ERD Engineering Inspections Ltd carry out Written Schemes of Examination and inspection of Pressure Systems covered by the Pressure Systems Safety Regulations 2000 (PSSR).


The Pressure Systems Safety Regulations 2000 (PSSR) aim to prevent significant injury from the hazard of stored energy as a result of the failure of a pressure system or one of it's component parts.  PSSR requires pressure systems to be inspected in accordance with a Written Scheme of Examination (WSE) by a competent person who knows what they are doing.  It is important that the competent person is independent and impartial.

A Pressure system is any system made up of one or more rigid pressure vessels as well as associated pipework and any protective device.  Any equipment capable of operating at 250 bar litres or above, hot water boilers operating at more that 100'C or any vessel or pipework containing a relevant fluid at any pressure. These fluids include steam at any pressure, compressed or liquified gas (including air) at any pressure above 0.5 bar and any dissolved gas under pressure.

A whole host of equipment across all industries falls under PSSR. Examples of a pressure system are:-

  • Boilers and steam heating systems
  • Steam coffee machines
  • Compressed Air systems (fixed and portable)
  • Pressure cookers and autoclaves
  • Heat exchangers
  • Refrigeration plant
  • Valves, steam traps and filters
  • Pipework and hoses
  • Pressure Gauges

These are a few of the more common examples but many other things fall under the regulations too.  If you are unsure contact us for free advice.


The regulations require that any pressure equipment (new or otherwise) that falls into the PSSR requirements will need a Written Scheme of Examination and will be subject to regular inspection.  The type of inspection required will vary for different types of pressure system and will be covered in your WSE. For most pressure systems an in service and out of service inspection will be required, meaning they will be inspected whilst operating and whilst switched off.  These inspections must also be carried out by an independent and impartial competent person.

Our Engineer Surveyors are highly trained with years of experience of pressure systems and PSSR (2000).  We can offer a full end to end service for your pressure systems and as we are totally independent and impartial we do not profit from any recommendations, so we will always offer advice and guidance with the best interests and safety of your company in mind. 


A Written Scheme of Examination (WSE) is a legal document required on most pressure systems and must be written by an independent, competent person. your WSE will include:-

  • The type of inspections required
  • A description of all parts of the system to be inspected
  • The interval between inspections
  • Any identification numbers
  • An necessary criteria for inspection, such as isolation procedures, cooling down periods etc

A WSE is not a substitute for regular maintenance in line with manufacturers recommendations and regular inspections by a competent, independent Engineer Surveyor.


PSSR requires regular inspections of pressure systems. The competent person carrying out the Written Scheme of Examination will determine the frequency of the inspections, with the frequency varying from 12 months to several years, depending on the equipment, the operating conditions, its usage etc. The most common inspection frequency is 12 months.  The inspection frequency will be noted in your WSE and must be adhered to.

Speak to one of our experts for more information.