Machinery Safety 101

ISO 13849-1 Analysis — Part 6: CCF — Common Cause Failures

Post updated 2019-07-24. Ed. What is a “Common Cause Failure”? There are two similar-sounding terms that people often get confused: Common Cause Failure (CCF) and Common Mode Failure. While these two types of failures sound similar, they are different. A Common Cause Failure is a failure in a system where two or more portions of the…

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ISO 13849-1 Analysis — Part 5: Diagnostic Coverage (DC)

A graph showing the theoretical "bathtub curve" for product failure rate over the lifetime of the product.

Post updated 2019-07-24. Ed. What is Diagnostic Coverage? Understanding Diagnostic Coverage (DC) as it is used in ISO 13849-1 [1] is critical to analysing the design of any safety function assessed using this standard. In case you missed a previous part of the series, you can read it here. In the last instalment of this…

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