Written Scheme of Examination

A written scheme of examination is a document containing information about selected items of plant or equipment which form a pressure system, operate under pressure, and contain a ‘relevant fluid’.

 

Contents of WSE

Typical contents of a written scheme of examination include:

  • Identification of the items of plant or equipment within the system.
  • Those parts of the system which are to be examined.
  • The nature of the examination required, including the inspection, and testing to be carried out on any protective devices.
  • The preparatory work needed for the item to be examined safely.
  • Where appropriate, the nature of any examination needed before the system is first used.
  • The maximum interval between examinations.
  • The critical parts of the system which, if modified or repaired, should be examined by a competent person before the system is used again.
  • The name of the competent person certifying the written scheme of examination; and
  • The date of certification.

Drawing the WSE

  1. Identify which items of plant or equipment operate under pressure and form a pressure system.
  2. follow the steps described in the chart below
  3. check the exceptions to the Regulations, as you may find your pressure system does not require a written scheme of examination at all

Stems that Require a SWE

The following pressurised systems are likely to require a written scheme of examination:

  • Compressed air receiver and the associated pipework, where the product of the pressure in bars multiplied by the internal capacity in litres of the receiver is equal to or greater than 250 bar litres.
  • Steam sterilising autoclave and associated pipework and protective devices.
  • Steam boiler and associated pipework and protective devices.
  • Gas-loaded hydraulic accumulator.
  • The components of self-contained breathing apparatus sets (excluding the gas container).
  • Fixed liquefied petroleum gas (LPG) storage system, supplying fuel for heating in a workplace.