Petrol Filling Stations- Construction and Operation_2

7/27/2019 Petrol Filling Stations- Construction and Operation_2

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Health c SafetyExecutive


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Petrol filling stations: Construction

and operatibn

Health and Safety series booklet HS(G)41

Contents

Foreword iii

1 .

Introduction 1

Scope 1

Glossary 1

Legal requirements: The Petroleum (Regulation) Acts 1928 and 1936 -arrangements for licensing, enforcement and appeals 3The Petroleum (Regulation) Acts 1928 and 1936 3Arrangements for licensing and enforcement 3Arrangements for appeals 3

Other legal requirements 3Legal requirements enforced by licensing authorities 3Legal requirements enforced by other authorities 4

Hazardous characteristics of petrol 5

Hazardous area classification 5

Part 1 Planning, construction and installation 13

Part 2 Operations and maintenance 31

Part 3 The electrical installation, equipment and testing 39

Appendix 1 Suggested register for petrol filling stations 53

Appendix 2 Elements of training for persons employed at petrol fillingstations 60

Appendix 3 Checklist for visual examination of electrical installations 62

Appendix 4 Guidance for annual inspections and testing of electricalinstallations 63

Appendix 5 Notes on measuring earth fault loop impedance and test pointprovisions 66

Appendix 6 Bibliography 67

HSE BOOKS


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0 Crown copyright 1990Applications for reproduction should be made to:

Copyright Unit, Her Majestys Stationery Office,

Stelements House, 2- 16 Colegate, Norwich NR3 1BQFirst published 1990

Reprinted 1991, 1992, 1993, 1995, 1996, 1997, 1998

ISBN 0 7176 0461 6All rights reserved. No part of this publication may be

reproduced, stored in a retrieval system, or transmitted in

any form or by any means (electronic, mechanical,

photocopying, recording or otherwise) without the prior

written permission of the copyright owner.

This guidance is issued by the Health and Safety Executive.

Following the guidance is not compulsory and you are free

to take other action. But if you do follow the guidance you

will normally be doing enough to comply with the law.

Health and safety inspectors seek to secure compliance

with the law and may refer to this guidance as illustrating

good practice.

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Foreword

This booklet was prepared by a working partywhich met under the auspices of the Health andSafety Executive. Membership of the workingparty included representatives from the Institute ofPetroleum, the Petrol Pump Manufacturers

Association, the Motor Agents Association, theLocal Authorities Coordinating Body on TradingStandards, the Association of County Councils, theNational Inspection Council for ElectricalInstallation Contracting, Insurance Associationsand HSE.

The booklet supersedes the Model Code of

Principles of Construction and LicensingConditions (Part I): Petrol Filling Stations whichwas prepared in 1968 under the auspices of theHome Office.


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Introduction

1 This publication gives guidance on theplanning, design, construction, operation andmaintenance of petrol filling stations. It describesstandards and methods of work aimed at:

(a ) minimising risks to operators and membersof the public at or near petrol filling stationsof fires and explosions from petrol;

(b) guiding persons involved in the planning,design, construction and alteration of petrolfilling stations on the standards necessaryfor the grant by a licensing authority under

the Petroleum (Consolidation) Act 1928 ofa licence to keep petrol;

(4 informing persons involved in the operationand maintenance of petrol filling stations of

, the conditions necessary for the safekeeping of petrol.

2 The guidance is divided into three parts:Part 1 on general design and constructionalmatters; Part 2 on operational and maintenanceactivities; and Part 3 on the specialised design,constructional and testing features for electricalinstallations at petrol filling stations. All three Partsset safety standards and practices for consistentapplication throughout the country with effect fromthe date of publication. They do not preclude theuse of alternative designs, materials or methodswhere that use provides equivalent or higherstandards of safety. Each case should beconsidered on its merits. Any variations whichappear to be necessary because of specialcircumstances or developments in technologyshould be agreed with the licensing authority.

3 The guidance on design and constructionalmatters in Parts 1 and 3 should not be applied

rigidly to existing petrol filling stations unlessredevelopment is taking place or new plant orequipment is being installed. Generally, onlyalterations which are reasonably practicable shouldbe made, taking into account the risks presented atthe filling station and the cost and feasibility ofadditional precautions. Nevertheless, the guidanceon operational, maintenance and testing activities inParts 2 and 3 should be applied at all petrol fillingstations with effect from the date of publication.

4 Legal requirements, guidance literature andstandards referred to in the guidance are listed in

Appendix 6. They are subject to amendment or

revision from time to time; references to themshould be read as references to the latest editions.

Scope

5 The guidance deals with installations wherepetrol is kept and dispensed as fuel for motorvehicles on forecourt areas to which members ofthe public have access, It is also relevant toinstallations where petrol is kept and dispensed forcommercial vehicles only and to which members ofthe public do not have access, but only to theextent that it is appropriate taking into account theparticular circumstances at an individualinstallation. It does not deal with installations atharbours and airports used primarily for fuellingboats and aircraft.

6 The guidance is directed at the safe keepingof petrol. It covers other activities (eg unloading ofpetrol from road tankers, retail shops etc) andother substances (eg diesel fuel, LPG) only to theextent that the presence of those activities andsubstances might increase risks of fires orexplosions involving petrol. It does not deal indetail with the toxic risks of petrol.

Glossary

7 Explanations of particular terms used in thisguidance are as follows:

BASEEFA. British Approvals Service for ElectricalEquipment in Flammable Atmospheres.

Class I and Class II electrical equipment.Equipment constructed in particular ways to protectagainst electric shock.

Competent person.A person with enough practicaland theoretical knowledge and actual experienceto carry out a particular task safely and effectively.The person should have the necessary ability inthe particular operation of the type of plant and

equipment with which he or she is concerned, anunderstanding of relevant statutory requirementsand an appreciation of the hazards involved. Thatperson should also be able to recognise the needfor specialist advice or assistance when necessaryand to assess the importance of the results ofexaminations and tests in the light of their purpose.

A person can be taken to mean more than one, ora body corporate or incorporate. It is thereforepossible to appoint appropriate organisations (eginsurance companies or inspection bodies) to carryout tasks designated for competent persons.

Controlpoint.A position in a kiosk or other building

at an attended self- service filling station fromwhich an attendant can adequately view and


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supervise activities at the dispensing equipment,activate the equipment and shut it off in an

emergency.

Dispenser. A measuring system similar to ametering pump (see below) except that it does notincorporate its own pumping system.

Filling station. Premises at which petrol isdispensed into the fuel tanks of motor vehicles orinto containers and which may be operated in oneof the following modes:

Attendant operated.A filling station where anattendant directly operates and controls thedispensing equipment and the discharge nozzle;

Attended se/f-service.A filling station wherecustomers operate the dispensing equipmentwhich is activated, supervised and may be shut offin an emergency by an attendant in a control point;

Unattended self-service.A filling station wheredispensing equipment is activated and operated bycustomers without supervision by an attendant.

F/ash point. The temperature for a flammable liquidat which sufficient vapour is released from theliquid to ignite when a naked light is applied to it

under standard test conditions.

GRP. Glass reinforced plastic.

Hazardous area.An area where flammable orexplosive gas or vapour-air mixtures (often referredto as explosive gas-air mixtures) are, or may beexpected to be, present in quantities which requirespecial precautions to be taken against the risk ofignition.

Hydrostatic testing. The testing of a vessel bymeans of a pneumatic test in which the explosiveenergy which would be released on failure is

reduced by almost filling the vessel with water.

/EE Wiring Regulations. Recommendations by theInstitution of Electrical Engineers which are non-statutory but are widely recognised and acceptedas guides to good practice for the design,selection, erection, inspection and testing of certainelectrical installations. Generally they apply to twodefined voltage ranges. They are not relevant tomethods of dealing with the fire and explosionhazards of electrical installations and equipment inhazardous areas (such methods are covered byBS 5345). New editions are issued from time to

time (eg a 14th Edition was issued in 1966, a 15thEdition in 1981) and are amended betweeneditions. References in this guidance to the IEE

Wiring Regulations make clear which editionsshould be followed.

impact check valve.An impact and/or heatactivated device which closes to prevent flow froma pressure source and remains closed afteractivation.

Interceptor.A device installed in a surface waterdrainage system to se arate out any petrol andthus prevent it reachin % pubfic.drains, sewers orwater courses.

Leak detector system. A system designed to closedown a pump which will remain closed when a leakoccurs in the pressurised pipework which it protects.Licensing authority. The body described in para 10for the place in which a filling station is situated.

Metering pump.A measuring system designed todispense liquid fuel into fuel tanks. It contains itsown pumping system to draw fuel from a supplytank or tanks.

Noncombustible material. Material which can beclassified as noncombustible when tested fornoncombustibility in accordance with BS 476Part 4. Alternatively, material which when tested in

accordance with BS 476 Part II does not flame andgives no rise in temperature on either the centre(specimen) or furnace thermocouples.

Nozzle. A device for controlling the flow of fuelduring a dispensing operation.

Off-set filling pipe.A filling pipe for a tank or tankcompartment which leads from a tank to aconnection point for a road tanker delivery hose atsome distance from the tank.

Petrol or petroleum-spirit. Petroleum which, whentested in accordance with the Petroleum

(Consolidation) Act 1928, gives off a flammablevapour at a temperature of less than 23OC (73OF).Remote pump.An electrically driven suction pumpassembly mounted above or adjacent to a supplytank and remote from a dispensing facility. Theinter- connection is made by a pressurised deliverypipe protected by a leak detector valve or by othermeans.

Submersible pump.An electrically driven pumpimmersed in the liquid fuel storage tank.

Vapour balancing system. A system which allowsvapour displaced from storage tanks during deliveryof petrol from a road tanker to be directed to that

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tanker via a vapour return hose. It ensures there isminimal discharge of vapour to atmosphere during

tanker delivery.

Zone. The classified part of a hazardous arearepresenting the degree of likelihood of explosivegas-air mixtures being present.

Legal requirements: the Petroleum

(Regulation) Acts 1928 and 1936 -arrangements for licensing,

enforcement and appeals

The Petroleum (Regulation) Acts 1928 and 1936

8 Under the Petroleum (Consolidation) Act1928, the keeping of petrol must be authorised bya licence and must accord with any conditionsattached to that licence. The Petroleum (Mixtures)Order 1929, the Petroleum (Carbide of Calcium)Order 1929 and the Petroleum (Liquid Methane)Order 1957 extend the requirements of the Act tothe keeping of other substances. A notice of anyconditions of licence which are to be observed bypersons employed must be displayed in an easilyreadable form and position at the filling station.Contravention of the requirements, including the

pulling down of a notice, are offences under theAct.

9 The Petroleum (Transfer of Licences) Act1936 enables a licensing authority to transfer alicence from one occupier to another. Fees for thegrant, renewal and transfer of licences arechargeable by licensing authorities according tothe rates set out in Regulations which are revisedannually on or about the beginning of eachfinancial year.

Arrangements for licensing and enforcement

10 In general, licensing authorities for fillingstations are the fire and civil defence authorities inGreater London, Greater Manchester, Merseyside,West Midlands, Tyne and Wear, South Yorkshireand West Yorkshire; county councils elsewhere inEngland and Wales; and regional and islandscouncils in Scotland. However, the responsibilitiesfor licensing fall to harbour authorities for fillingstations in harbour areas and to the Health andSafety Executive for filling stations at any site whichis subject to the Notification of InstallationsHandling Hazardous Substances Regulations 1982.

11 The functions of licensing authorities includethe assessment of individual filling stations with aview to deciding whether or not the first grant or

subsequent renewal of a licence is appropriate andwhat conditions should be attached to that licence.

Licensing authorities will be guided by thestandards and practices set out in this guidance,taking into account the objectives described inparas 1 to 3.12 All licensing authorities have powers underthe Health and Safety at Work etc Act 1974 (HSWAct) to enforce the requirements of the Petroleum(Consolidation) Act 1928. Wheri an inspectorappointed by a licensing authority visits a fillingstation his aim is to ensure the observance,maintenance and, where necessary, improvementof safety standards. In so doing, he seeks to

secure compliance with the law, including anyconditions attached to a licence. If any action isrequired, a wide variety of options are open to him.They range from informal procedures such as oralor written advice to formal procedures such asrefusal to renew a licence, variation of conditionsattached to a licence, the issue of improvement orprohibition notices under the HSW Act, and/orprosecution.

Arrangements for appeals

13 Under Section 44 of the HSW Act, anyperson who is aggrieved by a decision of a

licensing authority in connection with a licence hasa right of appeal to the Secretary of State forEmployment. Decisions on licences for fillingstations which may give grounds for appeal includerefusing to grant, renew or transfer a licence andsetting, or varying or refusing to vary, any term,condition or restriction attached to a licence.Appeals should be addressed to the Secretary ofState, Department of Employment, HS 1. CaxtonHouse, Tothill Street, London SW1 H 9NF.14 Section 44 of the HSW Act does not coverappeals against improvement and prohibition

notices which an inspector may use forenforcement purposes (see para 12). Appealsagainst such notices are governed by Section 24of the HSW Act and should be made to anindustrial tribunal on form IT 19. In practice, aninspector normally issues form IT 19 and itsaccompanying explanatory leaflet when he issuesa notice.

Other legal requirements

Legal requirements enforced by licensingauthorities

15 Other legal requirements which arerelevant to filling stations and which are enforced

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by the licensing authorities described in para 10include:

(a) the Petroleum-Spirit (Motor Vehicles &c.)Regulations 1929 and the Petroleum-Spirit(Plastic Containers) Regulations 1982: theRegulations set strict storage conditions onthe keeping without a licence of smallamounts of petrol in metal and plasticcontainers by any person intending to usethe petrol for an internal combustion engineand not wholly or partly for sale. They allowup to two metal containers of a capacity notexceeding 2 gallons each and up to twoplastic containers of a capacity not

exceeding 5 litres each to be kept in a motorvehicle, provided that the containers meetthe requirements in the Regulations formarking or labelling and standards ofconstruction. Guidance on the requirementsfor testing and marking or labelling of plasticcontainers is available in Approved Code ofPractice COP 6;

(b) the Public Health Act1961 (Section 73) andthe Civic Government (Scotland) Act 1982(Section 94): both requirements place dutieson the occupiers or owners of land orpremises to take all reasonably necessary

steps to prevent danger from disused orderelict fixed tanks or containers which havebeen used for storing petrol;

(c) the Dangerous Substances (Conveyance byRoad in Road Tankers and Tank Containers)Regulations 1981 (Regulation 20 andSchedule 4): the detailed requirements coverthe unloading of petrol from road tankers intostorage tanks. They place specific duties ontanker drivers, licensees and persons incharge of storage tanks at the time ofunloading. General guidance on unloading isavailable in the Approved Code of Practiceon the operational provisions of the 1981Regulations.

Legal requirements enforced by otherauthorities

16 In addition, a wide range of legalrequirements enforced by other authorities underthe HSW Act apply generally or in particularcircumstances at filling stations. Such authoritiesare determined by the Health and Safety (Enforcing

Authority) Regulations 1989 and are normally localdistrict or borough authorities or HSE.

17 The most important of these requirementsare the general duties of the HSW Act:

(a )

(b)

Cc)

(4

(e)

Section 2, which places a duty on everyemployer to ensure, so far as is reasonablypracticable, the health, safety and welfare ofhis employees. The duty includes, inparticular, the provision and maintenance ofsafe plant and systems of work;arrangements for ensuring safety during theuse, storage etc of articles and substances;the provision of adequate information,instruction, training and supervision; themaintenance of any plade bf work in a safecondition, with safe access and egress; andthe provision of a working environmentwithout risks to health and with adequatewelfare arrangements;

Section 3, which requires every employerand self-employed person to conduct hisundertaking so as to ensure, so far as isreasonably practicable, that persons not inhis employment are not exposed to risks totheir health and safety;

Section 4, which places a duty on everyperson who has, to any extent, control ofpremises used by persons who are not hisemployees but who use the premises madeavailable to them as a place of work or as aplace where they may use plant or

substances provided fortheir use there. Theduty includes the provision, so far as isreasonably practicable, of safe means ofaccess and egress and safe plant andsubstances;Section 6, which places a duty on everydesigner, manufacturer, importer, supplier,installer or erector of an article for use atwork. The duty includes the need to ensure,so far as is reasonably practicable, thatarticles are designed, constructed, installedor erected so as to be safe and without risksto health in reasonably foreseeablecircumstances of use, setting, cleaning andmaintenance and that adequate informationis provided to the user to secure safety insuch circumstances. Manufacturers,suppliers and importers are under a similarduty for the safety of substances, and theprovision of information to secure safetyduring use, handling, processing, storageand transportation. The duty applies to allsubstances used at work or made availableat premises to which Section 4 of the HSWAct applies;

Section 7, which requires all employees to

take reasonable care of themselves and ofothers who may be affected by what they door fail to do at work; and to co-operate with

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(f

18

(4

(b)

Cc)

(4

(e)

(f

employers to enable legal requirements tobe complied with;

Section 8, which places a duty on all peoplenot to interfere with or misuse anythingprovided for health, safety and welfarepurposes.

Other relevant legal requirements include:

the Safety Signs Regulations 1980. Therequirements provide that a safety sign (ie asign combining geometrical shape, colourand pictorial symbol to provide health orsafety information or instruction, whether ornot any text is also included) for persons atwork should comply with BS 5378 Part I.Advice is available in HSE Guidance BookletHS(R)7;the Classification, Packaging and Labellingof Dangerous Substances Regulations1984 and the Road Traffic (Carriage ofDangerous Subsfances in Packages etc)Regulations 1986. The Regulations includerequirements for container labels andvehicle markings which may be met duringactivities at filling stations. Advice isavailable in HSE Guidance Booklets

HS( R)22 AND HS( R)24;the Reporting of Injuries, Diseases andDangerous Occurrences Regulations 1985.The Regulations set out the types ofincidents which must be reported and howand to whom reports must be made. Adviceis available in HSE Guidance BookletHS(R)23;the Control of Substances Hazardous toHealth Regulations 1988. The Regulationsrequire employers to assess the risks arisingfrom hazardous substances at work and the

measures needed to protect employeeshealth, and to take appropriate action toprevent or adequately control exposure;

the Electricity at Work Regulations 1989.The Regulations impose requirements aboutelectrical systems and equipment, includingwork activities on or near electricalequipment. Advice is available in HSEGuidance Booklet HS(R)25;the Factories Act 1961 and the Offices,Shops and Railway Premises Act 1963. Both

Acts include requirements which may berelevant to activities at or associated withpetrol filling stations.

Hazardous characteristics of petrol

19 Petrol is a highly flammable liquid and givesoff flammable vapour even at very lowtemperatures. Released vapour, when mixed withair in certain proportions, forms a flammableatmosphere which burns or explodes if a source ofignition is present, A flammable atmosphere existswhen the proportion of vapour in the air is betweenapproximately 1% (the lower flammable, orexplosive, limit) and 8% (the upper flammable, orexplosive, limit).

20 Petrol vapour is heavier than air and doesnot disperse easily in still air conditions. It tends tosink to the lowest possible level of its surroundingsand may accumulate in tanks, cavities, drains, pitsor other depressions. Petrol floats on the surface ofwater; it may therefore be carried long distancesand create a hazard remote from its point ofrelease.

21 Flammable atmospheres may be present inthe vapour spaces of tanks containing petrol and intanks after petrol has been removed. They mayalso exist where clothing and other absorbentmaterial or substances are contaminated withpetrol.

22 Petrol vapour, even when present in theatmosphere at levels below the lower explosivelimit, can have acute and chronic effects if inhaled.The guidance does not deal with this in detail (seepara 6) but the risks from inhaling petrol vapourshould be considered in the assessment requiredunder the Control of Substances Hazardous toHealth Regulations 1988. Exposure to the vapourshould be prevented and where possible thisshould be taken into account in the planning anddesign of a filling station and during all operationswhere vapour might be present.

Hazardous area classification

23 The safe development and operation of afilling station should be based primarily on anassessment of the likelihood of flammable orexplosive atmospheres being present duringoperations; and the need to prevent, as far aspossible, sources of ignition reaching suchatmospheres. Therefore, the concept of hazardousarea classification and zoning set out for fixedelectrical equipment in BS 5345 Parts 1 and 2should be followed throughout the activitiescovered by all three parts of this guidance. All

sources of ignition, including those associated withsparks of any sort or hot surfaces of electricalequipment, should be excluded from hazardous

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areas or, in the case of electrical equipment, (c) Zone 2: other areas that may be affected byshould be specially protected. This includes both occasional spillage or release of vapour from

fixed and portable equipment. plant and equipment handling petrol.

24 BS 5345 defines the following hazard zones:

(a) Zone 0: in which an explosive gas-airmixture is continuously present, or presentfor long periods;

(b) Zone I: in which an explosive gas-airmixture is likely to occur in normal operation;

(c) Zone 2: in which an explosive gas-air mixtureis not likely to occur in normal operation and,if it occurs, it will exist only for a short time.

BS 5345 also defines the areas outside thesezones as non-hazardous.

25 The following general guide indicates howthis might be applied to different parts of a fillingstation:

(a) Zone 0: the interior of petrol tanks and ofchambers containing tank filling connections;

(b) Zone 7: the interior of metering pump anddispenser housings, the vicinity of vent

openings, and pits and other depressionsbelow ground level partly or wholly within azone 2 area;

26 The guidance in Table 1, in conjunction withguidance obtained from suppliers of the equipmentinvolved and of the petrol, should be applied todetermine the extent of the various zones. Incompiling Table 1, regard has been paid tooperational factors peculiar to filling stations (egfree access of members of thepublic and theirmotor vehicles). Consequently, the extent of someof the zones may be different from those whichwould apply at a petroleum installation whereoperational factors (eg access limited toappropriately trained persons) are different. This isconsistent with the approach recommended in BS5345 Part 2, which describes a method of carryingout an area classification procedure. Local siteconditions may mean that the extent of zones willvary in individual cases, and each site should beconsidered separately. In particular, the horizontaldistances quoted for Zone 2 areas will depend onthe likely wetted area of a liquid spillage, and thiswill vary with paving and drainage conditions andthe degree of containment from walls and otherobstructions. Also, if a location apparently fallswithin two zones, that location should be regardedas being in a zone with the higher risk.

Table 1 Hazardous area classification

Area

classification

Underground storage tanks (4 Within any tank and within any manhole chamber in which Zone 0there are tanker delivery hose connection points.

lb) Within any manhole chamber not containing tanker delivery Zone 1hose connection points.

(4 For tank filling connections, vertically for1.25m above Zone 2forecourt level, extending horizontally for 3m and coming

down to forecourt level at a radius of 4.25m from theconnections (see Fig 1).

Vent pipes for underground (4 Within a radius of 3m in all directions of the open end of any Zone 1vent pipe.

(b) The area below the Zone 1 area of the vent pipe, for a radius Zone 2of 3m around the discharge point and down to ground level

(see Fig 2).

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Area

classification

Metering pumps and (4 Within the metering pump/dispenser housing and anydispensers enclosed spaces directly connected thereto.

(b) Within approximately 3m horizontally, coning downwards to4.25m at forecourt level, of the centre line of the meteringpump/dispenser, and vertically to the top of the hydraulic

housing with a minimum height of1.25m (see Figs 3-5and zoning diagrams in BS 7117: Part 1 for exceptions

to this rule).

(c) For metering pumps/dispensers (or radial arms attachedthereto) incorporating a sight-glass, within 0.75mhorizontally from 0.15m above the sight-glass down toground level.

(4 Any canopy fitted to a low-hose metering pump/dispenser,provided adequate precautrons are taken to preventvapour from the dispenser body reaching the canopy

This is subject to the bottom of the canopy being at least1.25m above the forecourt level.

Zone 1

Zone 2

Zone 2

Non-hazardous

(safe) area

Remote pumps (4 Within any enclosure around the pump. Zone 1(b) Within 3m horizontally coning downwards to 4.25m at Zone 2

forecourt level of the centre line of the remote pump

housing and vertically to the top of the hydraulic housing

with a minimum height of 1.25m.Screwed or flanged joints

in above ground pipeworkA cylinder 1 m in diameter centred on the joint extending from 1 m

above the joint to ground, unless the pipe is in an enclosed or

essentially enclosed space in which case it is the entire space.

Zone 2

Road tankers parked for

unloading(4 Within 1 m in all directions of the centre of any tanker top Zone 1

openings, extending 2m above the tanker shell and within

300mm of the shell extending vertically down to ground level.

(b) Within 4.25m horizontally of the tank discharge connections Zone 21 m in all directions from the connections extending down to

ground level.

(c) Where the road tanker is parked under a canopy or similar Zone 2structure, within a radius of2.5m of any opening on thetank top.

Forecourts The forecourt area within a 4.25m radius of dispensers and fillingpoints up to a height of 0.25m above ground level. Zone 1

Buildings Kiosks and other small buildings with openings in a hazard zone. The appropriate

zone at the same

height throughout

the building

Pits, trenches etc.

Zone 1

Any pit, trench or depression below ground wholly or partly in a

Zone 1 or Zone 2 area.

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NOTE. The manhole chamber is classified aszone 0 only when it contains points towhich tanker delivery hoses can beconnected (see table II.

NOTE. The manhole chamber is classified aszone 0 only when it contains points towhich tanker delivery hoses can beconnected (see table II.

Fig 1 Hazardous area surrounding underground storage tank (section)

Fig 2 Hazardous area surrounding vent pipe

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Part 1 Planning, construction and installation

Planning and design 14Initial planning 14Locations of tanks, off-set filling points and pipelines 14Locations of vent pipes for underground storage tanks 75Locations of metering pumps and dispensers 15Locations of road tanker delivery stands 16Locations of buildings and other features 16

) .Construction and installation 76Construction of tanks and connections 16Installation of tanks 18Construction of pipelines and fittings 22Construction of vent pipes, including vapour balancing systems

Installation of pipelines 23Construction and installation of metering pumps and dispensersConstruction of forecourts and road tanker delivery stands 26Construction of buildings 26Construction of canopies and other features 27

Marking and identification of tanks and associated equipment 27

Fire and emergency equipment 27

Warning and information notices 28General 28Notices for customers and other visitors 28Notices for filling station employees 29

Testing, commissioning and record keeping 29Testing of all tanks 29Testing of pipelines and fittings 29Metering pumps, dispensers and associated pumping equipment 30Commissioning 30Record keeping 30

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Planning and design

Initial planning

27 Any site chosen for a filling station should besufficiently spacious for it to be designed tominimise the risks from petrol to any person likelyto be at or near the filling station. The locations oftanks, filling and vent pipes, metering pumps,dispensers, road tanker delivery stands andbuildings should be designed to provide foradequate means of escape for persons in theevent of a fire or other incident; for hazardousareas to be protected from sources of ignition; and

for safe access, routing, parking and exit ofcustomers vehicles, service vehicles and roadtankers.

28 Hazardous processes being carried out orhazardous materials being stored on land or inbuildings or other structures close to theboundaries of the filling station should be takeninto account. The locations of tanks and otherequipment and services at the filling station shouldbe chosen to minimise the effects of fire orexplosion at adjacent premises and to avoid

jeopardising the adequate means of escape ofpersons at the filling station or at adjacent

premises. Consultation with the occupiers ofadjacent premises may be necessary.

29 The nature, location and depth of any wastedisposal (landfill), any subterranean water courses,culverts, pipelines or mine workings and anycuttings or tunnels for road or rail vehicles orpedestrians directly beneath or adjacent to thefilling station should be identified and assessed forany effects on the safe keeping of petrol. Wherethe licensing authority assesses that the risksinvolved with such features justify it, a form ofsecondary containment for, and contents or leakmonitoring of, the petrol storage should beprovided. The nature of the original use of landbeing redeveloped should also be identified andassessed. Consultation with responsible publicauthorities or other organisations will usually benecessary.

30 Initial planning should also take into accountthe guidance on planning for electricity suppliesand electrical equipment in Part 3; and the need forcoordination between all persons involved in thedevelopment of the filling station, eg the developer,contractors, operator, suppliers of equipment andpetrol, installers, etc.

31 As early as possible during the planningstage, the advice of the licensing authority should

be sought. Before any work on site is started, anapplication should be made to the licensing

authority. The application should be accompaniedby a site plan (approx 1 :lOO scale) showing thelocations of tanks, pipework, metering pumps,dispensers, drainage systems, buildings and otherstructures. Work should not be started until thelicensing authority has agreed the proposedarrangements in writing.

Locations of tanks, off-det filting points andpipelines

32 Petrol storage tanks should be locatedunderground, clear of the foundations of buildings

and not within buildings or in or withinapproximately 6m of basements. The centre linesof any tank openings or off-set filling points shouldbe not less than 4.25m from the publicthoroughfare or any other boundary of the fillingstation; but where there is an imperforate wall atthe boundary extending sideways not less than 6mfrom any filling point and not less than 3m inheight, filling points may be located close to theboundary. The locations chosen should allow fortank openings or off-set filling points to be in theopen air to ensure adequate ventilation fordispersing accumulations of vapour; and to beseparated from occupied buildings by a distance

sufficient to minimise the effect of radiant heat onbuildings (eg 12m from living accommodation, 6mfrom other types of occupied buildings) unless theopenings to such buildings are themselvesadequately protected (ie to a minimum standard ofhalf-hour fire resistance). The locations of offsetfilling points should also allow for some form ofprotective construction (see para 73).33 Pipelines from tanks to off-set filling points,metering pumps, dispensers and vent pipes shouldbe routed below the ground surface. The routeschosen should not be under buildings or otherobstructions so that access to the pipelines can begained if a need arises after installation. In theevent of alterations to the agreed pipeline routesshown on the original plan a final diagram shouldbe submitted to the licensing authority.

34 Tanks for flammable liquids with flash pointsof32OC and above (eg diesel fuel, paraffin) shouldbe located in a safe place in relation to the petrolinstallation. Above-ground tanks should beseparated from petrol storage tanks and otherpetrol equipment by at least the distances specifiedin Table 2. In addition, guidance in HSE GuidanceBooklet HS(G)50 about, for example, minimumseparation distances from buildings, boundariesetc, and the provision of bunds for all abovegroundtanks, should be followed.

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Table 2 Minimum distances between petrol equipment and the storage of high flash point liquids (32 and above) in above-ground

storage tanks

Tank capacity (litres)

Single ranks Total for agroup (maximum)

Minimum separation distances from

any part of a tank to filling

points of petrol tanks, vent

discharge points and metering

pumps and dispensers (metres)

up to 1000 30001ooo- 5000 150005000. 33000 10000033000- 100000 300000

Above 100000 750000

4 ) *.4

6

8

10

Table 3 Minimum distances between LPG facilities and petrol LPG cylinders and similar containers) should beequipment followed where appropriate.

LPG facilities Distance Petrol facilities Locations of vent pipes for undergroundstorage tanks

LPG tanks and 7.5m Metering pumps/dispensers,filling connections. tank vents, underground tank

manholes and fill points

LPG dispensers 7.5m Tank vents and fill points

Although the flammable liquids and LPG referred to in paras 34to 36 are not of themselves subject to licensing under the

Petroleum (Consolidation) Act 1928, the licensing authoritys

powers extend to them if, in the authoritys view, the presence of

such substances at a filling station affects the safe keeping of

petrol.

35 At commercial filling stations (ie fillingstations where the public have no access), theguidance in para 34 may also be applied to theaboveground storage of liquids with flash pointsbelow 32OC other than petrol (eg some types ofanti-freeze).

37 The extensions of vent piping above groundshould be located where vented vapour will bedispersed safely into the atmosphere. Locationsshould be chosen taking into account conditions ator near the filling station which could adversely

affect safe dispersal of any discharge and cause aflammable atmosphere to reach a source ofignition (eg the nature, height and location ofsurrounding developments; the direction ofprevailing winds and the possibility of unusual aircurrents caused by high buildings; and theproximity of possible ducts for vapour, such as roofgutters, down pipes, chimney stacks, ventilationshafts, trees, narrow passages and gaps betweenbuildings).

36 Underground, mounded or above-groundtanks for LPG should also be located where theywill not increase the risks of fires or explosions frompetrol. Minimum separation distances between LPGfacilities and petrol storage tanks and other petrolequipment are set out in Table 3. The delivery standfor the LPG tanker should be positioned so thatthese distances are not seriously reduced whenLPG is being delivered. The separation distancesshould be used in conjunction with the moredetailed advice in HSE Guidance Booklet HS(G)34(for bulk installations). In addition, detailed guidance

in LPGITA Code of Practice No 20 (for LPG vehiclerefuelling facilities), LPGITA Code of Practice No 22(for pipework) and HSE Guidance Note CS4 (for

38 Vent pipes should extend to a height greaterthan the maximum liquid level in any road tankerlikely to deliver petrol to associated tanks and, inany case, not less than 5m above ground level.The vent discharge point should not be within 3m,in any direction, of opening windows or any otheropening to a building. Vent pipes should be notless than 3m from a boundary; but where there isan imperforate wall at the boundary extending fromground level and for at least 3m in any directionfrom the vent discharge point, they may be locatedclose to the boundary.

Locations of metering pumps and dispensers

39 Metering pumps and dispensers should be

located in the open air where they will beadequately ventilated. The centre lines of theirhousings should be not less than 4.25m from the

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public thoroughfare or other boundary of the fillingstation. They should be separated from occupied

buildings by a distance adequate for protectionagainst the entry of fire (eg 9m from livingaccommodation, 6m from other types of occupiedbuildings) unless the openings to such buildingsare themselves adequately protected. They shouldbe positioned so that vehicles can be parked easilyin a convenient position alongside each dispenserwithout restricting the movement of other vehicles;and so that hoses do not have to be extendedunduly and are not likely to be damaged by contactwith stanchions or other obstructions. At attendedself-service stations, metering pumps anddispensers should also be located where vehicles

etc being filled from them can be adequatelyviewed and supervised from the control point.

Locations of road tanker delivery stands

40 The road tanker stand for delivering petrolinto storage tanks should be in the open away frombuildings (excluding canopies), dispensingactivities and emergency escape routes. It shouldbe large enough to allow a road tanker to bepositioned wholly within it during delivery (ie notless than 15m long and 5m wide at any point). Thelocation chosen should allow for the road tanker tobe positioned so that it has a clear and

unobstructed escape route in a forward direction.The stand should be level with sufficient clearanceabove the tanker from any overhanging obstructionto permit dipping (see also para 44) and access tofoot valve controls.

Locations of buildings and other features

41 Any building intended for use as a controlpoint at an attended selfservice filling stationshould be located where an attendant at thecontrol point can exercise adequate supervisionover dispensing activities. The view from thecontrol point necessary to ensure adequatesupervision of dispensing activities shouldtherefore not be obscured by other buildings orstructures or by a road tanker properly positionedfor delivery of petrol into storage tanks (see alsoparas 126 and 127).42 A building intended for use as a shop forconsumer goods and other services (includingshops known as convenience stores) may attractto the filling station large numbers of customers notassociated with petrol sales. As far as possible, thelocation of the building, together with anyassociated design features, should avoid the

possibility of such customers affecting the safeoperation of petrol dispensing or road tankerdelivery. Ideally, there should be two entrances to

the shop, one from the forecourt for customers forpetrol sales and one remote from the forecourt for

other customers; and parking facilities withentrances and exits away from the petroloperations. Where this is not possible, adequateseparation between the petrol operations andpedestrians and vehicles visiting only the shopshould be achieved by the provision of clearlymarked routes and parking areas.

43 Vending machines $nd other facilities notrelated to the dispensing of petrol should belocated so that customers use of them and accessto them do not adversely affect the safe operationof petrol dispensing or road tanker delivery.

44 The need for the openings to storage tanks,off-set filling points, pipelines, metering pumps anddispensers to be in the open air (see paras 32, 33and 39) does not prevent the location of a canopyover a filling station forecourt provided that thedimensions of the canopy do not adversely affectthe ventilation of or access to the equipment. Anycanopy should not prevent the dipping of a roadtanker properly positioned for delivery of petrol intostorage tanks.

45 Petrol interceptors should always be installedand should be located where they will prevent the

drainage of any petrol spillages or watercontaminated with petrol from entering any watercourses, public drains or sewers or from otherwiseescaping from the filling station. Locations shouldbe chosen taking into account that water drainingfrom car wash facilities should not pass through thepetrol interceptors; that by-pass interceptors will notcope with large spillages and are therefore notsuitable for filling stations; that the capacity ofinterceptors should be adequate to contain at leastthe maximum contents of a compartment of a roadtanker likely to deliver petrol at the filling station;and that each chamber should be vented. Ventpipes should extend to not less than 2.4m aboveground level, should be not less than 75mmdiameter and of robust construction, and should bemanifolded above ground.

Construction and installation

Construction of tanks and connections

46 Underground mild steel storage tanks shouldbe designed, manufactured, inspected and testedin accordance with BS 2594 or other appropriaterecognised standard. Each tank or, in the case of

multi-compartment tanks, each compartment,should be fitted with a manhole of the dimensionsdescribed in BS 2594 and fitted with adequate

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protection against damage to the bottom of thetank from any dipstick (eg a steel plate of 6mmthickness and adequate area welded inside thebottom of the tank beneath each dip pipe duringmanufacture).

47 Alternatively, underground GRP tanks maybe used provided that they are manufactured,inspected and tested according to BS 4994(Category I) and that, until a recognised standardspecific to GRP tanks for underground use isdeveloped, the special considerations set out inthis guidance are followed. Chemical resistancetesting of the resin to be used for the tanks (seeBS 4994, clause 6.5) and prototype tank testing

(see BS 4994, clause 38.3) should be performed

as set out in Table 4; and prototype tank testingshould be witnessed by an independent assessor(see BS 4994, clause 38.1). Each tank orcompartment should be fitted with a bolted steelneck or a neck of flame retardant material (ie itshould achieve a class 1 rating under BS 476Part 7) and with adequate protection againstdamage to the bottom of the tank or compartmentfrom any dipstick. It should also be fitted with ametal plate which is electrically bonded to the steeltank lid; is in such a position in the base of the tankor compartment that any liquid contents will be incontact with it; and is of such a size that any liquidcontents will be no more than 2m from it (seeBS 5958 Part 2).

Table 4 Chemical resistance and prototype testing for underground GRP tanks

/tern Test Method

Resin Chemical resistance Representative specimens of resin laminate should be immersed in an appropriate

reference fuel for 28 days at 38C. After 28 days, the tensile strength, flexural strengthand lzod impact resistance (as determined by the appropriate method in BS 2782) must

be not less than 80% of that of identical control specimens stored in air at 22OC(?2OC)for the same period.

Prototype

tank

Earth load The tank should be installed in a pit and supported on appropriate granular bedding

material (see paragraph 56). The pit should be backfilled with similar material to a

depth of900mm (+ 75mm) above the tank. The tank should not leak, fail or show adeflection of more than 2% of the vertical diameter of the unloaded tank when

measured at a fitting near the centre of the tank (see ASTM D.4021-86, item 6.4.1).

Prototype

tank

Concentrated load The tank should be installed as described for the earth load test. A concentrated load

should be applied at the mid-span of the tank (by hydraulic or other means) to a load

bearing plate 500mm square on the top of the covering backfilling material equivalent to

500kg in excess of the current maximum permitted axle loading for a road tanker. The

tank should perform as required by the earth load test (see ASTM D.4021.86,item 6.4.2).

Prototype

tank

External pressure The tank (empty) should be installed as described for the earth load test. The pit should

be backfilled to the level described for the earth load test and filled with water to the

same level. The water level should be maintained for 24 hours. During this period, the

tank should perform as described for the earth load test.

Prototype

tank

Water load The tank should first be subjected to an air pressure test to 0.35 barg and wiped with a

soap solution to test for soundness (see guidance on safety in pressure testing in HSE

Guidance Note GS4 and BS 4994, clause 39.7). The sound tank should then be

installed in a pit. The pit should be backfilled to the level of the top of the tank and the

tank filled with water. The tank should be subjected to an air pressure test to 0.7 barg

for at least 1 hour and should maintain that pressure during that period.

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48 Each tank or compartment should be fittedwith connections for filling, discharging and

venting. Openings should be limited to thosenecessary for fitting those connections and, ifappropriate, for automatic contents measuringequipment. The filling pipe should be carried downinside the tank to not less than 40mm from thebottom of the tank or as near the bottom aspossible; the discharging pipe should terminate notless than 35mm above the bottom of the filling pipeto maintain a liquid seal. The delivery end of eachfilling pipe, whether the pipe is fitted for filling at thetank or compartment or at an offset filling point,should be fitted with a screw-on or snap-onlockable cap, provided with a suitable washer,

incorporating, where appropriate, a separatecapped aperture for a dipstick. Any openingassociated with automatic contents measuringequipment should be capable of closure in a waywhich will prevent unauthorised access.

49 Each tank or compartment should be fittedwith accurately calibrated means for measuring itscontents. If a dipstick is to be used as the means,that dipstick should be made of brass, wood (with aprotected end), GRP or other material which willnot cause a spark when in contact with the tank,tank connections or tank surroundings. A dipstickmay only be used in a direct filling connection; in

the case of filling through off-set filling points,automatic means of measuring contents should befitted. In order to avoid spillage resulting from abuild up of back pressure, contents gauges shouldnot be installed in a filling pipe or vent pipe.

50 Each tank or compartment should also befitted with means for removal of accumulations ofwater. The means should be either through a directfilling pipe or, where an off-set filling point is used,by the insertion of a T-piece in the filling pipe withthe unconnected end securely plugged. Any plugarrangements should be removable only by theuse of tools.

51 Before each steel tank is lowered into itsexcavation ready for installation, it should becleaned of all exterior rust and scale andadequately protected against corrosion, eg by theapplication of one coat of red lead (BS 2523,composition Type B) followed by one coat ofbitumen, or by the application of two coats ofbituminous paint (BS 3416 or BS 6949). Any otherform of protection which might be proposed shouldbe the subject of specialist advice.

52 Any above-ground tanks for flammable

liquids (see paras 34 and 35) should be designed,manufactured, inspected and tested in accordancewith BS 2594, BS 2654 or other appropriate

standard of good practice. Tanks should beprotected from corrosion according to, for example,

BS 5493. Further guidance about above-groundtanks is in HSE Guidance Booklet HS(G)SO. Anystorage tanks for LPG (see paragraph 36) shouldbe in accordance with the standards in LPGITACOP No 20 and HSE Guidance Booklet HS(G)34.Installation of tanks

53 Each underground steel tankshould beinstalled in an excavation ahd, with the exceptionof the tank or compartment manhole lid, should besurrounded by concrete not less than 150mm inthickness unless effective secondary containment(eg double skinned tank, specialised excavation

liner) and contents monitoring are provided. Wheresecondary containment is provided, the excavationmay be backfilled as described in paragraph 56.

Any concrete or infilling above the tank should bereinforced to withstand vehicular traffic. Each tankshould be supported by a reinforced concrete baseslab not less than 150 mm in thickness withsuitable fixing points for tank anchoring straps.

54 Each manhole lid for a steel tank and anyopening within the manhole, other than the uppertermination of any off-set filling pipe and vent pipe,should be enclosed in a chamber of concrete withwalls of not less than 150mm in thickness or of

other impermeable material capable of retainingany petrol spillage. Brickwork is not suitable. Eachchamber should be fitted with a cover which isstrong enough to withstand vehicular traffic andwhich is watertight or raised sufficiently aboveground level to prevent the entry of surface water.Diagrams of typical steel tank installations are atFigs 6 and 8.

55 Concrete for the tank surround and manholechambers should be made of one of the prescribedmixes for ordinary structural concrete in Section 6of BS 8110 to the standard set out in Table 5.

Table 5 Concrete for tanks etc

Grade designation C3OP

Type of cement Sulphate resisting Portland cement

(BS 4027) or other sulphate resisting

cement (BS 146, BS 4246)

Nominal maximum size 20mm

of aggregate

Workability Medium

Method of compaction Needle or surface vibration

Minimum cement content 350kg per cubic metre

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Fig 6 Typical layout ofa steel petrol tankmstallamn

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Fig 7 Typical layout of a GRP petrol tank mstallatlon -


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Fig 8 Typical layout 01 a submersiblepumpwith pressure IIWS

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56 A GRP underground tank should be installedwith the top at least 900mm below ground level or,where a concrete reinforced slab of not less than150mm thickness is installed above it as protectionfrom vehicular traffic, at least 450mm below groundlevel. It should be above a reinforced concretebase-slab of not less than 150mm in thickness andsurrounded by suitable granular backfill material ofnot less than 300mm. The concrete should beprovided with suitable fixing points for tankanchoring straps. Suitable backfill material wouldbe free flowing rounded pea gravel (ie with noparticle larger than 10mm and no more than 8% byweight capable of passing a no 200 sieve or with amix of particle sizes between 3mm and 20mm and

no more than 3% capable of passing a No 8 sieve);stone or crushed rock (ie with an angular particlesize between 3mm and 12mm and no more than3% capable of passing a No 8 sieve); or drywashed sand. In some circumstances, the materialmay need to be contained in a filter fabric toprevent migration in the backfilled excavation.

57 The manhole lid for a GRP tank should beenclosed in a chamber which should be capable ofretaining any spillage of petrol. The walls of thechamber should not transmit any surface loading tothe tank shell; and any part of the tank shellexposed within the chamber should be flame

retardant (ie it should achieve a Class 1 ratingunder BS 476 Part 7). The chamber should befitted with a cover as described in para 54. Allmetal tank lids, metal pipework etc should beelectrically bonded. A diagram of a typical GRPtank installation is at Fig 7.

58 Each excavation for a steel or GRP tankshould be made with particular care if it is in thevicinity of existing buildings or structures. It shouldprovide a firm level base for the tank; and ledgesor high spots which might stress the tank should beavoided. The sides of the excavation should beadequately shored to prevent soil or other materialfrom falling into the hole. Guidance in the HSEleaflet Safety in excavations should be followed.

59 Each tank should be lowered into theexcavation with sufficient care to avoid damage tothe tank or its protective coating. Where there is apossibility of flotation, it should be anchoredeffectively. Where metal or wire rope anchoringstraps are used with a steel tank, a layer of dampproof membrane should be placed between thestraps and the tank. Anchoring straps for a GRPtank should be of nylon or similar material to avoidabrasion or distortion of the tank shell. Before any

concreting or complete infilling takes place, thetank should be tested (see paras 98 to 102). Anychocks should be removed at the time of

concreting. Any removable shoring used in anexcavation for a GRP tank should be removed by

stages as the gravel is compacted to ensure thatno voids are left.

60 Any above ground tanks for flammableliquids (see paras 34 and 35) should be installed inaccordance with HSE Guidance Booklet HS(G)50.

Any storage tanks for LPG (see para 36) should beinstalled in accordance with LPGITA COP20 andHSE Guidance Booklet HS(G!)34. I,Construction of pipelines and fittings

61 Tubes forpipework should be manufacturedin accordance with BS 1387 to the thicknessspecified for medium tubes and, if intended for usewith petrol, should be galvanised. Pipework shouldbe constructed in accordance with a suitablestandard (eg ANSI B31.3 (with EEMUAsupplement 153) or, if welded construction isadopted, BS 2971). Joints should be kept to aminimum; those installed below ground should bewelded or screwed with a corrosion allowance builtin to design. To minimise leakage, welded jointsare to be preferred and should always be used innon-hazardous areas. Adequate protection againstcorrosion should be provided with particularattention to vulnerable areas (eg screwed joints).

Aboveground pipework may have welded, screwedor flanged joints although it should be recognisedthat any screwed or flanged joint will create aZone 2 area (see Tablel). It should be adequatelyprotected against corrosion. Any valves should beconstructed of materials which are sparkproof andcorrosion resistant. Any jointing compound shouldbe resistant to petrol.

62 Where pipework using other material suchas plastic or GRP is planned, specialist adviceshould be sought and the plan should bediscussed with the licensing authority.

63 Where a GRP underground tank is beingused, all pipeline connections within the tankmanhole chamber should incorporate flexiblesections manufactured of material appropriate totheir exposed nature within the manhole chamber(eg stainless steel). Such sections should preventdamage to pipework or connections in the event ofdifferential movement between the tank and anyconcrete-encased steel pipework. This is notnecessary if plastic or GRP pipework is used.64 A check valve should be fitted in eachsuction pipeline to restrain the fallback of petrol tothe tank or compartment between deliveryoperations or during prolonged shut down of thesystem (eg overnight). It may be fitted in the

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suction pipeline immediately above the tank lid(see Fig 6) or at the metering pump.

65 A leak detector system should be fitted witheach underground pressure delivery line from aremote or submerged pumping unit, unless thedelivery line is down stream of the meter (eg adouble walled pipe with a suitable monitoringdevice in the void). For ease of maintenance, anisolating valve should be fitted in the pressure lineat each dispenser. Fig 8 illustrates examples ofthese features.

66 An impact check valve to cut off fuel in theevent of impact should be provided in the pressure

delivery line riser at the base of each dispenser(see Fig 8 and BS 7117 Part 2). Alternatively,adequate protection from damage for thedispenser and its associated pipework (eg byplacing a riser pipe within the web of a substantialH section beam) should be provided.

Construction of vent pipes, including vapourbalancing systems

67 A separate vent pipe should extend fromeach tank or compartment, should not be less than40mm diameter and should have no dips which

might trap small amounts of petrol. Subject to theparticular conditions at the filling station (seeparas 37 and 38), each open end should beconstructed to discharge upwards. Except in thecase of vapour balancing arrangements wherespecial considerations apply (see


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concrete base. In the case of an impact checkvalve or isolating valve, the pressure line may

terminate in a shallow, liquidtight pit. The pit shouldbe constructed with walls and floor of concrete ofthe standard in Table 5 and of not less than150mm in thickness. The pit should be as shallowas possible and should in no case be deeper thanis necessary to accommodate the valve (seeFig 8).

73 Where possible, each off-set filling pipeshould be installed so that the filling connection isabout 0.3m above ground, with the terminationangled to assist connection with the road tankerdelivery hose. Each off-set filling point should be

adequately protected against impact (eg byinstalling kerbs, bollards, barriers or boxing, or byinsetting into surrounding or overhanging walls).

74 Where it is necessary to terminate an off-setfilling point below ground, it should be installed in a chamber made of concrete to the standard inTable 5 with walls of not less than 150mm inthickness. The chamber should be fitted with acover as described in para 54 above. Any change-over or isolating valves should be installed andfitted in the same way.

75 Before any concreting or infilling of

underground pipe runs takes place, all fillings,suction, syphon and vent pipes should beseparately identified and tested (see paragraphs103 to 105).

Construction and installation of meteringpumps and dispensers

76 All metering pumps and dispensers shouldbe constructed, certified and installed inaccordance with BS 7117 Parts 1 and 2 or otherequivalent standard (see also para 182). Anymetering pumps or dispensers intended for liquidsother than petrol should, if located within 6m ofequipment for petrol, conform to the samestandard.

77 In addition to the construction standards inBS 7117 Part 1, metering pumps and dispensers atunattended self-service filling stations shouldinclude a limiting device designed to prevent acontinuous outflow of petrol of more than 50 litres(the limiting device should be additional to anymoney, token or credit card pre-set device). Anindependent timing device to prevent continuousoperation of the pump for a period of more than3 minutes should also be included. Such devices

are not necessary at filling stations wheredispensing equipment is controlled or may be shutoff in an emergency by an attendant. At

unattended commercial filling stations to which thepublic do not have access, limiting devices of 100

litres may be installed but no independent timingdevices are necessary.

78 Metering pumps and dispensers should besecurely mounted on islands or plinths raisedabove the surface of the surrounding forecourt orotherwise securely fixed with adequate protectionagainst damage from vehicles. Any island shouldbe constructed of concrete kith an impact-resistantkerb.

Construction of forecourts and road tankerdelivery stands

79 Areas subject to vehicular traffic should beconstructed of materials capable of supporting theanticipated weight and intensity of traffic withoutexcessive settlement, cracking or erosion. Areasabove underground tanks and pipe runs should beadequately reinforced (see paras 53 and 71).80 The surface of any area within a radius of3.6m of metering pumps and dispensers should bepaved with non-slip concrete, or concrete blocksmanufactured in accordance with BS 6717 Part 1.Blocks should be a minimum of 80mm thicknessand should be secure against lateral movement.

Any area intended as a road tanker delivery standshould be paved with non-slip concrete.

81 Surface drainage of any area surroundingmetering pumps, dispensers and road tankerdelivery points should be arranged to carry anyspills or leaks of petrol, through trapped gullies orby channels, to petrol interceptors before drainingfrom the filling station (see para 45). Water from carwash facilities should not be channelled through theinterceptors. Interceptors should be fitted with outletpipes which are larger than the inlet pipes, ventpipes (which should interconnect above ground)and manholes with covers; and should be installedin concrete of the standard in Table 5. If necessary,manhole chamber covers and the ground surfaceabove the interceptors should be strong enough towithstand vehicular traffic.

Construction of buildings

82 Buildings should be constructed generally ofnon-combustible materials and should conform tonational and local building regulations andpractices where applicable. They should haveadequate means of escape in case of fire andshould be adequately ventilated. Floor finishes

should be non-absorbent, resistant to oil and water,and non-slip. All doors forming part of the means ofescape from any part of a building should be

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capable of being opened from inside at times whenthe filling station is open for business.

83 Doorways or other openings to buildingslikely to be affected by any spills or leaks of petrolshould be raised above the level of the surroundingground surface or protected by sills.

84 Any space heating equipment of a standardappropriate to and installed in a building in an areaclassified as non-hazardous should not beconnected to a hazardous area by means of ductsor ventilators. An exception is indirectfired heatersprovided that all incoming air is fresh and the ductsinto the area are sited at least 1.8m above floorlevel (see BS 6230 for indirectfired gas heaters).

Any equipment installed in an area classified ashazardous should be constructed to an explosion-protected standard suitable for the zone in which itis installed. Consideration should also be given toinstalling heating at a high level (ie at or close to theceiling) so that the equipment is not likely to act asa source of ignition for petrol contaminated clothing.

Construction of canopies and other features

85 Canopy structures should also beconstructed of non-combustible materials andshould conform to national and local building

regulations and practices. Subject to the provisosin subparagraphs (a) and (b), canopy claddingshould have a surface spread of flamecharacteristic not inferior to Class 1 of BS 476Part 7.

(a) Canopy facias should have a surface spreadof flame characteristic not inferior to Class 3of BS 476 Part 7. The edges of allplastic/acrylic materials should be protectedby steel or aluminium;

(b) Lighting units may be installed undercanopies provided that they do not exceed10% of the canopy area and are placed toprevent flame spread from one to another.Diffusers for the units should have a surfacespread of flame characteristic not inferior toClass 3 of BS 476 Part 7.

86 Where canopy stanchions are part of orclose to metering pumps and dispensers, anycladding should have a surface spread of flamecharacteristic not inferior to Class 2 of BS 476Part 7. Pole and price signs should stand apartfrom the canopy and, unless their proximity to aroad tanker delivery stand makes a higher

standard necessary, should have a minimum ofClass 3 surface spread of flame.

87 Lighting boxes installed over meteringpumps and dispensers should be small, isolated

from the metering pumps/dispensers andpositioned to prevent flame spread from one toanother. They should have a surface spread offlame characteristic not inferior to Class 3 ofBS 476 Part 7 and any exposed edges should beprotected by steel or aluminium.

Marking and identifhation of tanks andassociated equipment

88 The purpose of marking and identification isto avoid confusion or errors which might lead to anincident. All markings and identifications should beclear, durable, not readily altered or obliterated(taking into account chemical corrosion), and inpositions where they can be easily read. Paper orcardboard labels should not be used.

89 Each tank should be marked with anidentifying number to distinguish it from any othertank. In the case of multi-compartment tanks, eachcompartment should be marked with a separatenumber and type of fuel. Each dipstick or othermeasuring device should be marked to beidentifiable with its associated tank or compartment.

90 Each direct filling or off-set filling pipe shouldalso be marked to be identifiable with itsassociated tank or compartment and to show thetype of fuel which its associated tank orcompartment is used for. The marking should beas close as possible to the connection for thedelivery hose from a road tanker. All valves inpipework should be marked similarly and anyabove-ground pipework should be colour-coded.

Fire and emergency equipment

91 The possibility of fires or other incidents atfilling stations is minimised by careful site planningand design, sound construction and installation oftanks and other equipment, and good operatingpractices. Nevertheless, fires and petrol spills orleaks may occur. Adequate means for summoningthe local fire brigade and suitable equipment forcontrolling minor incidents and for limiting theescalation of incidents should be installed.

92 At attended self-service and attendantoperated filling stations, a telephone should beinstalled close to any control point or attendantskiosk. In addition, the following devices should be

installed.

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(4

(b)

Cc)

(4

At a location readily accessible for quickoperation by an attendant at the control point

- an emergency switch for switching off allmetering pump/dispensing equipment andintegral lighting with an adjacent warningnotice (eg PETROL PUMPS. SWITCH OFFHERE);

On the forecourt readily accessible tofirefighters and members of the public - anemergency switch which will isolate allmetering pumps/dispensing equipment andintegral lighting with an adjacent warningnotice as above;

At a location accessible to firefighters calledto deal with an emergency - a switch fordisconnecting neon and/or high voltagesigns with an adjacent warning notice(ie HIGH VOLTAGE SIGN. FIREMANSSWITCH);

At attended self-service filling stations - aloudspeaker system for communicating withcustomers.

Upto 2For up to each additional 2 1 more

Further guidance on isolation and switching isgiven in paras 201 to 212; and on loudspeakersystems in para 194.93 At unattended self-service filling stations, anemergency cabinet should be installed on theforecourt to be readily accessible to customers.The cabinet should be conspicuous and shouldhouse a telephone, fire extinguishers and anemergency switch interlocked with the door of thecabinet to isolate the metering pumps when thedoor is opened (see also para 210). A switchshould also be installed as described in paragraph92(c). In addition, the following emergency warningnotices should be installed at or close to:

Notes

1 Extinguishers should not have fire ratings of less than

348in tests shown in BS 5423.2 All extinguishers at a filling station should be compatible

and of the same method of operation. BS 5423 and BS 5306

Part 3 are appropriate.

Warning and information notices

General

(a) the telephone - a notice displaying the nameand address of the filling station and of theperson to be contacted in case ofemergency;

(b) dispensing points - notices displaying theactions to be taken in the event of a fire orother emergency.

All notices should be conspicuous, should beilluminated where necessary and may be pictorialor may include pictorial symbols, if appropriate.Guidance on specifications for notices is given inpara 95.

95 The use of conspicuous and easilyunderstood notices can help the safety ofoperations at filling stations and the effective actionnecessary in the event of a fire or other

emergency. There are therefore clear advantagesin following the BS safety signs and colours systemfor all notices, whether or not they are or theyinclude pictorial symbols. For certain types of signsin some circumstances, the Safety SignsRegulations 1980 require that system to befollowed (see para 18(a)). In all othercircumstances, the system (including the fire safetysigns system) in BS 5378 and BS 5499 should befollowed when selecting signs to carry theinformation in paras 69, 92, 93 and 96.Notices for customers and other visitors

94 At all filling stations a supply of dry sand or 96 At all filling stations, in addition to the noticessimilar absorbent material should be kept in a described in paras 69, 92 and 93, notices

container with a close fitting lid and should beinstalled in an accessible place. The means for

applying the material should also be provided. Thesupply should be sufficient to clean up small spillsor leaks of petrol (eg 1 full bucket for each fireextinguisher installed). Other fire and emergencyequipment, including any fire extinguishers whichmay be necessary for kiosks and other smallbuildings associated with the forecourt, should beinstalled in accordance with advice from the localfire brigade. As a general glide, the,minimumequipment necessary for the forecourt consists offoam fire extinguishers of not less than 9 litrescapacity each or dry powder extinguishers of notless than 4.5kg capacity each according to thescale in, and notes below, Table 6.

Table 6 Fire extinguishers

Metering pumps or

dispensers

Extinguishers (see Notes below)

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displaying the words PETROL (or PETROLEUMSPIRIT), HIGHLY FLAMMABLE, NO SMOKINGand SWITCH OFF ENGINE should be installed inthe vicinity of metering pumps or dispensers. Theyshould be positioned so that the warnings andinstructions are brought to the attention ofcustomers immediately on their arrival at thedispensing equipment. Similar notices should alsobe installed close to tank filling points.

compartment should be pressurised up to 0.5 bargand sealed, temperature and atmospheric readingsshould be taken and the tank or compartment left forthe period of test as set out in Table 7. There shouldbe no pressure loss during the period of test.

Table 7 Period of pressure test

Notices for filling station employees

Nominal capacity of tank or Period of test

compartment not exceeding I \

97 The Petroleum (Consolidation) Act 1928,Section 2(4), requires an occupier of a fillingstation to display a notice setting out any

conditions of licence to be observed by personsemployed at the filling station (see para 8). Thenotice should be installed where it is readilyaccessible and easily readable by all employeeslikely to be at the filling station at any time.

15,000 litres

30,000 litres

45,000 litres

60,000 litres

24 hours

48hours

72hours

96 hours

Testing, commissioning and record

keeping

(Note: When a multi-compartment tank is tested, pressure

should be applied so that the maximum differential pressurebetween adjacent compartments does not exceed 0.14 barg.

Care should be taken to ensure there is no overpressurisation

of compartment plates).

Testing of all tanks

98 Each underground tank should be examined

visually before installation and tested forsoundness by a competent person after loweringinto the excavation but before concreting or infillingtakes place. The purpose of the visual examinationis to check that any corrosion protection applied tothe exterior of a tank is undamaged and that thetank is securely settled on a level base. Thepurpose of the test is to ensure that the tank or anycompartments remain sound under pressures atleast as great as those they must sustain duringnormal service. The competent person shouldcertify his satisfaction with the examination andtest. Notice of the examination and test should begiven to the licensing authority so that an officer

may agree a time and date for visiting, ifnecessary.

101 In the case of GRP tanks, the guidance inparas 99 and 100 should be followed. Precautionsshould be taken to ensure that any tanks leftuncovered after testing are not damaged byvehicles or other work activities. In cases of doubt

about the integrity of tanks left uncovered for aperiod, retesting should be undertaken before thetanks are finally covered.

102 Guidance on safety in pressure testing inHSE Guidance Note GS4 should be followed. Theguidance stresses the dangers of all pressuretesting and sets out specific safety precautions.

Testing of pipelines and fittings

103 All joints in pipelines should be tested forsoundness and checked for signs of leaks by acompetent person before underground pipe runs

are encased in concrete or otherwise buried. Priornotice to the licensing authority and certification ofsatisfaction should be given (see para 98).

99 Generally, hydrostatic testing according tothe following method should be used for steeltanks. Each tank or compartment should be filledwith water to just below the neck of the manholecollar. Additional pressure of 0.5 barg should beapplied by means of air and the pressuremaintained for one hour. There should be noobservable leaks.

104 All non-pressure lines (ie suction, off-setfilling and vent pipes) should be subjected to airpressure of 0.7 barg. While under that pressure,each joint should be wiped with soapy water andchecked for signs of leaks. The soapy water shouldbe applied over the surfaces of all elbows andsimilar fittings.

100 Alternatively, in exceptional circumstances 105 All pressure lines (ie pipelines between

where the possibility of hydrostatic testing as remote or submerged pumps and dispensingdescribed above is excluded, a pneumatic test equipment) should be hydrostatically pressurewithout water may be used, as follows. The tank or tested at 111~ times their normal working pressures

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and examined for leaks. Alternatively, provided thatguidance on safety in pressure testing in HSE

Guidance Note GS4 is followed, an air pressuretest may be used over a period based on 2minutes for every 5 litres capacity of the line,subject to a minimum of 15 minutes. During thetest, soapy water should be used to detect leaks(see para 104).Metering pumps, dispensers and associatedpumping equipment

106 All metering pumps, dispensers andpumping units, together with associated valves,should be checked for leaks after installation by acompetent person. Hoses and nozzles and theirconnections should also be checked. Furtherguidance is included in BS 7117 Parts 1 and 2.

Commissioning

107 Before the filling station is brought intooperation, it should be inspected by the licensee orother competent person to ensure that its conditionis safe for public access and use. In particular, theinspection should ensure that:

para 10). The licensing authority is unlikely to granta licence until items (a)-(h) ofpara 107 have beensatisfied.

Record keeping

109 Paragraph 166 points out that themanagement of safety at a filling station will benefitfrom the maintenance of clear records of variousactivities which affect safety. A specimen registerfor keeping the records sequentially is included atAppendix 1. Such records are best started with theagreed site plan including final pipeline routes (seeparas 31 and 33), the results of initial tests andinspections of tanks, pipelines, metering pumpsand dispensers (see paras 98, 103 and 106) andthe results of the commissioning inspection (seepara 107).

(a) (b)

(4

(4(e)(f)(9)

(h)

all initial tests of tanks, pipelines and fittingshave been carried out and certified;

the initial inspection and tests of theelectrical installation have been carried outand certified (see Part 3);

the site is clear of combustible material,including weeds and long grass, contractorsplant and equipment;

all emergency equipment has been installedand is in working order;

all warnings and information notices are inplace;

all necessary means of escape are provided;

all marking and identification of tanks andassociated equipment have been carried outaccurately;

all drainage and interceptors are installedand connected.

Appropriate records should be completed (seepara 109 and Appendix 1).108 Before petrol is brought onto the fillingstation, its keeping should be authorised by alicence issued by the licensing authority (see

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Part 2 Operations and maintenance

General operations 32Responsibility for safety 32Relationship with the licensing authority 32Precautions against fires, explosions, leaks and spills 32

Dispensing activities 33General 33

Attendant operated filling stations 33Attended self-service filling stations 33Unattended self-service filling stations 33Commercial filling stations 34

Storage activities 34

Road tanker deliveries 34Storage of diesel fuel In multi-compartment petrol tanks 34Monitoring and testing for leaks 34Continuous inventory checking 34Leak testing 35

Maintenance, repairs and modifications 35General 35Cleaning of tanks 36Repair of tanks 36Modification of tanks 36Tanks taken out of use temporarily 36Tanks taken out of use permanently 37

Disposal of tanks 37Modification, repair and removal of pipelines 38

Operating and emergency procedures 38

Training 38

Record keeping 38

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General operations

Responsibility for safety

110 Overall responsibility for the safety ofoperations at any filling station rests with thelicensee. Arrangements for keeping anddispensing petrol authorised by the licensingauthority at the time of the issue of the licenceshould be adhered to; conditions attached to thelicence should be met; all reasonable steps toprevent fires, explosions and leaks or spills ofpetrol should be taken; clearly defined operatingand emergency procedures should be brought tothe attention of all persons involved; and adequatetraining for persons employed should be provided.

A responsibility for the safety of operations alsorests with persons employed during the times theyare involved with the running of the filling station.

Relationship with the licensing authority

111 Arrangements authorised by the licensingauthority when the licence is issued commonlycover matters such as the total quantity of petrolwhich may be kept, the locations and sizes oftanks, the configuration and number of meteringpumps or dispensers, the mode of operation of thefilling station (eg attended self-service operation),

the locations of road tanker delivery stands and thenatures and locations of buildings or otherstructures. Any proposals to vary the authorisedarrangements should be submitted to the licensingauthority; work should not start until the licensingauthority has agreed to it in writing. Anyinformation about developments adjacent to thefilling station which might affect the safety ofoperations should be passed to the licensingauthority.

112 The licensing authority should also be givennotice of:

(a )

(b)

Cc)(4

any fire, explosion, spillage or other incidentinvolving petrol and any leak or suspectedleak of petrol, as soon as possible after theevent;

any proposal to discontinue the use of anystorage tank or compartment;

any proposal to repair, modify or remove astorage tank or compartment or pipeline;

any intention to transfer the occupancy of thefilling station to another person.

Precautions against fires, explosions, leaksand spills

113 As far as possible, all sources of ignitionshould be excluded from hazardous areas (seeparas 23 to 26). Likely sources of ignition includesmoking, smoking materials and other nakedflames; any tools or other equipment which maycause sparks if rubbed, knocked or chippedagainst metal, concrete or brick; hot surfaces; andfixed or portable electrical equipme,nt notspecifically designed for use in hazardous areas(see Part 3).

114 Appropriate steps should be taken to preventleaks and spills of petrol and to detect the sources

of any leaks, including leaks suspected becauseof, for example, evidence from monitoring petrolstocks and use (see paras 135 to 138) orexcessive petrol odours at or in the vicinity of thefilling station. Any leaks or spills should beprevented from escaping from the filling station.Small leaks or spills should be cleared up promptlyby the application of dry sand or other absorbentmaterial.

115 All sand or other material used for clearing orcontaining leaks or spills should not be exposed toa source of ignition and should be disposed ofsafely (eg by removal from the fil!ing station by ahazardous waste disposal specialist). If it isretained for any length of time pending disposal, itshould be kept in a safe place (eg in a closed binor other co

Petrol Filling Stations- Construction and Operation_2

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