Pressure Systems Regulations

The Pressure Systems and Transportable Gas Containers Regulations 1989, SI 1989 No. 2169 have now been superseded by the Pressure Systems Safety Regulations 2000, SI 2000 No 128, which came into force on 21st February 2000.

Please note that:

• Cylinders, officially known as transportable pressure receptacles, are no longer included in the PSSR, but fall under the Carriage of Dangerous Goods Legislation.
• Calor is now unable to provide Written Scheme of Examination (WSE) for any its commercial customers. However, an example of how to prepare a WSE is explained here later.
• If you require further assistance, please either contact your Regional Office or the Calor Technical Helpdesk (01926 318497).

Introduction

The Pressure Systems and Transportable Gas Containers Regulations 1989, SI 1989 No. 2169, have come into force in stages since July 1990 with final full implementation on 1st July, 1994.

These regulations, hereafter referred to as the PSR, place statutory duties on people or companies who design, install, own and use certain types of pressurised equipment at places of work.

This information is intended to explain, in fairly simple terms, how the PSR affect you with regard to the Calor Gas liquefied petroleum gas (LPG) system installed at your premises.

The PSR are complex regulations, so this simple guidance cannot cover the requirements of the regulations in detail. The purpose is to alert you to the existence of the PSR and give basic guidance on them based on Calor Gas understanding of their application to LPG.

If you require more detailed understanding of the PSR you should obtain copies of the regulations, approved codes of practice or guidance prepared by the Health and Safety Executive and published by HMSO.

In any case, Calor Gas strongly recommends that you contact your insurance company to ensure that you comply with any specific requirements they may have.

NOTE: This information is concerned with Calor Gas LPG installations. However, it should be noted that the PSR also apply to compressed air, nitrogen and other gases over 0.5 bar gauge pressure, all steam systems and pressurised hot water if over 100°C.

A Calor Gas LPG installation is a "Pressure System" when it is:

• A bulk storage vessel (tank) and associated pipework.

• The pipework (and hoses) to which a cylinder (baffle) is connected. and the pressure is more than 0.5 bar gauge (about 7.5 PSI).

This occurs wherever the LPG is in liquid offtake or in vapour offtake installations generally up to the 2nd stage regulator, if fitted. These two types of installation, showing the extent of the "Pressure System", are shown in diagrammatic form in Figures 1 and 2 (below). These diagrams are not meant to represent the physical layout of the actual installation nor suggest that all the items shown are present or that other equipment is not present.

The PSR do not apply to the fuel systems of LPG propelled vehicles but do apply ro their refuelling stations.

Not every installation is the same and if you have any doubts please contact your Calor regional technical department for advice.

Who Owns What?

Because of the number of different types of installations it is not possible to give a definitive statement but the table below gives a typical breakdown of ownership. Again, in case of doubt contact your Calor regional technical department for advice.

Examples of Pressure System Boundary

The PSR place various duties on people and companies who:

• Design, construct, install and use pressure systems.
• Supply and fill gas cylinders.

For the cylinders which it supplies and fills and for those parts of bulk installations which it owns, Calor Gas will he carrying out all duties under the regulations, including those of the "user".

These duties include, but are not limited to, the design, installation, periodic examination, keeping of records, and maintenance of the system and the provision of operating and emergency instructions to you the "operator".

The terms "user" and "operator" have specific meanings within the PSR which are explained later.

Firstly, you should advise any visiting factory inspector who asks about your LPG installation that Calor Gas is the "user" of the parts which it owns and has taken on the "user's" duties. Any requests for technical information or copies of periodic examination reports must be directed to your Calor Gas regional technical department.

Secondly, you should have, and be familiar with, the operating and emergency instructions provided by Calor Gas and comply with them.

Finally, for those parts of the system which you own you must make arrangements to carry out the "user" duties. These can be briefly summarised as follows:

• Knowing the safe operating limits of the system: that is the pressure that each part of the system can safely withstand and the related temperatures. The limits for pipework systems normally installed for LPG are summarised in Appendix A. For other systems, the system designer or installer should provide this information.

• Ensuring the system is operated within the safe limits this may entail ensuring that regulators are correctly adjusted and in good condition, etc.

• Having a formal written scheme for the periodic examination of parts of the system. The scheme (known as the Written Scheme of Examination or WSE) must be written or endorsed by a competent person and has to cover :

  • Protective devices: that is hydrostatic relief valves, regulators having an outlet pressure over 0,5 bar gauge where the down-stream pipework cannot withstand the inlet side pressure, and pressure gauges.

  • Any pressure vessels including vaporisers.

  • Any parts of the pipework, including hoses, in which a release of stored pressure due to sudden mechanical failure would cause danger to a person

This last point is very important. The PSR are concerned purely with the potential dangers arising from the pressure energy stored in a system, not with the flammability of the product stored. Thus leaks of LPG which must be guarded against because of the risk of fire or explosion are not covered by the PSR. It is, however, essential that systems are maintained gas tight irrespective of the PSR.

• Ensuring that the parts of the system specified in the WSE are examined by a Competent Person at the prescribed intervals.

• Ensuring that the system is maintained in a safe condition.

• Keeping of copies of the examination reports and information about the safe operating limits, repairs and modifications, etc.

Where the LPG pipework is the only pressure system that you own and it consists of simple pipework, hoses, valves and hydrostatic relief valves, Calor Gas can provide a suitable WSE, an example of which is illustrated later. Your Calor Gas regional technical department can advise you of companies who can carry out an examination in accordance with this simple WSE.

Where your LPG system is more complex and includes vessels, vaporisers or aerosol filling equipment, etc. you will need to have a WSE produced specifically for your system. Established engineering inspection companies can provide this service as well as carrying out examinations in accordance with the WSE.

In no circumstances must any equipment owned by Calor Gas be included in your WSE.

The PSR use various terms and expressions with specific meanings, some of which have been used in this booklet.

The following definitions represent the Calor Gas interpretation of these terms as used in this booklet where they have not already been explained in the text:

"Competent Person" - a company, partnership or self-employed person who has sufficient training and experience to carry out the activity in hand.

In the case of producing or endorsing Written Schemes of Examination this will generally be an organisation which employs at least one chartered engineer with experience in the examination of pressure systems and knowledge relating to LPG.

Examinations under the WSE may be carried out by different, lesser qualified persons or organisations provided they have appropriate training and experience.

"Operator" - the company or person who operates a system owned by Calor Gas eg. a customer consuming gas from a vessel owned by Calor.

"Pipework" - the pipes, hoses, valves and any pumps, compressor, in-line filters, etc. connected to a bulk storage vessel or to which a gas cylinder is connected. It does not include pressure relief valves, hydrostatic relief valves or any regulators which are classed as protective devices.

"User" - the company which controls the operation of the system.

For parts of the system which it owns, Calor Gas is the user by virtue of its ownership, installation, filling with product, inspection and maintenance functions.

For parts of the system owned by you, you are the 'user".

"Written Scheme of Examination" is the formal written scheme for the periodic examination of the parts of the system which require it under the regulations referred to previously.

The following list gives some examples of further information which may help you understand and comply with the PSR.

Published and available from:

HMSO Publications Centre and HMSO book shops

• 1989: No. 2169. The Pressure Systems and Transportable Gas Container Regulations 1989. ISBN 0 11 098169 3.
• Safety of Pressure Systems Approved Code of Practice [COP 37] ISBN 011885514X.
• A Guide to the Pressure Systems and Transportable Gas Container Regulations 1989 - Guidance on Regulations [HS(R)30] ISBN 0 11 885516 6.

H&SE Books, P O Box 1999, Sudbury, Suffolk. CO10 6FS Tel. 01787 881165 and branches of Dillon book stores and Rymans.

• Pressure Systems and Transportable Gas Container Regulations 1989 - An Open Learning Course ISBN 0- 7176- 0687- 2.
• Written Schemes of Examination IND(G)178L C200.