This is a question I have often been asked in the past. Most people I have spoken with don’t have a good appreciation of what this means and the purpose. From the IEC61511 perspective, designers of Safety Instrumented Systems (SIS) are required to justify the selection…
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Entries tagged with: IEC61511
- by Dr. Steve Gandy, CFSP
- Tuesday, April 08, 2025
- Functional Safety
What is Prior Use Justification & How To Achieve it?
- by Dr. Steve Gandy, CFSP
- Tuesday, June 16, 2020
- Functional Safety
What is Prior Use Justification?
When it comes to IEC61511 and the selection of equipment for use within Safety Instrumented Systems (SIS) and Safety Instrumented Functions (SIF), there are only two methods that can be used to justify selection: IEC61508 Certified devices for the required SIL or Prior Use Justification. Just…
- by Dr. Steve Gandy, CFSP
- Thursday, February 06, 2020
- Functional Safety
Why Bother With Systematic Issues?
You may be wondering why this question is being asked? Isn’t it obvious that systematic issues are important and need to be considered? It may be that some of you reading this blog may not even understand what is meant by systematic issues. In which case, it may surprise you to know…