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Pressure Systems Safety Regulations 2000



The Pressure Systems Safety Regulations 2000 (PSSR) came into force on 21st February 2000.

In order to accommodate the implementation of the Pressure Equipment Directive (PED), adopted in May 1997, the Pressure Systems and Transportable Gas Containers Regulations (PSTGCR) (SI 1989 No 2169) have been revoked and replaced with new consolidated regulations, the Pressure Systems Safety Regulations 2000. Transportable gas containers were removed from the scope of PSTGCR by the Carriage of Dangerous Goods (Classification, Packaging and Labelling) and Use of Transportable Pressure Receptacles Regulations 1996 (CDGCPL2) (SI 1996 No 2092). Transportable gas containers are covered by CDGCPL2 as transportable pressure receptacles.

A full copy of the Regulations can be printed and/or downloaded from:

The regulations contain requirements for the design, installation, commissioning, use, testing and inspection of pressure systems.

A pressure system is defined as:-

  • a system comprising of one or more pressure vessels of rigid construction, any associated pipework and protective devices;
  • the pipework and its protective devices to which a transportable pressure receptacle is, or is intended to be, connected; or
  • a pipeline and its protective devices;

which contain or is liable to contain a relevant fluid, but does not include a transportable pressure receptacle.

'Relevant fluid' means:-

  • steam;
  • any fluid or mixture of fluids which is at present greater than 0.5 bar above atmospheric pressure, and which fluid or mixture of fluids is:-
    • a gas, or
    • a liquid which would have a vapour pressure greater than 0.5 bar above atmospheric pressure when in equilibrium with its vapour at either the actual temperature of the liquid or 17.5 degrees Celsius; or
    • a gas dissolved under pressure in a solvent contained in a porous substance at ambient temperature which could be released from the solvent without the application of heat.

Construction Industry

In terms of the construction industry this will relate to the commissioning of pipelines normally used to convey fuels and other volatile fluids or gasses (relevant fluids).

Some air conditioning systems operate at pressures sufficient to attract the regulations as will associated air conditioning units or refrigeration systems with 25kw compressors or larger.

Mobile air compressor units would also fall under these regulations.

Amongst the systems excluded from the requirements of the regulations are:

  • Tyres
  • Portable fire extinguishers (below 25 bar @ 60°C and less than 23kg)
  • Hydraulic braking, steering, suspension systems etc. on vehicles
  • Diving compressors
  • Compressed air manlocks, airlocks or chambers.

Duties are placed on the 'users' of fixed installations and the 'owners' of mobile systems.


The regulations place a duty on designers of pressure systems to properly design the systems to that, when properly constructed from suitable materials, they do not present danger. The designers should also make sure in their designs that any necessary testing and examination may be performed without risk to health and safety. This would include provision for safe access into vessels, if required, and the provision of any necessary protective devices to prevent danger, so far as is reasonably practicable.

Designers of pressure equipment and assemblies also have to comply with the requirements of the Pressure Equipment Regulations 1999 [SI 1999 No. 2001] which requires certain design parameters to be maintained, conformity assessments and testing, and the provision of an identifying CE mark.


The information shown below must be specified for, applied to and maintained on pressure vessels by, as appropriate, the designers, manufacturers and operators.

  • The manufacturer's name.
  • A serial number to identify the vessel.
  • The date of manufacture of the vessel.
  • The standard to which the vessel was built.
  • The maximum allowable pressure of the vessel.
  • The minimum allowable pressure of the vessel, where this is other than atmospheric pressure.
  • The design temperature.

The marking should provide immediate maximum/minimal pressure information to operators and particular identification for examination and testing purposes and records.

No mark or plate must be removed from a pressure vessel.


Sufficient written information should be provided to ensure compliance with the regulations and to prevent danger. This information would include the design, construction, examination, operation and maintenance parameters and requirements as could reasonably be foreseen as being required. The information supplied must be amended to reflect the current condition if the pressure system is modified or repaired.


The contractor responsible for the installation of a pressure system has a statutory duty to perform the installation so that nothing about the way in which it is installed would give rise to danger, adversely affect the operation of the protective devices or inhibit the ability to perform future inspection work. Duties extend to ensuring that any maintenance activities can be performed safely (e.g. the installation should provide for maintenance and examination access).

Safe Operating Limits and Operation

No person may operate a pressure system unless the safe operating limits have been established and a written procedure provided to ensure the safe operation of the system, including any specific precautions and emergency arrangements. No person should operate a pressure system unless he has been provided with this written procedure.

Mobile systems must also be legibly marked with the operating limits.


No pressure system may be operated unless a written scheme for the periodic examination, by a competent person of specific parts of the system has been provided. This examination would include pressure vessels, pipework, pipelines, valves, compressors, pumps, hoses, protective devices, etc. The competent person would be deemed to be competent due to his/her knowledge, experience and training, and would normally be an engineering insurance company employee, although it may be the user or owner.

The competent person must ensure that the written scheme is suitable and that it includes the following:

  • Details of the nature and frequency of examination.
  • The measures necessary to prepare the pressure system for examination without risk to the examiner or others.
  • Requirements for examination prior to first use of the pressure system and/or subsequent to modification and/or repair.

An examination report should be prepared by the competent person and sent to the operator of the pressure system (and the owner if the operator is not the owner) within 28 days of the examination completion.

This report should include the following:

  • A listing of the pressure system components examined, the condition of those components and the results of the examination.
  • The competent person's opinion as to the need for repairs, modifications or changes to the safe operating limits of the pressure system which are needed for the continued effectiveness of protective devices and to prevent danger. The competent person must specify the date by which the repairs, modifications or changes to the operating limits must be completed.
  • The date for the next examination, as specified by the scheme of examination, after which the pressure system should not be operated, unless this examination has been undertaken.
  • A statement by the competent person on the continuing suitability of the scheme of examination to prevent danger, or modification required together with the reasons for such modification.
  • The name and signature of the competent person making the report, together with the date of signing.

The date for the next examination may be postponed by agreement, in writing, with the competent person, providing this postponement will not endanger people. Only one postponement is allowed and the user or owner of the pressure system must notify the enforcing authority of the postponement. If the competent person performing the examination has the opinion that the pressure system and/or certain components of the system present imminent danger he/she should immediately report this in writing to the owner/user of the system and follow this with a written report to the enforcing authority within 14 days. If this should occur, the pressure system should not be operated until any remedial action has been successfully completed, together with any further testing and/or examination necessary.


The user or owner of a pressure system must ensure that arrangements are in place for the maintenance of the system so that danger is prevented.


The user or the owner of a pressure system are required to keep the last examination report and any other report that could assist in assessing the safety of the system, particularly in relation to repairs and modifications. Any notification of imminent danger or postponement of examinations should also be retained until the necessary actions have been carried out. These records should be kept at the premises in which the pressure system is located or, for mobile systems, at the premises from which the mobile system is controlled.

If a pressure system is sold to another party, these records must be passed to the new owner as soon as possible. In addition, any design details and the schedule of examinations should also be passed to the new owner.

Content of the Regulations

Part 1 - Introduction

  1. Citation and commencement
  2. Interpretation
  3. Application and duties

Part 2 - General

  1. Design and construction
  2. Provision of information and marking
  3. Installation
  4. Safe operating limits
  5. Written scheme of examination
  6. Examination in accordance with the written scheme
  7. Action in case of imminent danger
  8. Operation
  9. Maintenance
  10. Modification and repair
  11. Keeping of records, etc
  12. Precautions to prevent pressurisation of certain vessels

Part 3 - Miscellaneous

  1. Defence
  2. Power to grant exemptions
  3. Repeals and revocations
  4. Transitional provision
    • Schedule 1: Expectations to the regulations
    • Schedule 2: Modification of duties in cases where pressure systems are supplied by way of lease, hire or other arrangements
    • Schedule 3: Marking of pressure vessels

HSE ACoPs and Guidance

All HSE documents are available to purchase or to freely download from the links below.