ISO 13849-1 Analysis — Part 8: Fault Exclusion

Post updated 2019-07-24. Ed. Fault Consideration & Fault Exclusion ISO 13849-1, Clause 7 [1, 7] discusses the need for fault consideration and fault exclusion. Fault consideration is examining the components and sub-systems used in the safety-related part of the control system (SRP/CS) and making a list of all possible faults. This is a non-trivial exercise!

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How Risk Assessment Fails — Again. This time at DuPont.

Casualty Evacuated by EMS

A recent report released by the US Chemical Safety Board (CSB) looks at a series of accidents that occurred over 33 hours on January 22 and 23, 2010, at the DuPont Corporation’s Belle, West Virginia, chemical manufacturing plant.

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The purpose of risk assessment

I’m often asked a simple question: “Why do we need to do a risk assessment?” There are a lot of good reasons to do risk assessments, but ultimately, the purpose of risk assessment is best summed up in this quotation: “Risk assessments, except in the simplest of circumstances, are not designed for making judgements, but…

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How Risk Assessment Fails – Fukushima Dai Ichi

Fukushima Dai Ichi Nuclear plant before the meltdown

The events unfolding at Japan’s Fukushima Dai Ichi Nuclear Power plant are a case study in ways that the risk assessment process can fail or be abused. In an article published on, Jason Clenfield itemizes decades of fraud and failures in engineering and administration that have led to the catastrophic failure of four of…

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CSA Z1002 Public Review – Only 15 days left!

Only 15 days remain to get your thoughts submitted on the draft of CSA Z1002. Do it now!

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