High Pressure Water Jetting

Procedure

High Pressure Water Jetting Mar 2009

OS.SICES.High Pressure Water Jetting

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This Document is Uncontrolled in Hard Copy Format Copyright and intellectual property rights embodied in this document remain vested in Contract Resources Pty Ltd (ABN 63113182504). Except as provided by the Copyright Act 1968, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means without the prior written permission of Contract Resources Pty Ltd.

Contract Resources Group


Contents 1

SCOPE .............................................................................................................................4

2

OBJECTIVE .....................................................................................................................4

3

DEFINITIONS ...................................................................................................................4

4

RISK CONTROL APPROACH TO HYDRO JETTING ......................................................6

5

PERSONNEL TRAINING REQUIREMENTS ....................................................................7 5.1

BASIC INTRODUCTION LEVEL.................................................................................................... 7

5.2

INTERMEDIATE LEVEL .............................................................................................................. 8

5.3

SUPERVISOR/ ASSESSOR LEVEL .............................................................................................. 8

6

PERSONAL PROTECTIVE EQUIPMENT ........................................................................8

7

GENERAL CONSIDERATIONS .......................................................................................9 7.1

HOUSEKEEPING .................................................................................................................... 12

7.2

W ORKING SURFACES ............................................................................................................ 12

8

EQUIPMENT AREA PREPARATION .............................................................................12 8.1

GENERAL PREPARATIONS ...................................................................................................... 12

8.2

W ORK LOCATION PREPARATIONS ........................................................................................... 13

8.3

W ATER SUPPLY ................................................................................................................... 13

8.4

PERMIT REQUIREMENTS ........................................................................................................ 13

8.5

ENVIRONMENTAL CONSIDERATIONS ........................................................................................ 13

9

TOOL AND MACHINE REQUIREMENTS ......................................................................13

10

WORK PRACTICES .......................................................................................................14

11

MANUAL TUBE FLEXI-LANCING .................................................................................15

11.1

USE OF MINI MOLES (BOILER SNAKES) .................................................................................. 15

11.2

GENERAL REQUIREMENTS ..................................................................................................... 16

11.3

DO’S AND DON’TS OF MANUAL TUBE FLEX LANCING ................................................................ 17

12

HPWJ GUN JETTING ....................................................................................................18

12.1

GENERAL REQUIREMENTS ..................................................................................................... 18

12.2

DO’S AND DON’TS OF SAFE GUN JETTING ............................................................................... 19

13

RIGID LANCING ............................................................................................................20

13.1

DO’S AND DON’TS OF RIGID LANCING ..................................................................................... 21

14

APPENDIX 1 CHECKLIST TO START AND OPERATE HPWJ .....................................22

15

RESPONSIBILITIES .......................................................................................................23

16

ASSOCIATED DOCUMENTS.........................................................................................23

17

REFERENCES ...............................................................................................................23

18

ENVIRONMENTAL IMPACTS AND ASPECTS STATEMENT .......................................23

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Date Last Modified 22/11/2010 3:44 PM

Author Mike Fitzpatrick

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COMPETENCY ASSESSMENT .............................................................................................24 AUDIT.....................................................................................................................................26 AUDIT.....................................................................................................................................27 AUDIT.....................................................................................................................................28

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1


Scope This procedure has been developed to address the features of high pressure water jetting (HPWJ) equipment and define the minimum requirements for its safe operations and use.

2

Objective This procedure has been developed to address the inherent risks of hydrojetting and to provide minimum requirements for the safe operations of hydrojetting or water jet cleaning equipment. All high pressure water jetting equipment and actions will comply with – Australian/New Zealand Standard AS/NZS 4233.1 “High Pressure Water (Hydro) Jetting Systems; Part 1: Guidelines for Safe Operation and Maintenance Part 2: Construction and Performance.

Equipment that does not comply with AS/NZS 4233 will not be used.

3

Definitions Anti-Withdrawal - A device-prevents a nozzle from reversing direction inside a pipe and re-exiting Automatic Unloader - A device (valve) which automatically removes operating pressure on the pump by opening a free flow path for the pump output when it senses the line to the nozzle is closed. It automatically adjusts the amount of water sent to the nozzle line, dependent on the pressure set by the operator and the capacity of the pump. Burst Disc - A safety device designed to rupture and discharge the fluid so as to prevent a safe pre-determined pressure being exceeded. (Once “burst” needs to be replaced before operations continue) Class A Systems - High pressure water jetting systems are identified as Class A systems when the maximum energy produced by the system, measure in pressure volume units per minute (e.g. bar litres/minute), falls in the range 800 bar litres minute and 5600 bar litres/minute Class B Systems - High pressure water jetting systems are identified as Class B systems when the maximum energy produced by the system, measure in pressure volume units per minute (e.g. bar litres/minute), exceeds 5600 bar litres/minute Dry Shut-Off Valve - An operator's control valve which has the capability to completely shut off flow to the nozzle. Typically seen as a hand gun or a foot valve. Should only be used in conjunction with a regulator or automatic unloader valve Dump System - An operator controlled system that opens a free flow path for the water, thereby reducing the system pressure to a safe level without shutting off the flow to the nozzle

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Flex Lancing - A flexible tube used to feed a nozzle through an enclosed space such as a pipeline. The flexible lance is most commonly used where a tube contains one or more bends High Pressure Water Cleaning (HPWJ) - The use of high pressure water, with or without the addition of other chemicals or abrasives to remove matter from various surfaces High Pressure Water Jetting System - A water delivery system consisting of an energy source, pump, control mechanism, hoses, pipes and nozzles and other attachments necessary for the equipment to function as a system High Pressure Hose - Flexible hose used to transfer high pressure water from the pump to the cleaning tool being used Hose Restrainer - Hose restrainer, constructed either of nylon or braided wire that spans a hose connection. It prevents the hose from separating in an uncontrolled manner should the connection between the hoses fail Jetting Gun - A portable combination of operators control valve, lance and nozzle, resembling a gun in layout and outline Lancing - A lance and nozzle combination is inserted into, and retracted from, the interior of a pipe or tube. It may be self propelled by its backward directed jets and may be manufactured in various shapes, sizes and combinations of rotating forward and backward directed jets. Lancing is most commonly used for cleaning heat exchanger tubes Moleing - A hose fitted either with a nozzle or a nozzle is attached to a lance is inserted into, and retracted from the interior of a pipe. It is a system used to blast deposits out of the end of a pipe or commonly intended for cleaning the internal tube. Moeling is generally used with larger piprs Nozzle - A device with one or more openings orifices where the fluid discharges from the system. The nozzle restricts the area of flow of the fluid, accelerating the water to the required velocity and shaping it to the required flow pattern and distribution for a particular application. Combinations of forward and backward nozzles are often used to balance the thrust. Such nozzles are commonly referred to as tips, jets or orifices Regulator Valve - Automatically adjusts the amount of water sent to the nozzle line dependent on the pressure set by the operator and the capacity of the pump Rigid Lance - A rigid tube with a nozzle attachment that can be either hydraulically or manually driven through straight tubes. Rigid lancing is an alternative to flexible lance cleaning of tubes Restraining Clamp - A clamp used in the anti-withdrawal device Rota Fan - A trolley-mounted low-speed rotary joint that rotates a non-rotating nozzle, via the hose Safety Valve - A valve which automatically, without the assistance of any energy other than the fluid consumed, discharges a certified quantity of the fluid so as to prevent a predetermined safe pressure from being exceeded Safety Observer - Is a member of the work crew assigned the following tasks:

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o o o o

Observing the jetting operations and barricaded area; Shutting down the system in the event of an emergency or malfunction Controlling the system pressure as requested by the jet operator Controlling the access of personnel into the barricaded area

Securing Device - Immobilizes the work piece by securing it to the ground or a nonmovable base Shot Gunning - An activity where a jetting gun is used to blast deposits out of the end of a pipe or tube. The gun is commonly fitted with a shrouded nozzle which is pushed firmly against the opening of the pipe or tube while the jet is operated in short bursts Starter Bar - A rigid piece of pipe affixed to a line mole to prevent reversing of mole in the line

4

Risk Control Approach To Hydro Jetting It is recognised by Contract Resources that HPWJ is an activity with significant inherent hazards that if approached inappropriately, presents significant risk with the potential for serious injury, including fatality. As such, Contract Resources when undertaking risk assessments during planning and operational services will ensure risk is maintained to as low as reasonably practicable by adopting the principles and practices detailed in our Risk Management Procedure. Reference: HSEQ.PRO.Risk Management Key considerations for risk management:  

Where possible HPWJ will be avoided. Other methods of cleaning will be proposed to the client and if approved implemented (e.g. chemical cleaning) Where HPWJ is required, Contract Resources will use various remote controlled mechanical devices in order to separate the operator from the high pressure water hazards. For example: Task

Equipment

External bundle cleaning

Automated external bundle cleaner

Internal bundle cleaning

Use automated internal tube cleaner which may be rotating dual rigid lance or a free lance machine

Internal shell cleaning

Use of centralizer

Cleaning of large surfaces

Use of excavator with high pressure water head

Cleaning/finishing of tank floors

Use of HPW “lawnmower”

Contract Resources operators shall be instructed trained and competency assessed prior to the use of these machines and devices.

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5




On every job, a competent, trained and experienced person must be present



A lance or gun can be operated by a person trained to the introductory HPW standard as long as all HPW guidelines including back out prevention are followed



The manual use of HPWJ equipment will only be utilized as a last resort where the use of other automated or mechanical equipment cannot be employed



When manual flexi lance cleaning of exchanger tubes is required, fail safe (antiwithdrawal) devices attached to the equipment must be used to prevent the lance exiting the tube in an uncontrolled manner



Where manual flexi lancing using mini moles (boiler snake) is to be employed by Contract Resources personnel, a JSEA must be prepared and approved by the Contract Resources General Manager or their delegate prior to commencement of the job



Prior to use of equipment Contract Resources personnel must have been trained and demonstrated competency in the Contract Resources Standard Operating Instruction specific to the equipment used

Personnel Training Requirements Within Contract Resources we identify 3 levels of HPWJ operators:

5.1

Basic Introduction Level Individual is new to the industry and has no or very minimal experience with HPWJ. This operator will be involved in high pressure water jetting jobs under supervision of an experienced operator. All people involved in HPWJ operations must be at least 18 years of age, Contract Resources and site inducted and must have successfully completed the IFAP Introduction to Hydroblasting Certificate course unless: 

They are involved in a training exercise



They are only involved in operating a safety stop/device and signed off as competent against an SOI



Contract Resources HSET Coordinators have signed off on any prior/non IFAP accredited course until one can be completed

Following training, Supervisors or nominated Advanced HPWJ trained people are able to deem someone competent against an SOI.

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5.2


Intermediate Level The Operator needs to have successfully completed the IFAP intermediate high pressure water blasting course. Operators at this level are able to plan, execute and oversee a safe hydro jetting project to a pre determined quality outcome.

5.3

Supervisor/ Assessor Level Individuals at this level have extensive experience in supervising and/or assessing and through recognition of prior learning, may not be required to participate in a HPWJ training course. This operator is in charge of the job site and is responsible for the set up and barricading of the area and safe execution of the job. They are also responsible for the training/coaching of lower level operators and client liaison. Operators in this level will have completed an accredited OH&S course.

5.4

General Each person directly engaged in HPWJ will be required to have satisfactorily completed an approved HPWJ training course. In addition, personnel may also be required to be trained and certified as safe to operate associated HPWJ equipment, such as excavators and the necessary personal protective equipment use. The Contract Resources Supervisor responsible for the job must verify proof of training. Records will be maintained on the Contract Resources training register HPWJ personnel will be familiar with the requirements of these safety guidelines.

6

Personal Protective Equipment Whenever HPWJ is to be performed, a JSEA of the job must be completed and appropriate PPE must be used for job hazards identified. The risk assessment will determine if any additional or specialised personal protective equipment is necessary. Any additional precautions concerning protective equipment must be stated on the work permit.

Persons not involved in the cleaning are to be excluded from the work area. The work area will be clearly marked with warning tape and signs warning that HPWJ activities are in progress. The operator and those within the HPWJ area are required to wear as a minimum the following protective equipment when cleaning:

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Hardhat

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Safety glasses/goggles and



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7




Face shield



Hearing protection (minimum of 27bba attenuation, however consideration should be given to wearing dual hearing protection – ear plugs and ear muffs)



Heavy duty rain suit or HPWJ suit



Protective gloves (dependant on the material/substance being handles or exposed and the hazard and risk presented to the operators)



HPWJ safety rubber boots (with built in metatarsal protection) with steel caps or approved HPWJ boot over-protectors



Other equipment as required if a hazardous chemical is involved



Other PPE can be considered depending on the project and risks identified

General Considerations HPWJ or water jet cleaning equipment has varying working pressures and flow rates. The operating pressure should never exceed the rated pressure of the equipment. WARNING: When HPW Jetting using hand held equipment, a combination

of pressure and flow rate can produce significant recoil force and torque that may create an uncontrollable situation. This must be considered when documenting the JSEA and appropriate controls implemented to manage the risk to as low as reasonably practicable 

Prior to commencing any HPWJ work the operators must ensure that the following occurs: o o o



A JSEA must be prepared and authorised by the operators performing the work and the client representative The Checklist to Start and Operate High Pressure Water Equipment (appendix 1) must be completed The equipment log book must be completed

The cleaning equipment should be set-up whenever possible to have minimal impact on the surrounding site activities, out of major personnel traffic routes, and where possible a safe distance from operating equipment as determined by the operating pressure and flow rate of the HPWJ equipment Note: If possible, the HPWJ equipment and work should be located off-site and equipment to be cleaned (e.g. exchanger bundles) transported to the remote cleaning site

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If access to a cleaning area is required, the individual requiring access to the work area must obtain permission from the work Supervisor prior to entry to the area



Where an unauthorized person enters the cleaning area, the work Supervisor and/or the HPWJ operator must stop operations. Work must not resume until the area is cleared



Special HPWJ requirements that deviate from these guidelines must be covered by a JSEA developed by Contract Resources in conjunction with the client to ensure that a suitable work procedure is adopted and all safety precautions are identified. The risk control hierarchy method must be followed



Schedule the work so the number of authorized plant and other contractor personnel in the area is held to a minimum



For environmental purposes, HPWJ activities should where possible be scheduled and located such that the impact of noise associated with these activities has minimal impact on the surrounding community and site work force



The HPWJ equipment area must be barricaded using recognised barricade tape. The “exclusion zone” surrounding the operator of the high pressure jetting equipment defined by the barricade tape and warning signs must be such that a passer-by cannot come into contact with high pressure water or debris. Where barricading tape is difficult to erect (e.g. lay down areas, etc) the use of additional signage or other means of restricting access/barricading and notifying personnel of a work hazard must be considered



It may be required that the barricading and warning signs are placed at a distance greater than five (5) metres from the work zone where there is the risk that personnel may be struck by high pressure water or debris removed during the cleaning process



The Barricade tape and signs should surround hoses extending from pump equipment to cleaning area where there is risk of damage to the hoses or they present a safety risk to other site personnel. There is no restriction on the number of signs to be erected, but as good safety practice, at least two warning signs, stating “Danger, Water Blasting in Progress” must be erected around the work area



In the event it is not possible to control access to the work area or ejection of debris or water from the work area, sturdy barriers/panels must be placed/erected to shield operations



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

The pumping unit must be equipped with a safety valve and/or rupture disc capable of rapidly relieving the full capacity of the pump. The burst pressure rating of the rupture disc must comply with the requirements of AS/NZS 4233.1 (1999). The disc and or safety valve will be checked as part of the annual maintenance program on this equipment



The pumping unit should be located to minimise the length of hoses required. Considerations should be given to the distance from operating equipment. Select a location that does not require running hoses through an active access way or work area. Care must be taken to protect hoses from damage by vehicle traffic, hot lines/equipment, or external abrasion



The operating pressure of the high pressure hose and fittings must comply with AS/NZS 4233.1. Hoses should be inspected before each job and tested according to the requirements of that standard. Hoses must be identified in such a manner that the latest test date and test pressure can be determined



Hydro blasting equipment must be earthed/bonded to minimize static electricity build-up



Hose connections must have a secondary joining mechanism (e.g. hose restraint device) to prevent whipping if the connection is broken



Although no minimum length is specified within AS/NZS 4233.2 for HPWJ gun barrels, it is the Procedure of Contract Resources that the length of a HPWJ gun barrel (including nozzle) should be 48 inches (1.2 metres) and the length of entire HPWJ gun assembly should be 66 inches (1.65 metres) or as supplied by an approved manufacturer. Where the length of the barrel/gun cannot comply with these requirements, a JSEA must be prepared and approved by the Contract Resources General Manager or their delegate prior to commencement of the job



HPWJ guns must be equipped with a failsafe dead man switch. The “dead man switch” should be designed such that the operator’s hand is required to initiate high pressure water flow. Releasing the handle will immediately “dump” pressure from the gun, dump valve or the pump bypass system. Some guns are fitted with double triggers which both need to be operated to start the water flow through the barrel Note: A dump valve that will immediately dump all the water pressure when the control is released is the only approved fail-safe control



When lancing, the lance operator must only operate a foot operated fail-safe control with guard. Only the lance operator (person nearest the working end of the lance) must operate the fail-safe device WARNING - At no time should the fail-safe control be tied down or locked into position. Injury could result if the fail-safe is bypassed or locked

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7.1




Starter bars, longer in length than the diameter of the pipe will be used when line moleing. A starter rod is a rigid piece of pipe affixed to a lance or line mole to prevent reversing of lance/mole in the tube/line. The starter bar must be pressure rated to the pressure rating of the pump.



When manual line moleing/lancing operations are to be done, an "anti-withdrawal" device (back out preventor) securely fastened to the pipe MUST be installed to prevent the removal of the mole nozzle while still under pressure. No exceptions are permitted.



All operators must carry the HPWJ emergency medical alert card, provided as part of the instruction course, at all times while jetting

Housekeeping During cleaning operations, accumulations of materials may form at the pipe/tube openings. Work should be stopped and the materials removed when a safe work position or working surface cannot be maintained. This is particularly important where the work area is confined, such as platforms and scaffolds and where material debris may accumulate from the cleaning process.

7.2

Working Surfaces Blast equipment must be operated from approved work surfaces. Due to excessive back thrust exerted on the operator when using HPWJ guns, the use of ladders and "A" frames are not acceptable as work platforms.

8 8.1

Equipment Area Preparation General Preparations Warning barricade tape will be placed around the perimeter of the pump and job site. In addition to the warning tape, a warning sign indicating that “Danger - HPWJ work is in progress” or a sign with similar warning should be positioned around the work site. If the job is above ground level, warning tape and/or signs may be required below. Warning tape and/or signs will be placed along those portions of the high-pressure water hose that are outside of the barricades where there is the risk of this equipment being damaged or being a safety hazard to other site personnel. Remove warning tapes and barricades after completion of a job. When practical, items to be cleaned should be moved out of congested areas and away from people. Electrical equipment must be protected from water damage by being covered (e.g., with plastic) or shielded (e.g., by hanging a tarpaulin, etc.) and must be isolated/racked out.

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8.2


Work Location Preparations The truck/pump location should conform to operations requirements. The location should be such that the length of hoses required is minimized. Where practical avoid parking in passage or access ways. Do not operate a pumping unit inside a building or an enclosed area. Ensure that adequate working area and a surface that provides good footing is available before operations begin. Remove any hazard (e.g., oil, grease, and loose object) from working area.

8.3

Water Supply Tie-ins to the industrial water supply must be reviewed with client operations personnel. Locate the water supply hose so abrasion during operation does not wear the hose cover and cause the hose to rupture. Caution should be used when accessing fire mains water for HPWJ operations. Doing so reduces the volume of available firewater in an emergency, and there may be a potential health hazard from exposure to potentially contaminated water. It is preferable to use portable water.

8.4

Permit Requirements All work authorization must be obtained according to the permitting procedures. Where HPWJ is to take place in the immediate vicinity of electrical equipment or wiring which could result in its direct contact with the water stream (e.g., around equipment where wiring is covered with rubber, oil, insulation, etc.), the equipment is to be locked out.

8.5

Environmental Considerations Where the risk of debris/material entering the drainage systems or be an uncontrolled area, efforts must be made to block off all drains surrounding the cleaning area. Collecting and disposing of waste material must be an integral part of the project plan. Water conservation must be considered in a HPWJ project plan. Water recycling should be considered as part of this.

9

Tool And Machine Requirements Pre-start safety checks are required each day or when equipment is relocated The HPWJ equipment operators will check out the operation and condition of all critical equipment. Prior to commencing HPWJ activities the Checklist to Start and Operate High Pressure Water Equipment must be completed.

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A relief device will be installed on the high-pressure side of the pump, set to relieve at no higher than the maximum allowable working pressure of the lowest rated component in the high-pressure system. The device will be capable of limiting system pressure of the system as per the requirements of AS/NZS 4233 (1999). Prior to starting a job, the operation of the hand or foot switch should be checked while flushing the lines of any debris and before adding the correct nozzle. The switch should relieve pressure immediately without sticking. Prior to starting a job, the assembled high-pressure components will be gradually and evenly pressurized to the maximum rated capacity of the system to verify the integrity of the system and the connections. All pumps associated with high pressure water cleaning operations must have an emergency stop device. One control valve or switch will control only one high-pressure device. (One operator will operate only one high-pressure lance device, mole, or HPWJ gun at a time. All high-pressure hoses, including Safety Whips must be inspected and pressure tested as per the requirements of AS/NZS 4233 (1999). All tested hoses will be stamped by the testing provider and copies of the relevant test certificate will be retained as per the hose management procedure. Any hose used must be pressure rated to the maximum pressure output of the pump the hose is used on. All hoses, including the safety whip section of hose will be inspected for damage at the start of each job by operators responsible for the job. Hoses will have a burst pressure rating as specified by AS/NZS 4233 (1999). Hose identified as not fit for use (e.g. damaged wire braid, damaged fittings, kinked, etc) must not be used and once identified must be rendered unusable (e.g. cut fitting off, flatten fitting, remove seal cartridge, etc). High-pressure hoses for use with 1000bar equipment will have M24 fitting connections. No quick-connect fittings are to be used for this rated equipment. Quick connect/disconnect fittings are only to be used with the 20K rated equipment. The filter on the pump suction should be clean and in good operating condition. Hoses will have restrainer devices attached to prevent hose connection separation.

10

Work Practices A HPWJ crew will be composed of at least two persons. For safety reasons a crew member must be available at the pump to de-pressurise it or a remote cut off switch/device which can de-pressurise the system must be used. When undertaking the JSEA for the specific job, consideration must be made to the ergonomic factors for the operator which includes an assessment of static body position and reaction forces and the person’s fitness for the task. Work should be scheduled in such a manner to eliminate fatigue or exhaustion of personnel.

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Always be sure the pressure being used is not causing damage to the equipment being cleaned. It is recommended that only minimum pressure to do an adequate job of cleaning be used. For maximum safety, no one is to be within 7 meters in any direction of the hydro blast nozzle(s) or of an operator while HPWJ is in progress particularly when the operator is manually operating a HPWJ gun or flexi lance. Solid barricades can be used. When HPWJ equipment where the scale may release explosive vapours, or where a fine dust condition may exist, the equipment being cleaned will be grounded. At no time will the foot pedal or dump valve be locked down or jammed in the pressurized position.

11

Manual Tube Flexi-Lancing Refer to Contract Resources standard operating instructions for the specific operation of the equipment being used. Repetitive application of high pressure water to clean rows and columns of tubes or pipes. This method requires one or more persons to handle the lances and/or hoses. A safety device (back-out prevention) must be used at all times to prevent the hose assembly from being pulled out of the tube or pipe while equipment is energized or pressurized or to prevent the equipment hydraulicing back out of the tube in an uncontrolled manner.

11.1 Use Of Mini Moles (Boiler Snakes) The mini mole is a flexi lance designed for the cleaning of small diameter tubes. Due to the smaller outside diameter of the lance and nozzle and the flexibility of the lance, the mini mole is used for tubes that are too small to be cleaned using the traditional thermoplastic lances.

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The outside diameter of the mini mole lance is 0.335”/8.5mm. It can be used to clean tubes with an internal diameter as small as 0.445”/11.5mm

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The mini mole inlet fitting is 1/16” NPT



The outer layer is a double braided stainless steel wire covering



The ferrule and the nozzle are integral to the mini mole lance and cannot be removed from the lance body



The lances have a working pressure of 8,000psi/552 bar



These lances cannot be pressure tested and have a working life of 12 months (hose test certificates will define the expiry date of the lance), after twelve months the lance must be withdrawn from service and sent to Contract Resources Adelaide for disposal



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

The use of the mini mole/boiler snakes present their own unique hazards and as such the following minimum requirements must be met before a mini mole is used:



Any person using a mini mole must be trained (minimum of IFAP – “Course In Hydroblasting Induction”) and be experienced in HPWJ activities



A back out preventer must be used with the mini mole



The collets for use with the back out preventer have a gap of 7.5mm, and have 7.5 stamped on each side of the collet. These are specially machined collets for use with the mini mole. Operators of the mini mole/back out preventer must monitor the collets and the lance/ferrule/nozzle for wear as the work progresses to ensure that the mini mole ferrule will catch on the collet and not allow the ferrule to pass through the collet



A JSEA specifically formulated for the mini mole cleaning task is to be completed prior to any use of the mini mole



Before any work is undertaken with the mini mole, the General Manager of Contract Resources must be notified of the intended work and permission granted prior to the use of a Boiler Snake. The General Manger will review the JSEA to ensure it covers the relevant hazards and controls

11.2

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General Requirements 

Always assess if there is a mechanical way to do this job

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The use of rigid lance or auto free lance equipment should be considered as the first option of cleaning tubes and only when this equipment cannot be used, should manual lancing be considered as an alternative work method



High-pressure water flow to the lance will be actuated by a fail-safe, contact type switch or valve which when released, causes pressure at the lance to drop to 1bar pressure. The valve or switch must have a guard to prevent inadvertent actuation



High pressure will be applied to the nozzle only when the lance is in the tube



While moving the lance from one tube to the next, the flexi lance must not be under pressure



If the opposite end of the equipment being tube lanced is open, a cover or shield should be installed on the open end to contain the jet spray and water



Do not clean the entrance of a line with the tube lance. Clean this section of pipe with a HPWJ gun



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11.3




While tube lancing pipe openings must be properly barricaded, this should be done in addition to normal barricading preparations covered in this procedure



Do not lance tubes above shoulder level. This reduces the ability of the operator to control the flexi lance

Do’s And Don’ts Of Manual Tube Flex Lancing This method is used where space requirements prohibit the preferred option of rigid lancing or the use of the auto lance equipment. Do

Do Not

Use back out prevention (antiwithdrawal) equipment when using flexi lance equipment

Use a flex hose with frayed reinforcing braids or one that has been kinked or structurally damaged in any manner.

Shield the back of the exchanger or barricade the surrounding area to protect personnel from the spray and the potential debris exiting the tubes

Operate above the rated maximum working pressure of the hose.

Give the operator who is at the tube sheet inserting the flex lance control of the foot pedal.

Position yourself where the blast will spray on you.

Be prepared for back pressure resulting from plugged tubes.

Pull the nozzle out of a tube until the pressure is dumped.

Install a starter bar on the end of the flex hose when cleaning heat exchanger tubes and attach the selfpropelling nozzle to it. This pipe extension gives the operator better control for inserting and extracting the nozzle from the tube.

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12

HPWJ Gun Jetting

12.1

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General Requirements 

Only use AS/NZS certified HPWJ gun and attachments, as supplied by the manufacturers



The HPWJ gun operator should never point the HPWJ gun at himself or anyone else. Objects being cleaned must not be hand held



Back thrusts can be created by the high-pressure jet stream that can easily put a person off balance. Only use the minimum pressure required to perform the cleaning activity or that can be controlled comfortably by the operator



Only use AS/NZS certified nozzles and attachments



Only use attachments that are rated for use with the pump being used on the cleaning work



Watch for indications of the jets becoming plugged. This can cause unbalanced thrusts or over-pressuring of the system



Jetting with a fail-safe gun requires the operator(s) to hold the gun while directing the jet stream at the object or surface to be cleaned



The protective safety measures are mandatory to shield the operator from the high pressure jet stream



Pages 18 of 28


12.2


Do’s And Don’ts Of Safe Gun Jetting Do

Version No 1.0

Do Not

Clear the work area of light objects that could be shot by the action of the high pressure spray.

Work in areas with poor footing unless corrective measures are taken. Many surfaces become slippery when wet, so special caution should be taken to eliminate the hazard.

Be sure the nozzle is the proper size for the pressure and flow required to perform the clean activity and for the pump and equipment involved in the work.

Use unbalanced geometric patterns of jets - be sure the size and position of the jets are balanced so the thrust in opposite directions is equal.

Caution those around you of the cutting action of the jet stream.

Under any circumstances tie down the gun trigger on the gun

Be prepared for the back thrust created by the high pressure jet stream.

Forget to watch for indications that a nozzle is becoming plugged. This can cause an unbalanced thrust or a pressure overload on the system. Clean the nozzle or replace it before continuing with the cleaning operation.

Prior to jetting, test the lever on the fail-safe gun to ensure that it activates smoothly and when released, the pressure drops immediately. The lever housing should be cleaned regularly to prevent build-up of debris which might interfere with proper operation.

Use a gun barrel that is unnecessarily short. A recommended length of 48 inches (1.2 meter) is suggested for all possible operations. This helps eliminate foot and leg injuries which may result from the gun being pointed at the operator's body during jetting.



Pages 19 of 28


13

Version No 1.0


Rigid Lancing



Rigid lance equipment in operation



Operation of the machine is performed remotely



High pressure jet lances are normally fabricated from seamless austenitic stainless steel tubing with a minimum wall thickness of 0.065 in. (1.6 mm). These tubes usually have threaded fittings welded at each end which permit lances and nozzles to be changed easily



Lances for cleaning tube bundles are usually held in a range of convenient lengths. The majority of cleaning operations are carried out using 18 ft., 20 ft. or 22 ft. (5.5, 6, or 7 meters) lances with outside diameters equal to those of the nozzle being used



Rigid lancing requires the operator to feed the lance into rows of tubing such as in a heat exchanger and then hydraulically “drive” the lance through the tube while connected to a high pressure water system which delivers water at high pressure to the nozzle attachment



In some cases when using long lances or under awkward conditions, the operator will require assistance in handling the lance



Pages 20 of 28


13.1


Do’s And Don’ts Of Rigid Lancing

Do

Do Not

Shield the back of the exchanger or barricade the surrounding area to protect personnel from the spray.

Lance tubes above shoulder level. Elevate the work platform so the operator can be in a comfortable stance when operating the equipment. Failure to do so can reduce the effectiveness of the protective equipment and unnecessarily tire the operator.

Be prepared for hydraulic back pressure which results from plugged tubes. When this occurs, the lance will tend to back out of the tube. The water should be dumped immediately when this happens.

Move the lance from one tube to another with the water under pressure. Release the foot valve, dumping the pressure, then remove the lance and insert in the next tube before reengaging the valve. Failure to do this will expose the operator to the cutting jets.

Operator of the rigid lance is to remain in control of the rigid lance equipment at all times when the lance is being used.

Version No 1.0



Pages 21 of 28


14

Version No 1.0


Appendix 1 Checklist To Start And Operate HPWJ



Pages 22 of 28


15


Responsibilities Refer Section 5

16

17

18

Associated Documents 

Relevant State and Federal Legislation, Standards and Codes of Conduct



HSEQ.PRO.Risk Management and applicable



Standard Operating Instructions specific to the equipment being used



Manufacturer’s maintenance and operation instructions specific to the equipment being used

References 

Australian/New Zealand Standard AS/NZS 4233.1 “High Pressure Water (Hydro) Jetting System



Part 1: Guidelines for Safe Operation and Maintenance; and



Australian/New Zealand Standard AS/NZS 4233.1 “High Pressure Water (Hydro) Jetting Systems



Part 2: Construction and Performance



Australian/New Zealand Standard AS/NZS 4024 Machine Guarding and Contract Resources machine guarding procedure.

Environmental Impacts And Aspects Statement Please refer to the appropriate Environmental Impacts and Aspects Statement on SharePoint

Version No 1.0



Pages 23 of 28



Competency Assessment No.

Questionnaire

C/NYC

Q1

When should the fail-safe control be tied down?

A1

Never

Q2

Why must hose connections have a secondary joining mechanism?

A2

To prevent whipping

Q3

What is the purpose of the dead man switch?

A3

For the immediate dumping of pressure from the gun

Q4

When lancing, who is responsible for operation of the foot operated fail-safe control?

A4

The Lance Operator

Q5

Identify all 7 PPE items required when hydro blasting?

A5

Hard Hat, Safety Goggles, Face Shield, Hearing Protection, Heavy Duty Rain Suit Or HPWJ Suit, Protective Gloves, Safety Rubber Boots

Q6

Because of the excessive back thrust generated by HPWJ Operations only A frames are acceptable as work platforms true or false?

A6

False

Q7

When is it safe to tie down or lockdown the fail safe control?

A7

Never

Q8

Who is responsible for authorising JSEA’s?

A8

The Supervisor and the client

Q9

What is the only approved fail safe control?

A9

The dump valve

Version No 1.0



C / NYC

Pages 24 of 28



Competency Assessment Q10

In what scenario would you be required to place barricades and warning signs in excess of 5 metres from the worksite?

A10

When there is a likelihood personnel may be struck by water or debris

Q11

What must be considered when locating the truck/pump?

A11

Minimising the length of the hose

Q12

Quick connect fittings are appropriate to what pressure level?

A12

Less than 20k rated equipment

Q13

How are hose conditions verified?

A13

Through pre start checklists

Q14

Why must minimum crew size exceed two persons?

A14

A crew member must be available at the pump to de-pressurise it or a activate remote cut off switch/device

Q15

What is considered a safe distance between the hydro blast nozzles and an operator while HPWJ is in progress?

A15

7 metres , no one is to be within 7 meters in any direction of the hydro blast nozzle(s) or of an operator while HPWJ is in progress

Q16

In what situation is a solid barricade a must?

A16

Manually operating a HPWJ gun or flexi lance

Q17

Why should lance tubes not be held above shoulder level?

A17

It reduces the ability of the operator to control the flexi lance Procedure

Date

High Pressure Water Jetting Employee is competent in undertaking this procedure?

Yes

Employee Name :

Signature :

Trainers / Assessors Name :

Signature :

Version No 1.0





No



Pages 25 of 28

k AssedfrwrerewRisk AssessmenyRiskRisk Assessment

Procedure

Audit Date:

Audited by :

Location of Audit:

Manager/Supervisor:

Procedure: High Pressure Water Jetting

Item

Question

1.

All technicians have read and understand this procedure

2.

A JSEA has been completed prior to commencement of operations

3.

Correct PPE is worn at all times?

4.

Where manual flexi lancing operations are being conducted a JSEA has been prepared and approved by the General Manager?

5.

All HPWJ Operators have successfully completed the IFAP introduction to Hydro blasting Certificate Course?

6.

Persons not involved in cleaning are observing the exclusion zone

7.

Operating pressure is not exceeding rated pressure of equipment

Version No 1.0


Evidence Sited

Comments

Author Mike Fitzpartrick

Conformance Score 0,3,5

Pages 26 of 28

Audit Date:

Audited by :

Location of Audit:

Manager/Supervisor:


Item

Question

Evidence Sited

8.

Checklist to operate equipment has been completed and signed

9.

Appropriate barricading and signage consistent with this procedure is in place?

10.

HPWJ Equipment is earthed/bonded?

11.

Operators are carrying emergency medical alert card on their persons

12.

Hazardous objects have been cleared from work area?

13.

There are a minimum of two operators within the worksite at all times?

14.

The operator maintains the direction of the gun away from people at all times?

Version No 1.0


Comments



Pages 27 of 28

Audit Date:

Audited by :

Location of Audit:

Manager/Supervisor:


Item

15.

Question

Evidence Sited

Comments


Appropriate shielding is in place as per the procedure

AUDITOR’S SIGNATURE:

CONFORMANCE SCORE:

/ 75

0 – Non Conformance 3 – Continuous Improvement Opportunity

SAFETY REP’S SIGNATURE:

Version No 1.0

CONFORMANCE %:


5 – Total Conformance


Pages 28 of 28

High Pressure Water Jetting

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