Importance Of Pressure Systems Safety Regulations

The loss of life, property damage and disruption caused by even a small leak in pressure equipment can be devastating. This is why maintaining compliance with PSSR is vital to businesses.

PSSR applies to any qualifying pressure system holding liquids, gases and vapours which exert a pressure. This TAG offers supplementary guidance to support the PSSR Approved Code of Practice (ACOP) and supporting guidance.

Risk Assessment

A well-considered risk assessment should be the foundation for all of your work with pressure systems. It should cover all aspects of your operation, including the skills, knowledge and experience of those operating the equipment and ensuring that they know what to do if something goes wrong.

This assessment should also determine what sort of pressure systems you have and what the risks of those pressure systems are. Any system that contains a “relevant fluid” – which includes steam at any pressure, fluids at more than 0.5 bar above atmospheric and gases dissolved in solvents – must be subject to regular formal examinations by a competent person.

Safe Operating Limits

When it comes to pressure systems safety regulations, Safe Operating Limits (SOL) are a key element. At prescribed intervals companies should review the SOL of equipment they are using to ensure it is within its designed limits. This involves a detailed review of the equipment in service, its design parameters and current protection systems and alarm functions.

SOL definition may also occur during the initial design of a piece of equipment. In these cases, a ‘margin’ is used to define upper and lower limits around a target operating value. This enables equipment to be designed with mechanical integrity in mind and can help to reduce maintenance costs through a reduction in the number of retests required.


Whether it is an industrial steam boiler or a gas cylinder, if a pressure vessel fails it could cause serious injury and damage. Therefore, it is important to inspect them as required by PSSR.

A WSE (written scheme of examination) is a legal document that must be prepared, reviewed and updated by a competent person to specify which items of plant and equipment form the Pressure System and which are to be examined. It should also specify the frequency of the examinations.

A good way to assess a pressure vessel’s condition is by using radiography. This is where a trained technician uses gamma or X-rays to produce an image of the pressure system. This shows any holes, discontinuities or other defects that would expose people to danger.


The duty holder has the responsibility to make sure that regular inspections are taking place and that pressure equipment is compliant. This is achieved through a Written Scheme of Examination which specifies the equipment to be examined and the frequency of the examinations. It is also the responsibility of the duty holder to ensure that the ‘competent person’ carrying out the examinations has the necessary breadth and depth of knowledge and experience.

Pressure systems include any’system’ made up of one or more rigid pressure vessels with their associated protective devices and pipework or pipelines that contain or are liable to contain a’relevant fluid’. This includes steam, gases under pressure, and fluids artificially kept under pressure that become gas when they are released.