CODE OF PRACTICE 41 CP 41 - Rev 2 - For... · 2018. 10. 23. · 11. FUEL QUALITY 61 11.1 Proton...
Transcript of CODE OF PRACTICE 41 CP 41 - Rev 2 - For... · 2018. 10. 23. · 11. FUEL QUALITY 61 11.1 Proton...
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CODE OF PRACTICE 41
THE DESIGN, CONSTRUCTION,
MAINTENANCE AND OPERATION OF
FILLING STATIONS DISPENSING
GASEOUS FUELS
REVISION 2: 2018
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1 BCGA 41 – Revision 2
CODE OF PRACTICE 41
THE DESIGN, CONSTRUCTION, MAINTENANCE
AND OPERATION OF FILLING STATIONS
DISPENSING GASEOUS FUELS
REVISION 2: 2018
Copyright © 2018 by British Compressed Gases
Association. First printed 2014. All rights reserved. No
part of this publication may be reproduced or transmitted in
any form or by any means, electronic or mechanical,
including photocopy, without permission from the
publisher:
BRITISH COMPRESSED GASES ASSOCIATION Registered office: 4a Mallard Way, Pride Park, Derby, UK. DE24 8GX
Company Number: 71798, England
Website:
www.bcga.co.uk
ISSN 2398-9440
http://www.bcga.co.uk/
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2 BCGA 41 – Revision 2
PREFACE
The British Compressed Gases Association (BCGA) was established in
l971, formed out of the British Acetylene Association, which existed
since l901. BCGA members include gas producers, suppliers of gas
handling equipment and users operating in the compressed gas field.
The main objectives of the Association are to further technology, to
enhance safe practice, and to prioritise environmental protection in the
supply and use of industrial, food and medical gases, and we produce a
host of publications to this end. BCGA also provides advice and makes
representations on behalf of its Members to regulatory bodies, including
the UK Government.
Policy is determined by a Council elected from Member Companies,
with detailed technical studies being undertaken by a Technical
Committee and its specialist Sub-Committees appointed for this
purpose.
BCGA makes strenuous efforts to ensure the accuracy and current
relevance of its publications, which are intended for use by technically
competent persons. However this does not remove the need for
technical and managerial judgement in practical situations. Nor do they
confer any immunity or exemption from relevant legal requirements,
including by-laws.
For the assistance of users, references are given, either in the text or
Appendices, to publications such as British, European and International
Standards and Codes of Practice, and current legislation that may be
applicable but no representation or warranty can be given that these
references are complete or current.
BCGA publications are reviewed, and revised if necessary, at five-
yearly intervals, or sooner where the need is recognised. Readers are
advised to check the Association’s website to ensure that the copy in
their possession is the current version.
This document has been prepared by BCGA Technical Sub-
Committee 9. This document replaces BCGA Code of Practice 41,
Revision 1: 2016. It was approved for publication at BCGA Technical
Committee 159. This document was first published on 23/10/2018.
For comments on this document contact the Association via the
website www.bcga.co.uk.
http://www.bcga.co.uk/
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CONTENTS
Section Page
TERMINOLOGY AND DEFINITIONS 6
1. INTRODUCTION 12
2. SCOPE 16
3. RISK MANAGEMENT 19
3.1 General 19
3.2 Principle legal requirements 19
3.3 Environmental risk assessments 20
4. PRE-DESIGN 21
5. PLANNING PERMISSION AND PERMITS 22
5.1 General 22
5.2 Storage 22
5.3 Multi-fuel stations 23
6. LAYOUT AND SITE SELECTION CRITERIA 23
6.1 General 23
6.2 Location of storage installation 24
6.3 Access and egress for fuel delivery vehicles 28
6.4 Location and installation of dispensing points 30
6.5 Connecting pipework 31
6.6 On-site fuel generation equipment and related process
equipment.
32
6.7 Vent systems 32
6.8 Vent recovery 32
6.9 Other filling station activities 33
7. DESIGN OF FILLING STATION 33
7.1 General 33
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7.2 Fuel gas storage and process equipment 40
7.3 LNG vaporiser 43
7.4 Fuel delivery 44
7.5 Connecting pipework and valves 44
7.6 Dispensing equipment 45
7.7 Venting and vent stacks 49
7.8 Dispenser plinth earthing and grounding 50
7.9 Canopy 50
7.10 Gas fuels on multi-fuel stations 50
8. INSTALLATION AND COMMISIONING 50
8.1 Installation 50
8.2 Pre-commissioning 50
8.3 Commissioning 53
8.4 Handover for operation 54
8.5 End of life 56
9. OPERATION 56
9.1 Delivery 56
9.2 Vehicle filling – Fuel dispense 57
10. PERIODIC EXAMINATION & MAINTENANCE 59
11. FUEL QUALITY 61
11.1 Proton Exchange Membrane hydrogen 62
11.2 Non-Proton Exchange Membrane hydrogen 63
11.3 CNG and LNG 63
12. COMPETENCE OF PERSONNEL INCLUDING TRAINING 64
13. PERSONNAL PROTECTIVE EQUIPMENT 68
13.1 Public access filling 68
13.2 Non-public access filling 68
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13.3 Maintenance and fuel delivery 68
14. EMERGENCY SITUATIONS AND PROCEDURES 68
15. SECURITY 70
16. REFERENCES * 71
APPENDICES:
APPENDIX 1 Minimum recommended separation distances for hydrogen
storage installations
81
APPENDIX 2 Minimum recommended separation distances for natural
gas storage installations
82
APPENDIX 3 Hydrogen - General data and safety considerations 83
APPENDIX 4 Natural gas - General data and safety considerations 85
APPENDIX 5 Checklist for approval to install and operate filling stations 87
APPENDIX 6 Checklist for emergency services 88
* Throughout this document numbers in brackets refer to references in Section 16. Documents
referenced are the edition current at the time of publication of this Code of Practice, unless
otherwise stated.
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TERMINOLOGY AND DEFINITIONS
Assembly A number of parts or combination thereof that are joined together to
perform a specific function and subject to disassembly without
degradation of any of the parts, e.g. a hose assembly combining a
nozzle, hose set and breakaway coupling.
Biomethane Biomethane is upgraded Biogas, a natural occurring gas with similar
properties to natural gas, produced by the anaerobic digestion of
waste such as organic matter, food waste, sewage, landfill etc. It
can be stored in two forms, compressed (CBG) or liquefied (LBG).
Boil-off gas Gas emissions caused by the evaporation of a liquefied gas in
storage tanks and other parts of the station.
Break-away device A device that stops the flow of gas allowing safe disconnection from
the fuelling system in the event of accidental disconnection, i.e. a
vehicle drive-away when the hose is still connected.
Bulk storage For the purposes of this document bulk storage is defined as fuel gas
storage which consists of either:
fixed gas cylinders manifolded together; or
tubes which may be either fixed in place or mounted on a transportable trailer; or
one or more liquefied gas vessels.
Bundle Assembly of cylinders that are fastened together and which are
interconnected by a manifold and transported as a unit, having a total
water capacity not exceeding 3000 litres.
Bund A containment structure typically made of concrete that diverts a
liquefied gas to a safe area for dissipation into the atmosphere.
Canopy A roof, overhead shelter, or hood providing the station or fuel
dispenser with a degree of weather protection.
Competence The employer is responsible for ensuring that employees are
competent to carry out each task safely and correctly. For
additional information on competence refer to BCGA GN 23 (97),
Gas safety. Information, instruction and training.
There are specific roles, such as a ‘Competent Person’, which are
defined in legislation, for example, the Pressure System Safety
Regulations (11).
Compressed
natural gas
Compressed natural gas (CNG), including methane and biomethane.
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Control point A position in a kiosk or other building at an attended self-service
filling station from which an attendant can view and supervise
activities at the dispenser, activate the equipment, and shut-off the
dispenser, in the case of emergency.
Cryogenic Cryogenic liquids are liquefied gases that are kept in their liquid
state at very low temperatures, typically lower than -150 °C.
Cylinder Transportable pressure receptacle of a water capacity not exceeding
150 litres.
Dead man’s button
/ switch
A device that automatically shuts down an operation in a safe
manner, i.e. when refuelling a vehicle or during a fuel transfer.
Automatically operated if the operator releases pressure on the
button/switch.
Deflagration A rapid chemical reaction in which the output of heat is sufficient to
enable the reaction to proceed and be accelerated without input of
heat from another source. Deflagration is a surface phenomenon
with the reaction products flowing away from the unreacted material
normal to the surface at subsonic velocity. The effect of a
deflagration under confinement is an explosion. Confinement of the
reaction increases pressure rate of reaction and temperature and may
cause transition into a detonation.
Detonation An exothermic reaction wave which follows, and also maintains, a
supersonic shock front from an explosion. Such transitions are
promoted by the increased turbulence arising from a deflagration
flame front interacting with strong structures.
Dispenser Pump or equipment used to dispense fuel at a filling station.
Docking station A docking station is a housing, pad or post where the dispenser
nozzle is stored to prevent damage, ingress of dirt, or moisture. A
docking station for an LNG nozzle may be heated to prevent the
build up of ice and condensation.
Dry air Air with a maximum dew point of -40 ºC.
Embrittlement Embrittlement is a loss of ductility of a material making it brittle.
Embrittlement of some carbon steels may be caused as a result of
exposure to low temperature gases, for example, from a liquefied
gas. Hydrogen embrittlement is the effect of hydrogen absorption
on some metals and alloys. The degradation of a structural material
may result in failure or a leak.
Explosion A nuclear, chemical or physical process leading to the sudden
release of energy (and usually gases and heat) giving rise to external
pressure waves.
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Equipment supplier
/ installer
The company or companies, as contracted by the Owner / User, to
provide and install the equipment used to store, distribute and
dispense a specific fuel gas.
Fast-fill For natural gas, a filling operation that takes a similar amount of
time as current liquid fuels to fill.
Filling station A facility for the storage and dispensing, normally to the general
public, of products used as fuels for motor vehicles. These can
include petrol, diesel, autogas (LPG), hydrogen, CNG, LNG and
LCNG.
NOTE: Hydrogen filling stations may typically be referred to as
Hydrogen Refuelling Stations (HRS), however the term filling
station is used for consistency with other UK documents concerning
petrol, diesel and LPG filling stations.
Flammable gas Gases which at 20 °C and at standard atmospheric pressure:
(i) are ignitable when in a mixture of 13 % or less by volume with air; or
(ii) have a flammable range with air of at least 12 percentage points regardless of the lower flammability limit.
Forecourt attendant Responsible to the Site Operator. Directly operates and controls
the dispenser and the discharge nozzle on behalf of the customer.
Gas supplier The company contracted by the Owner / User to provide a specific
fuel gas product for dispense at the filling station.
Gaseous storage A system which includes containers, pressure regulators,
instruments, safety-relief devices, manifolds, inter-connecting
piping and controls. The storage system terminates at the point
where the gas enters the distribution piping.
Hazardous area Any place in which an explosive atmosphere may occur in quantities
such as to require special precautions to prevent ignition during
construction, installation or use, as applicable.
Heavy goods
vehicle
Heavy Goods Vehicle (HGV) (also known as LGV, Large Goods
Vehicle). Commercial truck with a gross combination mass of more
than 3500 kg.
Installation Equipment (vessels, pumps, compressors, electrolysers, reformers
etc.), pipework, hoses, valves, instruments etc. that have been
assembled into one or more systems that enable the generation,
storage or dispensing of gaseous fuels.
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Invacuation A variant of the commonly understood concept of evacuation (for
example, in the event of a fire). Invacuation involves the removal
of people to an alternative area within the site.
Leakage See Methane Leakage
Liquefied
Compressed
Natural Gas
(LCNG)
LNG warmed and vaporised to product CNG for dispensing
Liquefied natural
gas
Liquefied natural gas (LNG), including methane and biomethane
(LBG).
LNG Vaporiser A heat exchanger used for regasifying liquefied gases.
LPG Liquefied petroleum gas
Maintenance staff Typically employed by the equipment supplier / installer, or the
gas supplier. Has significant understanding of the design and
operational elements of both the gas dispensing and storage /
generation equipment, as appropriate.
May An option available to the user of this Code of Practice.
Methane leakage The loss, emission of methane due to leakage, venting, coupling
losses, for example, of the storage system. This concept is distinct
from that of ‘methane slip’, which concerns poor combustion
(combustion efficiency) i.e. in a vehicle using an internal
combustion engine. Methane leakage has an undesirable
environmental and safety impact.
Mobile station A fueling station that can be transported with product onboard.
Mobile workers Persons who work in more than one place or travel as part of their
job, i.e. HGV and public service vehicle drivers.
Multi-fuel
dispenser
Dispenser delivering multiple fuels, liquid or gaseous.
Non-hazardous area Any place in which an explosive atmosphere is not expected to
occur in quantities such as to require special precautions to prevent
ignition during construction, installation and use.
Odorization The process of adding an odorant to gas in order that it can be
detected by smell.
Owner / user The owner of a filling station. Within this Code of Practice the
owner has the same responsibilities as the user, as defined in the
Pressure Systems Safety Regulations (11).
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Public service
vehicle
Public service vehicle. A vehicle such as a bus used by members
of the public to travel to and from places on particular routes.
Self-service
attendant
Responsible to the site operator. Supervises customers operating
dispensers, with the responsibility to activate or, in the case of
emergency, shut-off the dispenser from a defined control point.
Separation
distances
Horizontal and vertical distances between the nearest part of the
gas storage and distribution system and any specified feature (for
example, occupied buildings, facilities, process areas, site
boundary). The purpose of a separation distance is to protect the
gas storage and distribution system from heat radiation should
there be a fire in the local area, also to protect the local area from
the effects of a fuel gas release. The intention is to provide
sufficient time for emergency evacuation as appropriate and the
mobilisation of additional fire-fighting equipment.
NOTE: The term separation distance should not be confused with
the distances involved with hazardous area classification.
Shall Indicates a mandatory requirement for compliance with this Code
of Practice and may also indicate a mandatory requirement within
UK law.
Should Identifies a preferred, but not mandatory requirement for
compliance with this Code of Practice.
Site operator Responsible to the owner / user. Person (or company) in charge of
(with day to day control) a filling station i.e. the petroleum spirit
licence holder. In some cases this will be the owner.
Slow-fill For natural gas, a slow (or timed) filling operation that takes a
longer amount of time than current liquid fuels to fill, and can take
several hours.
Tanker stand The position on a filling station where a fuel delivery tanker is
located during the fuel delivery process.
Tube A transportable pressure receptacle of seamless or composite
construction having a water capacity exceeding 150 litres and of not
more than 3000 litres.
NOTE: Tube design is evolving and it is possible to obtain tubes
with a water capacity greater than 3000 litres, but these do not
comply with the current transport Regulations which define a tube.
Unattended self-
service
A filling station where the dispenser is activated and operated by a
customer without supervision by an attendant.
Venting Controlled and uncontrolled release of gas into the atmosphere.
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Vapour recovery
equipment
Recovers boil-off gas to prevent it from escaping into the
atmosphere. Equipment may include a receiver, ambient vaporiser,
compressor and buffer storage, enabling recovered gas to be
dispensed as CNG. It may also consist of an assembly for re-
liquefying boil-off gas from the vehicle fuel tank or road tanker,
which is returned as LNG to the station storage vessel.
Vulnerable
populations
Vulnerable populations include those who may not be easy to
evacuate from premises because of, for example, age or infirmity,
including schools, hospitals, old people’s homes and other
residential accommodation.
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CODE OF PRACTICE 41
THE DESIGN, CONSTRUCTION, MAINTENANCE AND OPERATION
OF FILLING STATIONS DISPENSING GASEOUS FUELS
1. INTRODUCTION
Globally there is a growing awareness of the environmental concerns around the use of
traditional fuels. Low, or zero emissions from exhausts and a reduced carbon footprint are
part of the future. The use of alternative fuels for vehicles is becoming more widespread in
the UK. The use of liquefied petroleum gas (LPG) is well established and the technical and
safety requirements for other gaseous fuels are being developed. All fuels are subject to UK
legislation or guidance.
Alternative gaseous fuels have a part to play in reducing UK carbon emissions, as recognised
in the European Commission Clean Power for Transport package of measures, which aims to
ensure the build-up of alternative fuel stations across Europe together with common standards
for their design and use. This package includes a European alternative fuels strategy,
European Communication 2013/17/EC (31), and a Directive on the deployment of a
European alternative fuels infrastructure, European Directive 2014/94/EU (35). To
implement this Directive the UK has enacted the Alternative Fuels Infrastructure Regulations
(23).
A number of international standards, national standards and industry documents from other
countries relating to the design and operation of alternative fuel vehicle filling stations have
been published, or are currently in the process of being developed.
The British Compressed Gases Association (BCGA) recognises that the alternative gaseous
fuels industry is still developing and this document signposts the important points of multiple
guidance documents.
The BCGA acknowledges that there are discrepancies between several of these documents
and that there will inevitably be revisions required in future. However, given the legally-
binding UK national requirement to reduce carbon emissions, the BCGA has taken the
decision to publish this signpost document to facilitate the timely development of alternative
gaseous filling station infrastructure.
The BCGA seeks to provide with this Code of Practice a minimum industry standard to
ensure a consistent high level of safety and to provide a reference document for those
involved in the design, planning, operation and regulatory approval of alternative gaseous
fuel stations.
The BCGA will review this document at intervals to continually reflect the experience of this
growing industry and welcomes suggestions from interested parties.
This code of practice is intended to outline the major technical and safety considerations
required in the UK during the design, construction, maintenance and operation of vehicle
filling stations which incorporate filling facilities for liquefied natural gas (LNG),
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compressed natural gas (CNG) and hydrogen (H2), drawn from existing BCGA publications
and other major documents in order to comply with more general safety regulations and to
ensure safe operation.
For more traditional vehicle fuels such as petrol, diesel and LPG , the primary publication for
the requirements of the design, construction, modification, maintenance and
decommissioning of filling stations, published by the Association for Petroleum and
Explosives Administration (APEA) and Energy Institute (EI), is the Design, construction,
modification, maintenance and decommissioning of filling stations (the Blue Book) (103). It
has been produced jointly by the APEA and the EI with input from the Health and Safety
Executive (HSE) and other industry stakeholders.
This code of practice is designed to be complementary to the Blue Book (103). Where
gaseous fuels and traditional fuels are dispensed at the same filling station, due regard should
be taken of both this code of practice and the Blue Book (103). Specific guidance for
dispensing hydrogen alongside traditional vehicle fuels is available in a supplement to the
Blue Book (103), Guidance on hydrogen delivery systems for refuelling of motor vehicles co-
located with petrol fuelling stations (104), which has been jointly developed by the EI, APEA
and BCGA.
There are differences between the various gaseous fuels covered by this code of practice and
these should be taken into account.
Whilst both CNG and gaseous hydrogen are typically stored at high pressure, the pressures
involved in hydrogen vehicle filling are likely to be considerably higher than those involved
with CNG vehicle filling. The risk of harm / damage to the surroundings due to leakage from
the installation should therefore take into consideration the storage and operational pressures
of the gas, and may require more extensive safeguards for high pressure hydrogen systems.
In addition, the security of the storage and delivery areas shall be assessed. It is likely
however that both CNG and hydrogen fuel installations will have the same risk of damage by
3rd parties etc. Thus civil engineering protection of both types of filling stations is similar.
The principle hazards associated with hydrogen are:
Flammability;
Asphyxiation;
Material embrittlement and subsequent mechanical failure;
Increased likelihood of leakage from joints, due to smaller molecular size and where applicable, higher pressures;
Undetected leaks due to lack of odour;
Undetected fire due to invisible flame;
Increased likelihood of ignition of a leak;
For liquid hydrogen, cold burns when exposed to the skin;
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Increased risk of injury as a result of uncontrolled release of high pressure gas;
Potential transition of an explosion from deflagration to detonation.
CNG and LNG are relatively new road fuels in the UK. Although natural gas as an energy
source for domestic households, commercial property and industry is well accepted, there are
major differences that have to be observed when using natural gas as a road fuel.
CNG is natural gas that has been compressed to a high pressure, typically 200 to 300 bar (20
to 30 MPa) in order that large volumes of energy can be stored, enabling it to be used in
vehicles as a replacement or substitute to current liquid fuels. The high-pressure gas can be
stored in steel or composite cylinders of various diameters and lengths.
The principle hazards associated with CNG are as follows:
Flammability;
Asphyxiation;
Undetected leaks due to lack of odour, where applicable;
Undetected fire due to difficult to see flame. CNG has a blue flame, which under certain light conditions may be hard to see.
Increased risk of injury as a result of uncontrolled release of high-pressure gas.
LNG is natural gas in a liquid form, as a cryogenic it is cooled to approximately -162 ºC. It is
mainly used as an energy source for heavy-duty road transport and can be converted back
into a gaseous state when delivered to a cryogenic storage vessel and warmed to ambient
temperature.
The principle hazards associated with LNG are as follows:
Flammability;
Asphyxiation;
Cold burns when exposed to the skin;
Undetected leaks due to lack of odour;
Undetected fire due to difficult to see flame;
Material low-temperature embrittlement and subsequent mechanical failure (to mild and carbon steels);
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If LNG is released it flashes. The vapours are initially heavier than air and will form a gas cloud close to the ground, which will eventually dissipate. However, under
specific conditions, where a vapour cloud exists with LNG between its lower and
higher flammability limits in air (5 % to 15 %), if a source of ignition is present the
vapour cloud could ignite, and this may be some distance from the actual release
source. Vapour clouds also introduce hazards from the visual impairment they create.
Other specific considerations are outlined in Appendix 4.
Some of the important international reference documents addressing the design and operation
of hydrogen vehicle filling stations include:
ISO/TS 20100 (64), Gaseous hydrogen. Fuelling stations. (Document withdrawn, reference only).
ISO/TS 19880 (63), Gaseous hydrogen. Fuelling stations. Part 1. General requirements.
USA - NFPA 2 (109), Hydrogen technologies code.
Germany - VdTÜV MB DRGA 514 (113), Requirements for hydrogen fuelling stations, Compressed gases 514.
Some of the important international reference documents addressing the design and operation
of CNG vehicle filling stations include:
ISO 16923 (56), Natural gas fuelling stations. CNG stations for fuelling vehicles.
The Institute of Gas Engineers and Managers (IGEM) UP/20 (99), Natural gas fuelling stations.
USA - NFPA 52 (110), Vehicular natural gas fuel systems code.
Germany - G651/vdTUV M510 (112), Natural gas stations.
Netherlands – PGS 25 (114), Natural gas delivery systems for vehicles.
Israel - SI 6236 (116), Compressed natural gas (CNG) fuelling stations for vehicles.
Some of the important international reference documents addressing the design and operation
of LNG vehicle filling stations include:
ISO 16924 (57), Natural gas fuelling stations. LNG stations for fuelling vehicles.
IGEM/UP/21 (100), Liquefied natural gas fuelling stations. (Draft under development).
NFPA 52 (110).
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Netherlands – PGS 33 (115), Natural Gas. Liquefied natural gas (LNG) delivery installations for vehicles.
Other relevant documents that may be of interest to the reader are listed in Section 16.
This document is not a Design Code. The user of this Code of Practice shall make reference
where applicable to UK legislation and internationally recognised Standards where these
apply and should also take into account the specific practices of the UK industrial gases
companies.
All new installations or modifications to existing installations shall, as far as is reasonably
practicable, comply with this Code of Practice for the products or services involved.
This Code of Practice, along with the range of other BCGA publications, represents the
BCGA’s view of minimum requirements for safe practice.
2. SCOPE
This Code of Practice covers the location, design, installation, commissioning, operation,
maintenance and inspection of equipment used in a filling station for vehicle filling with
gaseous hydrogen, CNG, or LNG, with or without the dispensing of other vehicle fuels such
as petrol, diesel, liquefied petroleum gas (LPG) etc.
This document covers the delivery or on-site generation of the fuel (including compression as
appropriate), and equipment associated with storage and dispensing of the fuels included in
the scope. It includes guidance on emergency procedures, appropriate signage, and the
requirement for competent operating staff for the site, it also covers those carrying out filling
activities, which may include members of the public.
Storage of the fuel may be as a compressed or liquefied gas.
Recommendations of best practice are outlined to assist in compliance with UK regulations to
ensure the safety of the general public, and employees at a vehicle filling station:
BCGA Code of Practice (CP) 4 (91), Industrial gas cylinder manifolds and gas distribution pipework (excluding acetylene), covers the distribution of gases.
BCGA CP 33 (92), The bulk storage of gaseous hydrogen at users’ premises, covers storage and distribution of gaseous hydrogen in the UK.
BCGA CP 39 (93), In-service requirements of pressure equipment (gas storage and distribution systems).
BCGA CP 44 (94), The storage of gas cylinders, where gas cylinders are not connected.
BCGA CP 46 (95), The storage of cryogenic flammable fluids, covers the storage of liquid hydrogen and LNG in the UK.
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IGEM UP/20 (99) covers the supply of natural gas from the grid or mobile CNG storage, compression and dispensing of CNG to vehicles in the UK.
IGEM UP/21 (100) covers the supply of LNG from road tanker to storage and dispensing of LNG to vehicles and mobile stations in the UK.
NOTE: IGEM UP/21 (100) is still under development.
The relationship and interactions between these primary documents prepared to cover LNG,
CNG and hydrogen vehicle filling is shown in Figures 1 & 2. Where petrol is also dispensed
at the filling station, the requirements of the Blue Book (103 & 104) should be addressed.
Further reference appropriate to the use of flammable gases in the UK is made to:
European Industrial Gases Association (EIGA) Document 6 (82), Safety in storage, handling and distribution of liquid hydrogen.
EIGA Document 15 (83), Gaseous hydrogen stations, covers gaseous hydrogen, compression, purification, filling into containers and storage installations at consumer
sites.
BS EN 13645 (47), Installation and equipment for liquefied natural gas. Design of onshore installations with a storage capacity between 5t and 200t, in the primary
case.
In the absence of any other appropriate UK guidance for gaseous fuelled vehicle filling,
separation distances have been incorporated based on existing published guidance. It should
however be recognised that those currently included for compressed hydrogen, taken from
BCGA CP 4 (91) and BCGA CP 33 (92), are not necessarily intended for the pressures
encountered in a hydrogen vehicle filling station, which can be as high as 1000 bar. To allow
for this, where these distances are used, a reduced maximum internal pipe diameter of 8 mm
is recommended for hydrogen systems above 200 bar. For greater pipe diameters, it may be
appropriate to extend these distances. For systems operating at lower pressures, e.g.
production equipment, these separation distances may be conservative, and other methods of
determining the appropriate separation distances may be justifiable.
For potential leak points in the pipework and equipment involved in the dispensing of
gaseous hydrogen, isolated from the storage vessels outside of a filling activity, separation
distances taken from BCGA CP 4 (91) are recommended, again assuming a maximum
internal pipe diameter of 8 mm.
This Code of Practice does not include the requirements for a gaseous-fuelled vehicle, for
which up-to-date information should be sought from the Department for Transport (DfT). It
does not cover the general requirements of petroleum, diesel or liquid petroleum gas (LPG)
vehicle filling station, which are all adequately covered in other industry standard
publications. For information on LPG refer to the UKLPG Trade Association and their
document UKLPG CP 20 (117), Automotive LPG refuelling facilities.
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Figure 1. LNG and CNG
Figure 2: Hydrogen
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3. RISK MANAGEMENT
3.1 General The control of risks shall be managed throughout the lifetime of the filling station.
Suitable and sufficient risk assessments shall be conducted. Advice on carrying out
risk assessments is available on the BCGA website (www.bcga.co.uk – Gas Topics –
Risk Assessments).
3.2 Principle legal requirements
Health and Safety at Work etc. Act
Compliance with Health and Safety at Work etc. Act (1) and its subsidiary health and
safety legislation shall be maintained and should be demonstrable.
Management of Health and Safety at Work Regulations
The Management of Health and Safety at Work Regulations (10) contain general
requirements for employers and the self-employed to assess the risks to workers and
others (including the general public) who may be affected by their undertaking, so that
they can decide on what measures should be taken to comply with health and safety
law.
ATEX Directives / Dangerous Substances and Explosive Atmospheres Regulations
Areas in filling stations used for the production, storage and dispensing of flammable
gases are within the scope of the Dangerous Substances and Explosive Atmospheres
Regulations (DSEAR) (14) and will require a risk assessment, with classification into
appropriate hazardous areas, based on the anticipated size of a release of flammable
material and the degree of ventilation in each area.
Further guidance is available in HSE L138 (79), DSEAR. Approved code of practice
and guidance. Guidance on DSEAR (14) risk assessments is available in BCGA
Guidance Note (GN) 13 (96), DSEAR Risk Assessment.
In the UK the requirements of the ATEX Workplace Directive (25) were put into effect
through DSEAR (14). The requirements of the ATEX Equipment Directive (24) were
implemented by the Equipment and Protective Systems Intended for Use in Potentially
Explosive Atmospheres (EPS) Regulations (6). Compliance with DSEAR (14) and the
EPS Regulations (6) is sufficient to confirm compliance with these Directives.
NOTE: ATEX is the name commonly given to the two European Directives for
controlling explosive atmospheres. These are:
European Directive 99/92/EC (25) (also known as 'ATEX 137' or the 'ATEX Workplace Directive') on minimum requirements for improving the health
and safety protection of workers potentially at risk from explosive atmospheres.
European Directive 94/9/EC (24) (also known as 'ATEX 95' or 'the ATEX Equipment Directive') on the approximation of the laws of Members States
concerning equipment and protective systems intended for use in potentially
explosive atmospheres.
http://www.bcga.co.uk/
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20 BCGA 41 – Revision 2
All equipment installed in hazardous areas shall be appropriately certified according to
the ATEX Equipment Directive (24) for the type of hazardous area in which the
equipment is installed. On sites where multiple fuels are dispensed, consideration shall
be given to the properties and hazards of each fuel. This may require different ATEX
gas group classifications, for instance for hydrogen installations which due to the low
ignition energy of hydrogen, require equipment rated for gas group IIC hazardous
areas.
A document defining the hazardous areas associated with the plant and equipment
throughout the life cycle of the plant and the safety precautions that need to be taken
shall be created and kept up to date. This could take the form of a DSEAR (14) risk
assessment or an Explosion Protection Document, refer to the ATEX Workplace
Directive (25). Notably DSEAR (14) makes no mention an Explosion Protection
Document but the requirement for up to date information is very much a part of the UK
regulation and an Explosion Protection Document fits the need.
Where gaseous fuels and traditional fuels are dispensed at the same filling station,
specific guidance for the hazardous areas associated with petrol and diesel delivery,
storage, dispensing and service ducts and chambers etc. is available in the Blue Book
(103 & 104).
For specific information for natural gas installations refer to IGEM SR/25 (101),
Hazardous area classification of natural gas installations.
Provision and Use of Work Equipment Regulations
The Provision and Use of Work Equipment Regulations (PUWER) (9) requires that an
inspection and maintenance regime shall be in place to ensure the safety and suitability
of equipment on site. Refer to BCGA CP 39 (93).
Pressure Systems Safety Regulations
The Pressure Systems Safety Regulations (PSSR) (11) require a Written Scheme of
Examination to be drawn up or certified by a competent person. Examinations shall be
undertaken prior to use and thereafter in accordance to the Written Scheme of
Examination. For further information refer to HSE L122 (77), Safety of pressure
systems. PSSR 2000. Approved Code of Practice, and BCGA CP 39 (93).
Refer to Section 7, Design of filling station, for all other relevant legislation.
3.3 Environmental risk assessments
Risk assessments shall take into consideration the potential effect of gaseous fuels on
the environment.
Specific legislation requires environmental risks from dangerous, hazardous or
polluting substances to be assessed and controlled and it is therefore important that any
risk assessment is carried out not in isolation but as part of an overall assessment for a
site. Consideration may be required for potential cross-contamination of and
interaction between different products.
Where environmental risks dictate, for example, where fuel spillages may have an
impact, an effective incident response plan should be implemented.
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21 BCGA 41 – Revision 2
European Directive 2010/75/EU (28) on industrial emissions (integrated pollution
prevention and control) (IED), requires permits where a site is manufacturing
hydrogen. This is implemented in the UK through legislation such as the
Environmental Permitting (England and Wales) Regulations (22) and the Pollution
Prevention and Control (Scotland) Regulations (16).
4. PRE-DESIGN
The pre-design phase is a recommended important step in the station design and installation
process. The level of detail should be suitable to determine all relevant factors including
existing site conditions and refuelling requirements.
The pre-design assessment should consider:
Location - new or integration into existing;
Size and types of vehicles to be refuelled;
Retail or non-retail; public or private access;
Permanent or mobile facility;
Projected growth;
Fuelling behaviour and ergonomics (personnel and vehicles), access and egress, and vehicle traffic flow on site;
Fuel type(s);
Fuel quality;
Integration with existing fuels on site (e.g. in compliance with the Blue Book (103 & 104), etc.);
Number and type of dispensers to meet refuelling requirements, including any interoperability requirements, refer to the Alternative Fuels Infrastructure Regulations
(23);
Planning permission and permit control;
Quantity of fuel to be stored (consents and permitting), including compliance, as appropriate, with the Control of Major Accident Hazards Regulations (COMAH) (19);
Available space, boundary and separation distances;
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22 BCGA 41 – Revision 2
Available utilities (water, access to grid, electrical power);
Site conditions in relation to construction (wind loading, stability for vertical vessels or other equipment, seismic activity if applicable, flood risks, etc.);
Location of drains, manholes and culverts and other services including overhead and underground power lines;
Civil engineering;
Dedicated off-loading areas for incoming fuel deliveries, refer to BCGA CP 46 (95);
Tanker movements on site;
Site management, supervision and security.
5.0 PLANNING PERMISSION AND PERMITS
5.1 General
Responsibility for planning rests with the local planning authorities (in accordance with
the Town and Country Planning Act (2)). If planning permission is required, it should
be obtained before any work begins. The local fire authority should be involved at
planning stage.
Stability and ground evaluation, landscaping, height restrictions and grid connection
should all, where relevant, be taken into consideration.
Generation of hydrogen on site, (whether from steam methane reforming (SMR),
electrolysis or other sources), for commercial activities currently requires a permit
under the IED (28), refer to Section 3.3.
5.2 Storage
Depending on the quantity of stored fuel gas, refer to Table 1, consent may be required
from the Hazardous Substances Authority (HSA) in accordance with the Planning
(Hazardous Substances) Regulations (20) or the COMAH (19) Regulations. Under
COMAH (19), where sub-threshold quantities of dangerous substances are stored,
consideration should be given to the total quantity of products stored on a site
according to the aggregation rule, this will include petroleum, diesel, LPG and other
listed substances, in addition to any alternative vehicle fuels.
NOTE: The requirements of the EU Seveso III Directive 2012/18/EU (30) are
implemented by COMAH (19) in the UK.
In addition, the Dangerous Substances (Notification and Marking of Sites) Regulations
(NAMOS) (5) require notification to the authorities where a total quantity of hazardous
products of 25 tonnes or more are stored. Specific exemptions apply.
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23 BCGA 41 – Revision 2
Planning (Hazardous
Substances) Regulations
COMAH Regulations
Lower tier Upper tier
Hydrogen 2 tonnes 5 tonnes 50 tonnes
CNG 15 tonnes 50 tonnes 200 tonnes
LNG 15 tonnes 50 tonnes 200 tonnes
Table 1: Thresholds for the different fuel gases
5.3 Multi-fuel stations
The Petroleum (Consolidation) Regulations (17) require that anyone operating a petrol
filling and/or storage station shall have a storage certificate issued by their local
Petroleum Enforcement Authority (PEA). The PEA will usually require the installation
to meet the requirements of the Blue Book (103 & 104).
The requirement applies both to retail and non-retail filling stations i.e. those that
dispense petrol to the general public and those, which only dispense petrol into their
own vehicles. As part of the PEA assessment of a petrol filling station, prior to issuing
a storage certificate, the PEA will ensure that the arrangements for any other fuels
stored and dispensed on the site are also appropriate, and that the risks associated with
the fuels are controlled so as not to impact upon each other.
6. LAYOUT AND SITE SELECTION CRITERIA
6.1 General
Storage installations and production equipment shall be contained within secured areas.
Table 2 displays the typical components of an installation for various fuels.
The principle hazard from gaseous fuels is fire, but there may also be an environmental
hazard. Certain gases, such as methane or refrigerant gases, if released, are greenhouse
gases. Hydrogen does not generally have an environmental impact. Where there is an
impact on traditional fuels (petrol, diesel) these can contaminate the local land (and
therefore water courses). Where assessments for different hazards (i.e. fire and
environmental) indicate different standards are required then the most stringent control
measures should be applied.
Where multiple fuel types are installed on a site, it may be useful to consider the detailed
design of these areas separately, although the influence of each area on other aspects of
the filling station shall also be reviewed holistically within the risk assessment. This is
particularly important where there are a large number of variables and there are gaps or
inconsistencies in standards and guidance, as may be the case with these emerging
technologies. Risk assessments shall take into account the anticipated effects and
consequences, including those offsite, of potential fire and explosion hazards.
Recommended minimum separation distances to non-classified electrics on installations
are listed in Appendix 1 and Appendix 2.
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24 BCGA 41 – Revision 2
Fuel as
stored
Fuel
deliveries
Fuel as
dispensed
Compression Storage Pipework Dispenser
Hydrogen
(gaseous)
Cylinder /
tube trailer
/ on-site
generation Hydrogen
(gaseous) Optional Yes Yes Yes
Hydrogen
(liquid) Tanker
CNG Pipeline /
cylinders /
tube trailer
CNG Yes Yes Yes Yes
LNG Tanker LNG No Yes Yes Yes
Table 2: Typical components of a fuel filling installation
Where there is a desire to convert existing liquid-fuel dispense installations to gas fuel
dispensing (either as an exchange or both types together), the inherent hazards of the
various (and alternative) fuels with respect to buoyancy and ignition energy shall be
addressed through the DSEAR (14) risk assessment process.
NOTE: Such aspects will usually be significantly different to those encountered
when dealing with traditional liquid fuels alone. Consideration should be given to
unintentional releases, vents and leaks.
Forecourt design criteria for petrol filling stations can be obtained from the Petroleum
Enforcement Liaison Group (PELG), Petrol filling stations guidance on managing the
risks of fire and explosion (The Red Guide) (105) and the Blue Book (103 & 104).
Further information is available from the Energy Institute (EI) 15 (102), Model code of
safe practice Part 15: Area classification code for installations handling flammable
fluids.
NOTE: EI 15 (102) covers hydrogen installations in the context of refineries,
chemical plants, battery rooms and analyser houses.
Suitable access to all areas of the filling station for emergency personnel and equipment
shall be considered as part of the fire risk assessment. Refer to the Regulatory Reform
(Fire Safety) Order (15).
6.2 Location of storage installation
The location of storage vessels is often critical within a filling station layout. Storage
vessels are typically designed for external use; however, some components may require
weather protection. Wherever practicable, the storage installation should be located:
in an external area;
in an area that is secure;
where there is good natural ventilation;
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25 BCGA 41 – Revision 2
where there are no sources of ignition, or where any potential sources of ignition are managed, for example, in compliance with DSEAR (14).
Other locations are discouraged but may be considered after a suitable and sufficient
risk assessment has been completed.
Cryogenic storage vessels for flammable fluids shall be located in accordance with and
conform to BCGA CP 46 (95).
Where location of storage vessels underground is essential, recommendations for
underground natural gas storage installations can be found in IGEM/UP/20 (99), ISO
16923 (56), IGEM UP/21 (100) and ISO 16924 (57). Recommendations for
underground hydrogen storage installations can be found in ISO/TS 20100 (64) and
EIGA Document 171 (89), Storage of hydrogen in systems located underground.
Where there are enclosed or semi-enclosed storage areas (for example, to provide
protection from the weather), they shall be constructed in such a way as to provide no
opportunity for the build-up of flammable gases in enclosed or confined spaces.
Requirements for ventilation shall be determined according to BS EN 60079-10-1 (68),
Explosive atmospheres - Part 10-1 - Classification of areas - Explosive gas
atmospheres, or equivalent guidance as part of the DSEAR (14) risk assessment process
with hazardous areas defined as appropriate. Consideration should be given to any
potential hazards or risks relating to the location and operation of the installation.
Different layout requirements may be necessary for each fuel according to their
physical properties. CNG is typically stored at pressures of 200 bar to 300 bar.
Hydrogen may be stored at significantly higher pressures, up to 1000 bar. Separation
distances should take into consideration the gas pressures used. LNG and liquid
hydrogen are stored at lower pressures, typically less than 20 bar. However, they are
stored at low temperatures with LNG around -162 °C and liquid hydrogen around
-253 °C. Filling stations for cryogenic liquids require unique layout considerations to
allow for the management of released vapour. The layout and design should consider
the effects of a release of a cryogenic liquid, such that any release can rapidly evaporate
and will have only a minimum effect on the storage tank supporting structure, such that
the storage tank will remain adequately supported.
This requirement, location, efficiency and access to connecting pipework shall be
considered during the early stages of concept design, refer to Section 6.5.
Gaseous hydrogen bulk storage installations shall conform to BCGA CP 33 (92).
Further information on compressed hydrogen storage can be found in NFPA 2 (109)
and NFPA 55 (111), Compressed gases and cryogenic fluids code, also ISO/TS 20100
(64).
LNG bulk storage installations shall conform to BCGA 46 (95). Further guidance is
available in IGEM UP/21 (100) and ISO 16924 (57).
Further guidelines for general practice can be found in EIGA Document 114 (87),
Operation of static cryogenic vessels, and BS EN ISO 21009-2 (65), Cryogenic vessels.
Static vacuum insulated vessels. Operational requirements.
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26 BCGA 41 – Revision 2
Specific recommendations for liquid hydrogen storage can be found in EIGA
Document 6 (82). Further information for liquid hydrogen storage can be found in
NFPA 2 (109), NFPA 55 (111) and ISO/TS 20100 (64).
Specific recommendations for LNG storage installations can be found in BS EN 13645
(47). Further information for LNG storage installations can be found in IGEM/UP/21
(100), ISO 16924 (57), BCGA CP 46 (95) and NFPA 52 (110).
Physical separation of the storage installation from exposures or sources of hazard shall
be enforced to minimise the consequences of minor incidents. Consideration shall be
given to hazards arising from both flammable atmospheres and heat flux following
ignition. Consideration shall also be given to the method of delivery of fuel to the
storage installation. The DSEAR (14) risk assessment shall cover all hazards that may
arise during the delivery of fuel, and any additional control measures that may be
required during this period. Where necessary, guidance on vehicle impact protection is
included in Section 6.4. Consideration should also be given to impact avoidance for the
road tanker or mobile gaseous fuel trailer during offloading, and when the tanker or
trailer is parked (e.g. by using cones or possibly barriers). Vehicle refuelling whilst the
tanker or trailer is offloading should be justified by a suitable risk assessment. The
arrangements for delivery of fuels should be considered at an early stage, as this could
significantly increase the inventory at a site albeit it for a short period, and could
influence other aspects of the installation design (e.g. its floor -plan).
The separation distances in this document are intended as a guideline for both planning
authorities and system designers and installers. They are the minimum recommended
separation distances based upon generic considerations, which reflect both UK and
worldwide industry experience on design and installation of liquefied and compressed
flammable gas operations. It is the duty of the designer to ensure a comprehensive
viewpoint is given to separation distances at multi-fuel stations, including the differing
requirements for high-pressure ambient gaseous fuels and cryogenic liquid fuels.
Recommended minimum separation distances for hydrogen storage installations are
presented in Appendix 1. Where appropriate, these separation distances should be
applied both vertically and horizontally.
Recommended minimum separation distances for CNG and / or LNG storage
installations are presented in Appendix 2.
Based upon the details of a given installation it may be acceptable to reduce the
separation distances relative to those detailed in this document. Any reductions should
be justified based upon a site-specific risk assessment, or through the use of fire risk
modelling or standard mitigation factors (refer to the Blue Book (103 & 104) and
relevant industry documents).
The risk assessment shall specifically address the nature and use of adjacent property.
Recommended minimum separation distances may be extended where higher risks are
identified, for instance:
where the site is close to a heavily populated area;
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27 BCGA 41 – Revision 2
where the site is close to a vulnerable population: school, hospital etc.;
where the site is remote from external help (such as the fire authority);
where existing site conditions may foreseeably change on either a temporary or permanent basis, i.e. change of use, future planning considerations,
increased personnel or maintenance activities.
If a bespoke safety case is required, guidance on a number of different methodologies
that exist for the determination of recommended minimum separation distances can be
found in EIGA Document 75 (86), Determination of safety distances, NFPA 2 (109)
and ISO/TS 20100 (64). It should be noted however that these methodologies may give
distances that are not consistent with the minimum separation distances recommended
by the BCGA.
In the event of a spill of a liquefied fuel gas, the liquid will both rapidly evaporate and
travel until it settles at the lowest point (before full evaporation). It is important to
ensure containment of the spill above ground in an area remote from personnel, where
the liquid can evaporate safely without presenting a risk of asphyxiation, cold burns,
ignition, or thermal shock to mechanical components. Vapour clouds which fail to
quickly disperse may be blown by the wind and in some circumstances may have a
potential to blow far beyond the site with a potential risk of asphyxiation or ignition.
Where liquefied fuel gas leaks may have entered confined spaces, appropriate measures
should be taken before personnel entry in accordance with the Confined Space
Regulations (8). The actions to be taken in the event of a spill should be clearly
identified, trained for, and included in the emergency response procedure, refer to
Section 14.
Consideration should be given to the appropriate use of civil engineering features for
risk mitigation, for example diversion kerbs or grading, to ensure that liquid leakage
from any adjacent hazardous store is prevented from accumulating in undesirable
locations (e.g. within the fuel gas store). When liquefied fuel gas storage is present,
measures should be employed to prevent spilled liquid fuel gas from flowing onto the
forecourt, onto cold-sensitive components (e.g. non-cryogenic rated storage vessel
support legs or skirts), into public areas or in the vicinity of other features, for example
drains, manholes, culverts, etc. which might lead to the creation of a hazard elsewhere,
in certain circumstances. The design and construction of the station base should allow
for the safe dispersal (e.g. evaporation) of liquid leakage. Options such as boil-off
pads, sloped surfaces, pits, walls, bunds etc. may be considered in this respect, noting
that other hazards may thereby be introduced and so any such proposal should be
validated by risk assessment. Further guidance is contained in BCGA CP 46 (95).
Where appropriate, storage areas shall be designed to be readily accessible to mobile
supply equipment, refer to Section 3.3 and to mobile service and safety equipment.
The liquid storage installation shall meet the requirements of BCGA CP 46 (95).
Fencing, civil engineering and general provisions for non-liquid installations shall
follow the same principles (such as buffer stores, compressor houses, etc.).
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28 BCGA 41 – Revision 2
The minimum recommended separation distances of Appendix 1 and Appendix 2 shall
apply regardless of the position of the barrier or fence. If a fire resistant wall is used,
then by the methodology outlined in BCGA CP 4 (91), the safety distance may be
measured as the shortest distance around the ends of the wall to the storage installation.
An important principle in the hazardous area classification is the availability of
sufficient ventilation. The effect of firewalls can be to reduce ventilation, and this
should be considered in the site risk assessments. Firewalls shall provide a minimum of
30 minutes fire resistance in respect of integrity, insulation, and where applicable load
bearing capacity. Where the wall separates vulnerable populations from the dangerous
substance, the fire resistance provided shall be for a minimum of 60 minutes. Fire tests
are covered in BS 476 (37), Fire tests on building materials and structures.
If the storage area contains individual and / or bundles of cylinders, the layout shall be
designed to allow the use of suitable manual handling equipment and as appropriate,
forklift trucks.
Site areas where installations used for the production, storage and dispensing of
flammable liquids and gases and areas used for the delivery of fuels, shall not be
located beneath overhead electrical power lines. Installations shall be sited so that
damage to the installations or delivery vehicles by electric arcing from overhead or
other cables cannot occur.
6.3 Access and egress for fuel delivery vehicles
Access and egress may be required for delivery vehicles. For cryogenic flammable
fluids refer to BCGA CP 46 (95). Points for consideration include:
Protection of the tank(s) and pipes from vehicle impact, for example by barriers, bollards or kerbs. Guidance on vehicle impact protection is included in
Section 6.4;
Avoiding, wherever practical, the requirements for delivery vehicles to reverse;
Emergency arrangements for delivery vehicles and the delivery team; for example, requirements for the vehicle being able to drive away in a forward
direction without complex manoeuvring in the event of an emergency, subject to
the anti-drive-away provisions that should apply;
Hose lengths and hose handling arrangements; for example, parking post, storage space, purging, weather protection, capping, etc.;
Demarcation of the delivery vehicle parking location;
Signage, lighting and surface condition;
Drainage and spill arrangements from the delivery area;
The construction of the delivery pad surface, taking account of the actual delivery vehicle weight, size and layout;
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29 BCGA 41 – Revision 2
Space (including height clearance) for use of cranes, fork-lift trucks or other accessories when making deliveries; for example, bundles of cylinders;
Restriction of access to the tanker stand when deliveries are being made;
Restriction of access to the tanker stand when deliveries are not being made;
Line-of-sight maintenance from vehicle control position to tank gauges and indicators;
Line-of-sight maintenance from station control position to the tanker stand;
The position of any sensors, alarms, alarm repeaters, indicators etc. for the use of the delivery team including the on-site competent person;
Electrical earthing and equi-potential bonding facilities (and any necessary signage and instructions);
Supply of nitrogen or dry air for road tanker discharge operation. Where relevant refer to BCGA CP 44 (94);
Special site rules which may need to apply during (and immediately before and after) deliveries;
The impact on the site zoning under DSEAR (14);
Security (such as measures to prevent unauthorised removal of the road tanker or trailer from the stand, i.e. to prevent theft);
Anti-drive-away provisions, to prevent damage to the installation (including hoses) in the event of tanker drive-away.
For fuel delivery, the tanker stand should be designed and managed exclusively for that
purpose. If the delivery operation cannot be contained within a secured area, temporary
demarcation and/or other reasonable means (e.g. cones) should be considered to restrict
public access during the delivery process.
At stations where multiple fuels are stored or dispensed, simultaneous bulk deliveries of
differing fuels should be prevented unless a suitable risk assessment determines
otherwise. Further information on the delivery requirements of other fuels is detailed in
the Blue Book (103 & 104).
HSE L133 (78), Unloading petrol from tankers. DSEAR. Approved Code of Practice
and guidance, whilst prepared for the delivery of petroleum products to filling stations,
contains relevant transferable information on principles appropriate to the risk
assessment and safe delivery of fuels to filling stations.
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30 BCGA 41 – Revision 2
6.4 Location and installation of dispensing points
A specific area should be defined for vehicle fuelling. Wherever practicable,
dispensing equipment should be located outdoors in a freely ventilated area. Indoor
locations may only be considered after a suitable and sufficient risk assessment has
been completed. Further guidance for indoor hydrogen vehicle filling can be found in
NFPA 2 (109).
The location and proximity of dispensing equipment shall be established by risk
assessment. Based upon the details of a given installation it may be appropriate to
propose increased or reduced minimum separation distances relative to those detailed in
this document. Any reductions should be justified by, for example, the use of fire risk
and gas dispersion modelling or standard mitigation factors (refer to the Blue Book
(103 & 104) and other relevant industry documents). The minimum separation
distances within BCGA CP 4 (91) are recommended for the dispensing of gaseous
hydrogen. Once established, minimum separation distances and hazardous zone
requirements for additional dispensers and equipment shall be observed. For the
minimum recommended separation distances refer to Appendix 1 and Appendix 2.
Specialist storage and dispensing requirements for LNG shall be taken into
consideration when carrying out the risk assessment.
Where multiple dispensers are installed, e.g. for simultaneous refuelling, consideration
shall be given to the position of the dispensers and their proximity to planned or
existing dispensing equipment, storage and buildings, occupied and unoccupied.
When determining the location and positioning of dispensers consideration should be
given to traffic flow restrictions, traffic movements in the immediate vicinity of the
station, and the size and length of the vehicles to be refuelled. Measures to prevent
dangerous manoeuvres, for example, reversing into the path of traffic should be taken
when considering the design of the station and the location of dispensing points.
The vehicle fuelling area should be level, except for a minimal slope to aid surface
drainage.
Physical protection shall be provided to protect the dispenser from vehicular impact.
The characteristics of the specific vehicles to be fuelled at the installation should be
used to determine the civil engineering feature dimensions.
Height above the road
surface (mm)
Clearance between
dispenser and the edge of
the plinth (mm)
Stations serving light passenger
vehicles only 120 200
Stations serving heavy goods
and passenger-service vehicles 415 500
Table 3 – Typical dimensions for dispenser plinths
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31 BCGA 41 – Revision 2
Dispensers shall be mounted on a plinth (or ‘island’) unless alternative physical
protection is employed. Table 3 provides guidance on typical dimensions for dispenser
plinths. The dimensions in Table 3 take into consideration the large diameter wheels of
Heavy Goods Vehicles (HGV) or Public Service Vehicles and the typical vehicle
overhang. If a station is being designed with specific vehicle types in mind, it may be
possible to establish exact vehicle dimensions and hence design the station and plinth
for those vehicles. Alternatively, suitable protection shall be provided to prevent
mechanical damage to all parts of the installation and associated pipework, for example
by the use of crash barriers or bollards. The type of vehicle expected to use the filling
station should be considered when specifying physical protection measures. Physical
protection arrangements for commercial vehicle filling may need to be more robust,
larger and with greater clearances than for light passenger vehicles.
Plinths should typically be of reinforced concrete construction, with suitable kerbs.
Vehicle restraints are covered in BS 7669 (42), Part 3, Vehicle restraint systems. Guide
to the installation, inspection and repair of safety fences.
Dispensers and associated equipment may be housed in enclosures. Such enclosures
may change the extent of the DSEAR (14) hazardous area. This may assist in the siting
of electrical equipment, refer to Section 3. However, this advantage may be at the
expense of the potentially explosive area within the enclosure, hence classification
inside the enclosure or housing shall be carried out, and appropriate electrical devices
installed, refer to Section 7.1.
As with other areas of the filling station, where new or existing electrical equipment is
within the hazardous area surrounding dispensing equipment, this equipment shall be
rated for the appropriate gas group(s), for example, group IIC for hydrogen.
If a canopy is provided over the dispensing area, refer to Section 7.9.
All electrical devices or lighting mounted within hazardous areas around or above the
dispenser shall be appropriately classified. Where the accumulation of flammable gas
or vapour cannot be avoided, the inclusion of gas detection equipment should be
considered. The gas detection system should automatically stop filling operations and
render the installation safe, in the event of gas detection. Refer to Section 7.1.
Dispensers shall be secured against unauthorised use and access control measures
should be considered, for example, swipe card readers. The fuel gas supply to the
dispenser shall be capable of being isolated. To prevent unauthorised or inadvertent re-
activation of isolated services it is strongly recommended that the isolation point is in a
secure location. Where the isolation point is in an area accessible to the public or
unauthorised parties outside operating hours, it shall be fitted with appropriate security
devices.
6.5 Connecting pipework
Manifolds and fuel gas distribution pipework shall comply with the requirements of
BCGA CP 4 (91). CNG installation connections to gas supply network pipework and
manifolds shall conform to the requirements of IGEM UP/20 (99). Further guidance
for CNG storage as part of a vehicle filling station can be found in ISO 16923 (56) and
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32 BCGA 41 – Revision 2
NFPA 52 (110). The material of construction shall be compatible with the gas,
pressure and temperature.
Wherever practicable, the connecting pipework between production, storage and
dispensing equipment should be located in the open air. Where dispensers (especially
for cryogenic services) are located on remote dispenser islands pipework should be laid
in suitably constructed ducts.
All pipework shall be accessible to facilitate periodic inspection, examination and/or
testing.
Where there is a requirement to maintain the product as a cryogenic liquid then
pipework should be insulated, for example vacuum insulated, and kept as short and as
straight as is reasonably practical. This will assist in minimising boil-off.
Pipework should be marked with the pipe contents, and if possible the flow direction
and pressure and be colour coded. Where pipework is protected by insulation materials
then the identification markings are to be on the outside of the insulation.
6.6 On site fuel generation equipment and related process equipment
Fuel generation equipment shall be installed and operated according to the
manufacturer’s recommendations.
Where the equipment is fully enclosed, for example, for weather protection,
requirements for explosion relief shall be considered as part of the risk assessment.
Access is to be restricted to authorised personnel.
6.7 Vent systems
All gaseous fuels within the scope of this code are stored and used under pressure. As
such they are fitted with over pressure protection devices to release excess pressure
under normal operating conditions and in emergency situations such as fire. Manually
operated valves may also be fitted to release pressure, for example, for maintenance.
When these devices operate any product that is subsequently vented shall be dispersed
safely to reduce the risk of accumulation, ignition, or impingement on personnel,
equipment and buildings. This shall be achieved by the use of a vent system where the
product is released via a remote vent stack.
For information on the design, installation and marking of vent stacks installed for
cryogenic flammable fluids refer to BCGA CP 46 (95) and EIGA 211 (90), Hydrogen
vent systems for customer applications.
6.8 Vent recovery
Consideration shall be given to vent recovery and the prevention of boil-off gas
escaping from LNG vehicles and static equipment during the refuelling process, for
example, through the use of vapour recovery or vapour management equipment. Refer
to ISO 16924 (57).
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6.9 Other filling station activities
Consideration should be given to the layout of the filling station with relation to
vehicular and pedestrian movements arising from all other foreseeable filling station
activities, for example, petrol / diesel / LPG dispensing and deliveries, shop, tyre
inflation, car wash, customer parking etc. As far as is reasonably practicable, activities
unrelated to vehicle filling should be located outside of hazardous areas and vehicles
and pedestrians should not have to pass through hazardous areas to get to those
activities. The recommended minimum separation distances should be maintained.
Access requirements for personnel, plant and equipment shall be taken into
consideration for operational, maintenance, inspection, testing and decommissioning
activities.
Large vehicles should not have to perform complex manoeuvres and the site should be
designed and laid-out to facilitate this. An awareness should be maintained of
pedestrian movements around the installation, in order that hazards (for example, due to
driver’s blind-spots) may be minimised.
7. DESIGN OF FILLING STATION
7.1 General
The filling station shall be designed to minimise risk to users, operating personnel,
general public, nearby properties and the environment, as well as taking account of any
security requirements. This is referred to as safety by design; a concept which
incorporates fail-safe mechanisms, features and philosophy.
Commonly, potential methods of failure, the associated consequences and mitigating
safeguards are explored through a combination of risk identification and assessment
methodologies including DSEAR (14) risk assessments, Hazard and Operability
Studies (HazOpS or HAZOPS), Failure Mode and Effect Analysis (FMEA) and Layer
of Protection Analysis (LOPA). Where in-scope safety instrumented systems are
present, consideration shall be given to applying Safety Instrumented System (SIL)
techniques in accordance with BS EN 61511 (71), Functional safety. Safety
instrumented systems for the process industry sector. Specific and more detailed
information can be obtained from BS EN 61508 (70), Functional safety of electrical /
electronic programmable electronic safety related systems.
Designers engaged and involved in the outline definition, detailed design, specification,
installation and commissioning of installations in the scope of this document shall be
suitably competent and shall have experience in the relevant field(s). Table 4 provides
a guide to the competence requirements for Designers of specific types of installation.
The appropriate level of reliability of control and safety systems should be determined
through appropriate analysis and suitable risk assessment.
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Fuel
Storage
Competence and experience required in the fields of:
Compressed
gases Liquefied
cryogenic
gases
Flammables
including
ATEX/DSEAR
Pressure
systems
engineering
Fuel
dispense
equipment
Hydrogen
(gaseous) Y
N (unless liquid
is present) Y Y Y
Hydrogen
(liquefied) Y Y Y Y
Y (if in scope)
CNG Y N
(unless liquid
is present) Y Y Y
LNG Y Y Y Y Y
Table 4: Competence and experience guide
The installation shall have appropriate automated safety shutdown and isolation
capabilities and easily accessible manual emergency shutdown devices. For LNG
automated shutdown and isolation capabilities refer to ISO 16924 (57). Due regard
shall be given to the combination of shutdown and isolation functions for all other
hazardous products, systems and services on the filling station site, including
appropriately positioned emergency switching devices in accordance with the Blue
Book (103 & 104). Safety circuitry should be hard wired using suitable latching relays
or via a safety validated BS EN 61508 (70) compliant computer control system(s).
The design shall comply with DSEAR (14) (taking into account fuel buoyancy), the
PSSR (11) and, where appropriate, shall be CE marked to the relevant applicable
European Directives, such as:
The Pressure Equipment Directive, European Directive 2014/68/EU (PED) (34), implemented in the UK through the Pressure Equipment (Safety)
Regulations (21);
The Machinery Directive, European Directive 2006/42/EC (26);
The Low Voltage Directive, European Directive 2014/35/EU (33);
The Electromagnetic Compatibility Directive, European Directive 2014/30/EU (32);
DSEAR (14) / ATEX European Directive 99/92/EC (25);
European Directive 2009/104/EC (27) the Use of Work Equipment Directive for minimum health and safety requirements for the use of work
equipment by workers at work, implemented in the UK through PUWER (9).
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The design shall protect against hazards associated with loss of containment of fuel.
The designer should typically consider the following:
Minimising the number of potential release points and reducing the likelihood of release.
Ventilation to maximise dilution of leaked fuel, hence keeping any resulting mixtures below flammable limits and avoiding the build-up of potentially
explosive atmospheres or the risk of asphyxiation in confined spaces. Refer to
the Confined Spaces Regulations (8).
Fuel leak detection, refer to:
o BS EN 60079 (68) Part 29, 1 to 4, Explosive atmospheres. Gas detectors;
o Hydrogen sensing, BS ISO 26142 (67), Hydrogen detection apparatus. Stationary applications;
o Use of LNG low temperature sensors, ISO 16924 (57) to indicate product loss.
Emergency shutdown system(s), as appropriate.
Hazardous area classification including of potential leak points, vents (and any hazards arising from these vents) and drains.
Ignition protection, earthing and bonding to prevent static (and other) charge build-up.
Mitigation against the effects of ignition, for instance blast walls, explosion relief, fire protection, etc.
A major concern associated with the storage and dispensing of all vehicle fuels is the
risk of fire and explosion. Both electrical and mechanical equipment can be a source of
ignition.
The probability of a fire and explosion hazard is reduced by the provision of good
design and layout, as well as appropriate operating and maintenance procedures.
Generally there are two elements to fire risk assessment. The first is the special,
technical and organisational measures which, in respect of fuel stations, are essentially
the precautions required to prevent the outbreak and rapid spread of a fire or explosion
due to work activities concerning the receipt, storage and dispensing of vehicle fuels.
Secondly, appropriate measures need to be taken to address ‘everyday’ or general fire
risks. These include those measures necessary to prevent fire and restrict its spread and
those measures necessary in the event of outbreak of fire, to enable those present
(including the general public) to safely evacuate the premises.
These general fire precautions include the means for detecting fire and giving fire
warning, the means for fire-fighting, the means of escape, ensuring escape routes can
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be used safely and effectively by employees and members of the public visiting the site,
and the competence of employees in fire safety. The presence of a variety of different
fuel types, comprising a blend of flammable components with differing properties
including those soluble in water, may influence the form and consequences of any fire
and therefore the required range of the general fire precautions. It is of critical
importance that the presence of dangerous substances is taken into account in
determining the general fire precautions necessary. A fire risk assessment shall be
carried out in accordance with the Regulatory Reform (Fire Safety) Order (15). Fire
protection equipment shall be provided as required by the site fire risk assessment.
In hydrogen and high purity natural gas (LNG and CNG) installations consideration
should be given to the detection of a fire. When their flames burn they can be (in
daylight) difficult to detect by eye. The use of technologies, such as thermal imaging,
will be advantageous.
Other flammable substances and combustible materials shall not be stored or be
allowed to accumulate in the vicinity of the storage or dispensing areas.
Electrical installations shall as a minimum, conform to BS 7671 (43), Requirements for
electrical installations. IET wiring regulations.
All fixed electrical equipment located in hazardous zones shall have the appropriate
ATEX rating, refer to BS EN 60079 (68), Explosive atmospheres. Part 14, Electrical
installations design, selection and erection, taking into account the relevant gas group(s)
classification.
Where gaseous fuels and traditional fuels are dispensed at the same filling station,
mandatory requirements for electrical installations are detailed in the Blue Book (103 &
104).
Where applicable, electrical equipment which is necessary for the installation shall be to
BS EN 60529 (61), Specification for degrees of protection provided by enclosures,
protection class IP54 or better. For more severe environmental conditions protection class
IP55 (designed to protect against water jets) should be used.
Lightning protection may be necessary to comply with local conditions or site
regulations. Lightning protection should be considered and implemented as
appropriate, refer to BS EN 62305 (72), Protection against lightning.
Conductive parts (e.g. metal fitments) on the installation including fencing, gates,
tanks and all pipework, vent stacks and vent recovery hoses, shall be adequately equi-
potential (earth) bonded. Refer to BS 7430 (41), Code of practice for protective
earthing of electrical installations.
Where gas detection is identified as necessary within the risk assessment, a suitable gas
detection system is to be fitted. For information on gas detectors refer to BS EN 60079
(68), Explosive atmospheres – Part 29-2: Gas detectors – Selection, installation, use
and maintenance of detectors for flammable gases and oxygen.
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The locations for the gas detection equipment shall take into account the physical
properties of the respective gases, potential release points and areas where they may
accumulate.
Audio / visual alarms, along with appropriate warning notices, safety signs and
instructions, shall be positioned at strategic locations within the area and at control
centres, as determined by the risk assessment. Alarm levels are to be set to allow action
to be taken in the event of a release of product, providing an early warning system, but
not such that it creates false alarms; thus allowing time for personnel to evacuate the
area before hazardous conditions are reached i.e. flammability range and/or workplace
exposure limits are reached.
Detection equipment should be installed, maintained and tested in accordance with the
manufacturer’s recommendations. Alarms should be tested regularly.
All systems should be fail safe and programmable devices should have an appropriate
SIL (Safety Integrity Level) rating. The gas detection system and/or any process
control system, may interface with the emergency shut-down system.
Adequate lighting shall be provided to allow for the identification of the product(s)
(signage and labels), to allow normal operations, maintenance, manual handling
activities and deliveries to be undertaken safely, as well as to assist with security. The
light source used shall give suitable colour rendering to enable colour labelling to be
easily recognised by persons with normal colour vision. Lighting is required to be
appropriately located, lighting equipment and ancillaries shall be suitably rated for the
hazardous area (if any)