exida explains Blog

Entries tagged with: IEC 61511

WHY are Failures Occurring at a Different Rate from Our Other Site?
  • by Ted Stewart, CFSP, exidaCSP
  • Thursday, January 14, 2016
  • Certification

WHY are Failures Occurring at a Different Rate from Our Other Site?

Site audits have shown many differences in how things are done from site to site. This impacts many variables in a safety instrumented system!

A key metric for process industry designs is called average Probability of Failure on Demand (PFDavg).  After several studies of many field failure and proof…

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Why Is Functional Safety An Important Piece of Process Safety Management?

Why Is Functional Safety An Important Piece of Process Safety Management?

It’s interesting to note that with the release of the 2016 edition of IEC61511, there’s more emphasis being placed on the need for better functional safety management.  Having taught many courses on Functional Safety over the past few years, I find that most of the…

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Why Sharing Components Between SIS & BPCS Is Not A Good Idea

Why Sharing Components Between SIS & BPCS Is Not A Good Idea

This is a topic which comes up time and again, especially when reviewing legacy systems.  Although IEC61511 doesn’t preclude the use of shared devices, it does however provide guidance under Clause 11 of what the constraints are.  Even though the Safety Instrumented System (SIS) and Basic Process Control System (BPCS)…

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“Never tell me the odds”

“Never tell me the odds”

-Han Solo, Star Wars, Episode V: The Empire Strikes Back, 1980

I have enjoyed watching and reading about the actions of the fictional Star Wars character Han Solo over the years.  I recall hearing the above quotation more than once.  And as much as I enjoyed watching this character,…

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