Written Scheme Of Examination

Under the Pressure System Safety Regulations 2000 (PSSR) Statutory Instrument 128, users and owners of pressure systems are required to demonstrate that their ‘Pressure Systems’ are safe. Therefore, if any part of their system requires a Written Scheme of Examination (WSOE), they are required to get one of these put in place for their system before it is operated.

We commonly get asked if we can provide a WSOE for customers, PressBoost Ltd do not carry out WSOE’s, as per the HSE guidelines, these should be carried out by a competent person, i.e inspection bodies or consultant engineers of Chartered Engineer status. PressBoost Ltd are regularly required to assist with the internal examinations of pressure vessels during a WSOE. Therefore, should you or your WSOE provider require our assistance, do not hesitate to contact us.

When we carry out a statutory inspection and service of your pressure equipment, we will inform you of any and all vessels connected to your system and we will highlight those which require a WSOE. This is a simple calculation that we will carry out for you. The WSOE is a document that is relevant to pressure equipment that is operating under pressure and contains a relevant fluid. The relevant fluid in this instance is the gas in the vessel. This is the common misconception people make. They believe pressure vessels do not require a written scheme because water is not a relevant fluid under the WSOE. It is critical to remember that the relevant fluid is the gas, hence why some pressure vessels fall under WSOE.

The final thing to point out is why only some pressure vessels fall under WSOE. This is because to be classified as a pressure vessel which required a WSOE, it must exceed 250 Bar/Litres. This calculation is made by multiplying the volume of the vessel, by the pressure of the relevant fluid (i.e. the static gas charge).

N.B – A WSOE is a supplementary examination to be carried out as part of a maintenance regimen. All Pressure systems must be maintained under statutory requirements alongside a WSOE if required.

For more information on WSOE, please follow this link https://www.hse.gov.uk/pubns/indg178.pdf