Functional SafetyAsessments and Consultants

Specialist Functional Safety Consultants across all phases of the lifecycle

=Method offers Functional Safety Assessments and Consultancy across all the phases of the Functional Safety Lifecycle. We have a broad range of experience with different members of the team specialising in different phases of the Functional Safety Lifecycle.

Discuss your Assessment or Consultancy needs

Functional Safety Asessments and Consultants

Functional Safety Assessments

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.

Functional Safety Audit

The main purpose of an FS Audit is to confirm that your procedures, if you were to follow them, would deliver compliant Safety Instrumented Functions. Combined with an effective Functional Safety Assessment programme, this ensures that the procedures are compliant and that projects follow the procedures. An FS Audit should be repeated on a regular cycle to ensure the procedures are up to date and being followed – if required, the FS Audit can be used as the basis of certification of your Functional Safety Management approach.

Competency Assessment and Management

Management and assessment of competency is a key requirement of the Functional Safety Standards. If required, we can perform Competency Assessment on your staff, so that you can be sure they have met the required levels of competency. If you require a Competency Management tool please see the Method Competency Management tool.

Fine Tuning Procedures

The work you do is guided and controlled by procedures – but tuning these procedures so that you achieve compliance without an unreasonable drain on resources, is a difficult balancing act. And the best procedures can ensure projects are delivered right-first-time, minimising costly re-work. The work we do to help you improve is normally captured in changes to your procedures, so the benefits we deliver continue in to the future.

Any Lifecycle Phase

We have a broad range of experience in Functional Safety, with different members of the team specialising in different phases of the Functional Safety Lifecycle. We can do this work, but we prefer to support you to do the basics yourself.


As you develop your Functional Safety capability and confidence, you may want a real expert to check your work. We can do this for any life-cycle phase.

Consultancy Enquiries

If you have any questions, please contact us on or +44 (0)1462 713313

Our approach is to develop your knowledge and competency so that you can continue working once our work is done.

Recent =Method Projects

Stage 2 & Stage 3 Functional Safety Assessment
A Stage 2 and Stage 3 Functional Safety Assessment of a Spray Dryer installation at a precious metals recovery site. A small but challenging project with some challenges in relation to the compliance justification for the contactor final element
Risk Assessment of a high voltage test machine
A risk assessment of a high voltage test machine to determine compliance with IEC 61508 after having been designed to meet IEC 62061 and ISO 13849.
PUWER Assessment
A PUWER assessment of a depositor machine.
Expert Witness
Acting as an expert witness in court case relating to a problematic functional safety project.
First functional safety project
Providing consultancy to a systems integrator embarking on their first functional safety project.
Updating the Layer of Protection Analysis (LOPA)
Reviewing and updating the Layer of Protection Analysis (LOPA) for a fuel storage application. Assisting the client to respond to very detailed analysis from the HSE – and identifying a future approach to hazard and risk assessments.
Proven in Use assessment of a valve
Carrying out a Proven in Use assessment of a valve. Also included a Prior Use assessment on the client site, an FMEA of the device and a manufacturing assessment - with a number of =Method specialists involved in the different aspects of the project.

E: T: 44 (0)1462 713313. W: