Health and and Safety Executive Management of installed safety instrumented systems (SIS) Sarabjit Purewal Principal Specialist Inspector BSc ACGI PGDip CEng MIET Humber Chemical Focus Group 21 July 2016 Crown June 2016
Agenda What is the issue Why guidance is needed What the guidance will cover How and when it will be applied
What is the issue IEC 61511 safety lifecycle covers concept to decommissioning stages. But management of installed systems is less well understood or applied. Little guidance on how to apply 61511 to installed systems. Majority of the SIS HSE comes across are installed SIS, many legacy predating IEC 61511.
What is the issue Duty holders not clear on what compliance looks like for legacy systems. HSE continues to find problems around management systems that had not been picked up by duty holders.
Do we require guidance Further guidance is not always the answer The issues were presented at InstM&C annual conference and debated at CDOIF (Chemical Downstream Oil Industry Forum) Also raised with some individual companies Consensus that guidance would be helpful
How is it being produced CDOIF task and finish WG set up to produce first draft by end of the year Review by stakeholders Q1 2017 Led by Peter Davidson (TSA chair, previously head of UKPIA) WG members include: EEMUA, HSE, TSA, EI, UKPIA, InstM&C.
What will the guide cover Provides a common framework. Short and concise document. Will have examples to illustrate what good looks like. It will be based on requirements of Ed 2 of 61511. Aimed at duty holders. It will be used by HSE. It will be useful to third parties. Focus on functional safety management. Ancedotal evidence suggests systematic failures are the main cause of incidents. Provides links to existing guidance where appropriate, e.g. CDOIF guidance on prior use, HSE guidance on proof testing etc. Not repeating guidance that is already out there.
What will the guide cover Covers key issues for installed SIS systems including legacy systems relating to: Functional safety planning Operation and maintenance Competency management system including third parties consultants and contractors
What will the guide cover Performance monitoring (incl: PSPI s). Is the SIS performing to the design basis and providing the required risk reduction Demand rate/deviation alarms Failure rate Proof testing deferrals Time for rectification of faults v. requirements
What will the guide cover Periodic review, FSA4 (when sufficient operating experience has been gained, or on an event. Demonstration of ALARP) Audits. What is the difference between FSA and audits. MoC. FSA 5 And their impact on adequacy of risk assessments, SRS, design, procedures and documentation
What will the guide cover- Application to legacy systems When FSA 4 is applied to legacy systems (i.e. any system installed prior to the current Ed of 61511) any improvements identified are subject to reasonable practicability test. Not generally the case that legacy systems will need to be replaced. Techniques and measures used for assessing systems are not new. The important point is that there is proper documented evidence and demonstration of ALARP. That evidence is unlikely to align exactly with IEC61511. Where there is little evidence available judgements need to be made about the SIS integrity but improvements to functional safety management systems should be reasonably practicable to make.
How the guide will be used Once published it will be available through HSE web site as CDOIF guidance for duty holders. It will be included in the HSE EC&I operational delivery guide. The requirement for managing installed SIS systems is already in the operational delivery guide. HSE already inspects on this topic. Link: http://www.hse.gov.uk/eci/index.htm The guide will provide a common framework.
Health and and Safety Executive Thank you - questions Crown June 2016