PSSR - compliant and competent

04 December 2023

THE PRESSURE Systems’ Safety Regulations 2000: S.I.128 (PSSR) provide a complete legal framework to control activities from design to installation, examination and keeping of records to name but a few. While some systems may be exempt from the PSSR regulations, all systems will be subject to at least the Health and Safety at Work Act 1974.

A Written Scheme of Examination is required for pressure systems 250 bar litres and above, which must be drawn up (and then certified as suitable) by a competent person. 

However, many compressed air system users / owners make changes to the system and neglect to update their scheme. Or they do not fully understand the roles and duties of a 'Competent Person' despite being responsible for the system and its operations. Reflecting this, it's worth taking a fresh look at the key components of a successful scheme.

PSSR - The basics  

According to the latest statistics from the Health and Safety Executive, there were 22 fatal injuries to workers in 2021/22, a slight increase on the previous reporting period and around 1.7 times the all industry rate. 

As a result, the HSE states that ‘everybody operating, installing, maintaining, repairing, inspecting and testing pressure equipment should have the necessary skills and knowledge to carry out their job safely.’

If pressure equipment fails during operation, it can cause serious injury or damage to property and it is therefore essential that users and owners of compressed air systems are fully abreast and remain compliant with all the requirements of the PSSR regulations, which are designed ultimately to keep installations, and personnel, safe.

Your obligations

When understanding the business’s obligations as a compressed air user, there is an important distinction to be made. The PSSR regulations identify two categories of personnel that are responsible for pressure equipment - 'the user' and 'the owner'.

The 'user' refers to the person or business who has control of the operation of the pressure system or such a vessel. Once a pressure system is installed, the primary duty for compliance rests with the ‘user.’

An 'owner' refers to the person who owns the pressure system or his/her agent and may not be responsible for using the system daily.

The regulations also place duties on designers, manufacturers or any person who supplies equipment intended to be part of a pressure system. This is to ensure that it is fit for purpose, to prevent danger. 

Whether the business or individual is deemed a user or owner under the terms of the PSSR regulations, these issues must be addressed upfront, and the system built to ensure full compliance.

This includes certain legal responsibilities and duties which must be considered. 

For example, before a system can be designed or installed it is the user or owner’s responsibility to ensure that the safe operating limits are specified (and that they are subsequently reviewed and kept up to date).  In addition, the user of an installed system and the owner of a mobile system must ensure that the system is kept properly maintained and in good repair, to prevent danger. 

Keeping the Written Scheme current

A key component of the PSSR regulations is that a Written Scheme of Examination (WSE) is required, as is a process for the periodic examination, reporting and record keeping of pressure systems.  And as previously mentioned, the responsibility for this WSE lies firmly with the business or individual deemed responsible for the system.

This is an important point to make, as BCAS members often comment that a user has made a change to the system but has not subsequently updated or altered the WSE to document this change - remembering that any amendments to the WSE must be signed off by a ‘Competent Person.’

As mentioned previously, the PSSR regulations are created primarily to ensure the safe operation of pressure systems.  Failing to update the WSE in line with any system changes can potentially expose operators to unsafe working practices, so it is vital to factor this important safety consideration into routine administration.

Competent persons 

The Approved Code of Practice (ACOP) Safety of Pressure systems (L122) also establishes the persons that are permitted to certify and carry out examinations under a WSE. In both instances, these are referred to as ‘Competent Persons.’

It is often the case that end-users are unsure who has signed off the scheme, or if the person is qualified to do so in law. In general terms, the role and responsibilities of the ‘Competent Person’ can be summarised as follows: 

  • carry out examinations in accordance with the WSE including:
  • review WSE and confirm it is suitable
  • produce a written report for each examination
  • notify user/owner of repairs required
  • identify action in case of imminent danger
  • agree postponements of examination, where appropriate
  • draw up or certify written schemes of examination

An important feature of the in-house competent person is that they should be independent from the operating functions of the organisation, and they must have sufficient authority to stop the use of the pressure equipment should the need arise.

There are three aspects to written schemes 

  1. The drawing up (Regulation 8)
  2. The certifying (Regulation 8)
  3. The examination (Regulation 9)

To be considered a ‘Competent Person’ for the purposes of carrying out the examination or certifying the Written Scheme of Examination, the engineer should have sufficient practical and theoretical knowledge and actual experience of the type of system under examination. This will then enable any defects or weaknesses to be identified and an assessment made of their significance in terms of the integrity and safety of the equipment. 

It is important to remember that where certification of a Written Scheme of Examination is required, the guidance clause 94 and clause 124 state that suitable 'Competent Persons' are qualified to incorporated or chartered engineer level. More information can be found in the BCAS Factsheet 315.

Bringing it all together

The PSSR can be misinterpreted as a complex regulation and therefore may be overlooked by businesses who do not have sufficient time or resource to navigate through the requirements. A few immediate points for you to action

  1. Do you have a WSE Written Scheme of examination?
  2. Do you and the relevant site team know where this scheme is kept? It should be a live and accessible document used to manage your pressure system safety.
  3. When was the last time you audited the scheme?  Is it a true representation of your pressure system and was it prepared after the year 2000 when the new regulation was published?
  4. Who has signed off your WSE? Are they qualified as a ‘Competent Person’ (the definition under the ACOP)

"Queries about the PSSR regulation and its ACOP feature as one of the most frequently asked questions on the BCAS technical helpline. After years as the technical officer for BCAS, I remain disappointed at people’s understanding of this regulation," Preece adds.

Almost daily we are approached by individuals who consider themselves a 'Competent Person' - but it is important that the definition of this term is understood in line with the regulation. 

BCAS and its members would like to see a licencing and regulation system so that a 'Competent Person' is registered along with his/her qualifications protecting system users from well-intentioned but poorly informed individuals. In addition, pressure systems should have their own UK wide database, just like the MOT system for cars, to ensure that amendments are filed, and examinations are undertaken on a timely basis.

BCAS offers a number of training courses, supported by specific factsheets to help guide users through the directive.

The Certificate in Understanding the Pressure Systems’ Safety Regulation training course is a blended learning workshop, which covers the written scheme of examination in relation to compressed air systems. It provides knowledge of the Pressure Systems' Safety Regulations (S.I 2000 No 128) and related standards and codes of practice and is designed to provide the understanding required as a user, manager, or provider of written schemes of examination. 

To find out more about the Certificate in Understanding the Pressure Systems’ Safety Regulation training course from BCAS and to book a place, please visit​

In addition, the Society has several factsheets available for free download from its website:

Fact Sheet 315 Competent person 

Fact Sheet 314-2 GB Pressure Systems Compliance & Written scheme  

Fact Sheet 306-2 PSSR Compliance & scope

For further information, contact your local BCAS member or email

Tel: 0207 935 2464