas flow rate

The test gas flow rate shall be such that the steady state volume fraction of tracer gas at the point of connection to -6 -6 the extract system shall be in the range 5 x 10 to 8 x 10 . 5.5.1.4

Test gas injector

The test gas injector shall be as in 5.3.1.5. 5.5.1.5

Sampling probe

The sampling probe shall consist of a tube of (10 5.5.1.6

± 1,0) mm internal diameter

Connecting tubing

The sample probe shall be connected to the gas analyser (see 5.3.1.10) by flexible tubing. 5.5.1.7

Time constant

The time constant of the test system shall be less than or equal to one half of the decay time. 5.5.1.8

Data recording

A means of recording the output signal of the gas analyser shall be provided. The recording interval shall be 0,5 s or less. 5.5.2

Positioning of injector grid and sampling probe

The injector grid shall be as in 5.3.4.1. The positioning of the sampling probe shall be within a straight length (at least 10 times the duct diameter) of extract ductwork and be located 6 diameters downstream of the beginning of the extract ductwork and at the centre of its cross-section. 5.5.3 5.5.3.1

Procedure Preparation

Switch on all the supply and extract air systems and adjust the controls to give specified flow rates and conditions. Connect the cylinder of test gas to the test gas injectors. Connect the sampling probe to the gas analyser. Connect the sample outlet of the gas analyser to the fume cupboard extract duct and downstream of the sampling point. Switch on the sampling pump, the gas analyser and the data recording device, and allow sufficient time for the instruments to stabilise. 5.5.3.2

Test procedure

Close the fume cupboard sash(es) to its minimum sash opening. Turn on the tracer gas (SF6), switch on the test gas flow regulator and adjust the flow rate to result in the required tracer gas concentration in the duct. Measure and record the tracer gas (SF6) concentration. After 200 s stop the test gas. The tracer gas (SF6) concentration should now start to decay. Carry on with the measurement and recording of the tracer gas (SF6) concentration for a further period of at least 200 s.

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EN 14175-3:2003 (E)

5.5.4


Calculate the air change rate per hour, n, according to EN ISO 12569 from the gradient of a log-linear fit using the measured values from 5.5.3.2 in the range of 80 % to 20 % of the initial tracer gas concentration. Calculate the air exchange efficiency in percent as quotient of measured and theoretical air exchange rate, rounding the result to the first decimal place, with equation (9):

ε =

100 n 100 n Vfc = Q / Vfc Q

(9)

where Q is the extract volume flow rate and Vfc is the internal volume of the fume cupboard's workspace.

5.6

Pressure drop

5.6.1

General

The pressure difference measured according to this clause is called pressure drop of the fume cupboard and shall be indicated in the manufacturer's manual together with the corresponding airflow rate. The test room and the general test conditions shall be as in clause 4. 5.6.2

Test equipment

A device capable of measuring air pressure differences with an uncertainty of measurement not exceeding of the reading. 5.6.3

± 10 %

Test sash positions

Tests shall be carried out with fume cupboard sash(es) at the type test sash position(s) (see 4.4.2). 5.6.4

Positioning of pressure taps

At the point of connection to the extract system, fit a minimum of four pressure taps evenly distributed around the circumference of the connecting extract duct. Interconnect all pressure taps to have one common outlet for the measurement of the average pressure compared to the air pressure in the room. 5.6.5

Test procedure

Allow the flow to stabilise and measure the average pressure drop for min. 60 s under the conditions detailed in 5.6.3. If the cupboard is equipped with an in-built pressure tap, the pressure shall be measured at this point also. 5.6.6

Expression of results

Express the measured pressure drop in Pascal. Record the cross sectional area of the connecting duct where the pressure drop was measured.

6 6.1

Sash tests Sash suspension test

Set the sash to the test sash position. Disconnect one of the suspension devices of the sash. The sash shall remain in the vicinity of its initial position. Repeat the test with the other suspension devices.

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EN 14175-3:2003 (E)

6.2

Sash displacement test

Measure the sash displacement force at three positions equidistant along the sash edge(s) for any possible direction of movement.

6.3

Protection against splashes

A visual inspection shall be performed whether protection against splashes in accordance with EN 14175-2:2003, 7.3.5, is given.

6.4

Sash stop and alarm test

The sash stop shall be inspected and functionally tested in respect of the marking on the fume cupboard (see EN 14175-2:2003, 7.3.1) and its operation in accordance with EN 14175-2:2003, 7.3.2. The audible and visual sash alarm, if provided in accordance with EN 14175-2:2003, 7.3.2, shall be tested by inspection during an appropriate operation of the sash.

7

Air flow indicator tests

If the fume cupboard under type test is provided with an incorporated air flow indicator, the function of the air flow indicator shall be tested to comply with the requirements specified in EN 14175-2:2003, 8.2. The following items shall be tested during appropriate operation: a)

alarm when manufacturer specified or type test established extract volume flow rates are failed;

b)

noticeability of the visual alarm and silencing of the audible alarm, if provided.

The following items shall be reported after inspection: c) fault of power supply; d) non-availability of the air flow indicator in case of contamination at sensor or electronic failure and/or disconnection which may be simulated by appropriate means.

8

Construction and materials tests

Testing of the basic safety requirements specified in EN 14175-2:2003, 7.1 and 7.2 shall be performed by visual inspection, function testing and dimensional checking aided by simple measurement equipment such as a tape measure. If there is a need of measurement and evaluation of deformation (see EN 14175-2:2003, 7.2.2 and 7.2.6), this can be performed in accordance with EN 13150:2001, 6.2 and A.3.4. The use of the requested materials in accordance with EN 14175-2:2003, clause 6, may be proven by manufacturer's declaration or by certificate.

9

Illuminance test

Illuminance shall be measured in min. 8 points per square meter of the work surface, homogeneously distributed. Calculate the mean value and the uniformity (terms according to EN 12665). The Ra-Index shall be stated by the manufacturer and reported.

10 Test report The type test report shall include the following: 18


EN 14175-3:2003 (E)

a)

name (or trade mark) and the address of the manufacturer;

b)

make or model of the fume cupboard;

c)

description of the fume cupboard including the external and internal dimensions, fitting, services, outlet controls, taps, sinks etc.;

d)

name and address of the party which carries out the tests;

e)

date of the test, signature and name of the testing person;

f)

description of the instrumentation, including its specification and calibration, and the test procedure used;

g)

description of the test room and the test conditions maintained during the tests, including air temperature and relative humidity;

h)

sash opening employed in the tests;

i)

extract volume flow rate(s);

j)

results of the face velocity test;

k)

results of the containment tests in terms of tracer gas concentration(s) i as function of the tested extract volume flow rate Q and optionally, if calculated, the Containment Factor(s) CFi (see 5.3.6);

l)

results of the robustness tests in terms of tracer gas concentration FR and optionally, if calculated, the Robustness Containment Factor CFR (see 5.4.5);

m) result of the air exchange efficiency test; n)

pressure drop of the fume cupboard and the dimensions of the extract duct, such as diameter, where the pressure drop is measured;

o)

sash suspension observation;

p)

sash displacement force at each measurement point;

q)

protection against splashes observation;

r)

sound power level and emission sound pressure level (if measured);

s)

results of the illuminance test;

t)

description of the air flow indicator if installed at the time of the type test;

u)

reference to this European Standard EN 14175-3 and, if appropriate, any deviation.

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EN 14175-3:2003 (E)

Annex A (informative) Sound tests

If sound power levels are stated, they shall be measured in accordance with the guidelines for the use of basic standards given in EN ISO 3740. If emission sound pressure levels are stated, they shall be measured in accordance with EN ISO 11204.

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EN 14175-3:2003 (E)

Bibliography

EN 12469, Biotechnology — Performance criteria for microbiological safety cabinets. EN ISO 3740, Acoustics — Determination of sound power levels of noise sources — Guidelines for the use of basic standards (ISO 3740:2000). EN ISO 11204, Acoustics — Noise emitted by machinery and equipment — Measurement of emission sound pressure levels at a work station and at other specified positions — Method requiring environmental corrections (ISO 11204:1995).

21


UNI Ente Nazionale Italiano di Unificazione Via Battistotti Sassi, 11B 20133 Milano, Italia

La pubblicazione della presente norma avviene con la partecipazione volontaria dei Soci, dell’Industria e dei Ministeri. Riproduzione vietata - Legge 22 aprile 1941 Nº 633 e successivi aggiornamenti.

14175-3

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