Method Functional Safety

Operation and Maintenance (O&M)

For a SISSafety Instrumented System the “Operation and Maintenance” (O&M) phase is more than just operating and maintaining. The objective is to make sure that the SIS achieves it’s SILSafety Integrity Level level over the entire life of the plant and to ensure that the assumptions on which the SIL target were based are - and remain - true.

O&M activities are challenging at the best of times – but if the way these activities are to be carried out is not considered during earlier lifecycle stages (and at the SRS stage in particular), they may be made very difficult to implement.

O&M activities include:

  • Proof Testing – to ensure the SIS can operate as it should, by finding any dangerous undetected failures. (The “undetected” failures that proof testing is targetted to reveal are those that are “undetected” by internal diagnostic tests).
  • Management of Bypasses (if these have been allowed / specified by the SRSSafety Requirements Specification).
  • Initial and on-going training of Operators and Technicians.
  • Analysis of data (from proof test results, spurious trips, demands, bypass quantity and duration etc).
  • Routine inspection and maintenance activities.
  • Monitoring to ensure that the assumptions made during H&RAHazard and Risk Assessment are and remain true. Such as what is the actual BPCSBasic Process Control System failure rate? has the occupancy of a particular area changed? If any of these values vary from those assumed in the H&RA, the required risk reduction (and therefore the SIL) may change.

What =Method can do for you

  • =Method can deliver Functional Safety training for Operators and Technicians.
  • We can carry out or verify proof tests.
  • We can review or author O&M procedures and help set up appropriate KPI performance measures.
  • We can help develop suitable procedures.
  • We can carry out Stage 4 Functional Safety Assessments.
  • Our Cyber Security business unit can support implementation of appropriate Cyber Security Risk Management procedures and Risk Assessments. And we can train Operators and Technicians on the fundamentals of Cyber Security as it applies to them.

Most recent projects for Operation and Maintenance

Development of an Operations and Maintenance plan is to control the operation, testing, inspection and maintainenance of the SIS so that the required SIL and the designed functional safety are maintained according to the SRS.

Industry: FMCG
Topic: Operation and Maintenance

Drafting a Safety Plan to cover the Operations and Maintenance Phase of IEC 61511, covering typical activities such as calibration, replacement of parts, inspection, proof testing and making changes to operations and maintenance procedures. Also covers monitoring of relevant KPI’s and the responses required to faults and failures.

Industry: Chemical
Topic: Operation and Maintenance

Proof test of spray dryer SIF

Industry: Mining / Metal / Cement
Topic: Operation and Maintenance

Proof testing spray dryer SIFs

Industry: Mining / Metal / Cement
Topic: Operation and Maintenance

Proof test verification for drinks industry application

Industry: Brewing and Distilling
Topic: Operation and Maintenance

View all of our recent projects here

Functional Safety Consultancy

=Method's specialist, expert consultants support industries across the entire Functional Safety Lifecycle. If you need help please contact us.

Functional Safety Training

=Method delivers training in public venues, In-house and online. See more about how we deliver training here.

Functional Safety Lifecycle

Assessments at key Lifecycle Stages - Functional Safety Management

Planning throughout the Lifecycle - Functional Safety Management

Verification at every Lifecycle Stage - Functional Safety Management
Hazard & Risk Assessment Allocation of Safety Funct's to Protection Layers Safety Requirements Specification Design & Engineering Installation, Commissioning & Validation Operation & Maintenance Modification Decommission
Functional Safety Management
Functional Safety Audit
What is Functional Safety?What is functional safety?
I am new to this, how do i start?What is functional safety?

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