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Random Versus Systematic Faults: What’s The Difference?
Oct 19, 2017[:en][vc_row][vc_column][vc_column_text]I saw and responded to a LinkedIn discussion on this very issue, where someone had asked “if I have a misaligned limit switch that fails dangerously, then is it random or systematic?”. This is an intriguing question because many view human error as being systematic and, whereas, this is sometimes true, it’s not always the […]
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Frequently asked questions about ANSI/CSA 22.2 No. 336 for Robotic Engineers
Jan 11, 2018[:en][vc_row][vc_column][vc_column_text]On January 5th CSA Group published the first edition of particular requirements for rechargeable battery-operated commercial robotic floor treatment machines with traction drives. CSA 22.2 – 336 is a National Standard of Canada. Why Should I Care? If you are a robotics engineer working for a company planning to sell floor treatment machines in North America […]
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Why is Safety Certification So Tough?
Jan 04, 2018[vc_row][vc_column][vc_column_text]Some organizations complain about the ‘high bar’ to comply with 61508. They complain that there is too much overhead in documentation and testing, and it all costs too much. Other organizations actually benefit from this ‘high bar’ as a barrier to entry for competitors. This is a differentiation factor for competitive advantage. So 61508 can […]
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[:en]The Undetected Detective – PVST[:zh]Why is Safety Certification So Tough?[:]
Nov 30, 2017[:en][vc_row][vc_column][vc_column_text]Have you ever wondered why some dangerous failures are classified as undetected and others are classified as detective? Aren’t dangerous failures all dangerous? Why do we classify them differently? Let’s say we have a plant that is running in normal operation mode and the system needs to trip. The safety function of this system is […]
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Human Factors in Alarm Management
Nov 02, 2017[:en][vc_row][vc_column][vc_column_text] Question: Which one of these layers of protection (operator response to alarm, relief valves, dikes and safety instrumented systems) is not like the other? Answer: Operator response to alarm (Operator Intervention) because of the “Human” factor. It is very difficult to calculate the probability of failure on demand (or the risk reduction factor) for […]
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What do you need to know about traceability for IEC 61508?
Oct 26, 2017[:en][vc_row][vc_column][vc_column_text]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. If you do it right, there […]