In this post, I’ll discuss two safety-related parameters: safe speed and safe standstill. Speed control is a very common machine function. Conveyors, mixers, pumps, and many other applications rely on variable-speed drives. Some speed parameters are also safety-related because variations in speed can increase the risk to workers. See this post for more information on…
Read MoreForce and injury — How hard is too hard? ISO/TR 21260 will help
Force represents the mechanical energy that causes injury to the human body. ISO/TC 199 has been working on answering that question since 2012.
Read MoreInstructions for Use – the New ISO 20607
Instructions are one of the basic items that users expect to get when they purchase a product, and yet these important documents are often poorly written, badly translated, and incomplete. Key product features are badly described, and information on features, settings and hazards may be absent. All of this despite the fact that the minimum…
Read MoreISO 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!
Read MoreISO 13849-1 Analysis — Part 5: Diagnostic Coverage (DC)
Post updated 2019-07-24. Ed. What is Diagnostic Coverage? Understanding Diagnostic Coverage (DC) as used in ISO 13849-1 [1] is critical to analyzing the design of any safety function assessed using this standard. If you missed a previous part of the series, read it here. In the last instalment of this series discussing MTTFD, I mentioned…
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