Functional Safety 2016

ABB Limited

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Tel: +44(0)1642 372000

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Registered Office:

Pavilion 9, Byland Way

3780764 England

Daresbury Park

Belasis Hall Business Park

Fax: +44(0)1642 372111

E-mail:

Daresbury, Warrington

Billingham TS23 4EB

VAT Reg No:

Cheshire WA4 4BT

United Kingdom

668 1364 13

United Kingdom

Analysis of PSM shortcomings from sample audits (*Research Metholology)

The research covered a broad range of PSM activites, however a large number identify specific

functional safety short comings, which can be directly related to at least one of the three questions:-

Not reviewing Process Hazard Analysis (PHA) assessments when designs are modified or new

ones introduced

Not updating Layer of Protection Analysis (LOPA) studies based on real reliability data

Not documenting PHAs well enough to pass on the nature of the hazardous event or the likely

consequences. This often means that the SIL determination stage has to ignore the poor PHA

output and start from scratch to identify hazardous events

Not identifying critical alarms based on the PHA

Not providing operators with information on how to respond to alarms

Not differentiating between safety critical and other systems. ABB found in certain cases that

the term ‘safety critical systems’ was not in place and therefore no differentiation in the

standard of testing for all systems

Not completing end to end proof tests of safety instrumented systems. ABB found that in

many cases the Electrical, Control and Instrumentation (EC&I) team specified the testing

requirements and end to end testing of ‘barriers’ was not in place and no reference to PHA

documentation was being made in determining testing requirements

Reduced maintenance on safety critical measurement devices leading to increased plant trips.

Frequent removal of some elements of trip systems during certain operation

No regular training in key hazards being given to operators. When conducting reviews ABB

often finds that operators are not aware of worst case credible events as a result of PHA

documentation not being shared and process safety training not being carried out effectively

Not investigating incidents adequately to identify potential new weaknesses