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Safety and environmental standards for fuel storage sites
Final report
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Process safety performance indicators
276 HSE guidance
Developing process safety indicators: A step-by-step guide for chemical and
major hazard industries
HSG254 outlines six main stages needed to implement a process safety
management system. It provides a methodology for leading and lagging indicators to be set in a
structured way for each critical risk control system within the process safety management system.
277 OECD has also developed
Guidance on Safety Performance Indicators
116
to assess the
success of chemical safety activities.
278
Leading indicators
are a form of active monitoring focused on a few critical risk control
systems to ensure their continued effectiveness. They require a routine systematic check that key
actions or activities are undertaken as intended. They can be considered as measures of process
or inputs essential to deliver the desired safety outcome.
279
Lagging indicators
are a form of reactive monitoring requiring the reporting or investigation
of specific incidents and events to discover weaknesses in that system. These incidents represent
a failure of a significant control system that guards against or limits the consequences of a major
incident.
280
The six key stages
identified in the guidance are:
Stage 1 – Establish the organisational arrangements to implement the indicators
Stage 2 – Decide on the scope of the measurement system; consider what can go wrong and
where
Stage 3 – Identify the risk control systems in place to prevent major accidents. Decide on the
outcomes for each and set a lagging indicator
Stage 4 – Identify the critical elements of each risk control system (ie those actions or processes
that must function correctly to deliver the outcomes) and set leading indicators
Stage 5 – Establish the data collection and reporting system
Stage 6 – Review
Worked example
281 A worked example for developing process safety performance indicators, using HSG254
methodology, for a terminal fed by pipeline and by ship is included as Annex 1 of this appendix.
282 The example identifies potential leading and lagging indicators for challenges to integrity such as:
over-pressure of ship-to-shore pipework;
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accidental leakage from ship to water;
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bulk tank overfilling (ie above safe operating limits);
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accidental leakage during tanker loading;
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tank subsidence;
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leak from pumps;
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pump/motor overheating;
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corrosion of tanks;
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high pressure in terminal pipework during pipeline delivery;
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static discharge;
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physical damage.
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Summary
283 Dutyholders should ensure that a suitable active monitoring programme is in place for key
systems and procedures for the control of major accident hazards.
284 Dutyholders should develop an integrated set of leading and lagging performance indicators
for effective monitoring of process safety performance.