Functional SafetyAsessments and Consultants

The standards are evolving to make it mandatory to carry out a Functional Safety Assessments at the end of a number of life cycle stages. The HSE will often specifically request that Functional Safety Assessments be carried out. The main point of the Functional Safety Assessment is to check that the work you did is appropriate for the SIL of the SIF.

Stage 1 Functional Safety Assessment

FSA 1 confirms that the work you did in Hazard and Risk Assessment and generating the Safety Requirement Specification has been done according to the standard - and by competent people. These tasks are fundamental to the safety of the final installation – having an independent expert confirm that all has been done correctly and that the required Safety Integrity Level has been achieved is a critical requirement of Functional Safety standards.

Stage 2 Functional Safety Assessment

FSA 2 confirms that the design is completed according to the rules of the standard. The design should already have been verified, but the FSA 2 looks in to the way in which the work has been done and confirms that people doing the work are competent. We also look at the devices chosen and confirm they are compliant with the target SIL, have the correct hardware fault tolerance and that the PFD calculations have been done correctly. If you have commissioned a 3rd party Systems Integrator to do this work for you, we can “police” the work they do on your behalf and ensure that what is delivered is compliant with the Functional Safety standards.

Stage 3 Functional Safety Assessment

FSA 3 confirms that the installation, commissioning and Site Acceptance Test (SAT) are completed according to the rules of the standard. We confirm that the process of introducing the SIF on to your plant and that the Validation (confirming that the installed system meets the needs identified in the Safety Requirement Specification) is done correctly at the Site Acceptance Test (SAT). We confirm that the installed system is compliant with the Functional Safety standards, prior to the introduction of any hazardous materials or processes.

Stage 4 Functional Safety Assessment

FSA 4 confirms that the ongoing operation, maintenance, testing, repair and record keeping are completed according to the rules of the standard. FSA 4 is a little different from FSA 1 to 3, in that is FSA 4 is repeated on a regular basis throughout the life of the plant. We recommend doing the first FSA 4 a year after the installation of a new SIS, then repeating it immediately prior to the re-HAZOP (perhaps every 5 years). The objective is to confirm that you are maintaining the SIL of the SIF over its lifetime – and that your record keeping is done so that you can confirm that the assumptions, on which the SIF design was based, are still true.

Stage 5 Functional Safety Assessment

FSA 5 confirms that modifications are completed according to the rules of the standard. An FSA 5 varies as much as modifications vary - it is inevitably a “customised” approach, given that no two modifications are the same. The FSA 5 is done it two parts – the first after the impact analysis is produced, to confirm that the planning for the modification is done well and the second after the modification is installed. The objective is to confirm that the modification does not have unintended (unsafe) consequences, that safety is maintained during the modification and that the new installation meets the required SIL.