Best Practice for Risk Based Inspection

practice, as to the action taken to reduce the risk, may include the development of
sound operating and maintenance and inspection procedures.
The guidance also recognises that it is not always necessary to adopt the quantified
risk assessment approach but suggests that this method may be of help in setting
priorities when comparing risk values.
2.2. GUIDELINES ON PERIODICITY OF EXAMINATIONS
Guidelines have been published by various organisations giving advice on what
should be good practice when setting the intervals between statutory inspections of
pressure equipment. Three of these published guidelines are discussed below.
2.2.1. SAFed - Guidelines on Periodicity of Examinations
The Safety Assessment Federation (SAFed) is an organisation that represents the
interests of companies engaged in independent inspection and safety assessment of
engineering and manufacturing plant, systems and machinery.
Following the introduction of the PSTGCR in 1989 (2.8), SAFed considered that
there was a need for additional, practical guidance on the recommended intervals
between successive examinations of pressure systems. Guidance was also needed on
the areas to be investigated when considering an extension of existing intervals.
Consequently SAFed produced a set of guidelines on the periodicity of
examinations (2.9).
The Foreword of the guidelines states that they should only be adopted after proper
consideration has been given to the individual circumstances pertaining to each
pressure system. Guidance is given on the extending of intervals between
examinations including the factors and relevant information that should be
considered. Descriptions of the typical failure modes that can occur are provided.
The concept followed in these guidelines mirrors the basic qualitative approach to
risk assessment as detailed elsewhere in this document.
2.2.2. CEOC - Periodicity of Inspections of Boilers and Pressure Vessels
The European Confederation of Organisations for Testing, Inspecting, Certification
and Prevention (CEOC) represents the technical inspection organisations within the
European Union (EU). It was recognised that in the countries of the EU the interval
between the inspection of a given vessel can vary enormously without any apparent
technical justification. It was therefore decided to develop guidelines (2.10) to
advise the different bodies.
The first section reports a study that compares the current inspection intervals
throughout the member states. This study found that certain countries do not impose
any statutory duties on users of pressure systems to have plant examined whereas
other countries insist on the same type of plant to be examined every year. It is
evident from the examples used that the basis of examination requirements is not
one of risk.
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