exida explains Blog

Entries tagged with: SIL Verification

Close Enough? Not so Much
  • by Denise Chastain Knight, P.E., CFSE, CCPSC
  • Wednesday, May 27, 2015
  • Functional Safety

Close Enough? Not so Much

Performing a SIL Verification calculation on preliminary design information can be a very useful tool to dial in the Safety Instrumented Function (SIF), Safety Requirements Specification (SRS) content , and define critical elements for the field component purchase specifications. Conceptual verification is typically performed quickly with general design information.…

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Getting Realistic Failure Rate Data - Part 5

Over the course of several blogs , I will talk about getting realistic failure rate data, where this failure data comes from, and how different methods of failure data analysis compare. I think if you understand this, you will begin to get a very good feel of what it…

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The Architectural Constraint Blind Side
  • by Denise Chastain Knight, P.E., CFSE, CCPSC
  • Thursday, August 27, 2015
  • Certification

The Architectural Constraint Blind Side

I did my homework, purchased certified devices, and specified physical redundancy. I expected an uneventful SIL Verification but the assessor is telling me that I have functions failing Architectural Constraints in the sensor and final element groups. How can that be? 

Low demand mode Safety Instrumented Function (SIF)…

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What do you need to know about traceability for IEC 61508?
  • by John Yozallinas, CFSE
  • Thursday, October 26, 2017

What do you need to know about traceability for IEC 61508?

Traceability is about connecting the dots to determine that the web of activities for a functional safety project have followed the proper paths.  Think of it like cheating at hide-n-seek; it provides a shortcut to find all those requirements and design parts that are hidden in your specification documents. …

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World Cup Fever & Failure Rates

World Cup Fever & Failure Rates

Do you have World Cup Fever? Well I do. Especially after the Netherlands (Holland) beat Spain 5-1 on Friday. I wished that was the score last time they played. So what does this have to do with failure rates? Sometimes my mind works in odd ways. While driving home…

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