exida explains Blog

exida just completed certification of a new sensor product that uses wireless communication to signal a safety logic solver of a potential problem.  Shortly after the certificate was posted, a challenge arose:  “How can wireless be used for safety?”  Well, it is different.  A designer must be fully…

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Functional Safety and Electromagnetic Interference (EMI) may not often be used in the same sentence. But EMI is just one of the environmental stresses that can stop a system from performing its safety function. It is important for a functional safety system to be immune from the EMI levels…

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Protection systems have been around for a long time, going back to having a canary in the mine, and throughout the Industrial Revolution; so they are not a new thing.  Various stakeholders were involved in business enterprises: owners, suppliers, consumers, community members, and workers. Usually the business owners held…

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IEC 61508 is considered a basic or “umbrella” standard for functional safety.  It is generic and sometimes even vague.  IEC 61508 was intended that various industry sectors provide their own specific standards and guidelines as needed.  Here we can see the relationship between 61508 and other standards, such as…

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I was reading an incident report on the Chemical Safety Board (CSB) website the other day, where it was the conclusion of the reviewing team that the incident (which sadly resulted in a loss of life) was the direct result of a poor safety culture across the…

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Formalize your process.

Companies often have a pretty good hardware development process in place, dealing with electrical and mechanical drawings, bills of material, and the factory floor interface.  Most of these processes are in place so the manufacturing department knows what to make and how to put it together. …

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Some of you reading this may not be aware or familiar with the terms “leading” and “lagging” indicators, when applied to Functional Safety.  The concept isn’t new but does provide significant benefit when applying this to Functional Safety because, if used correctly, these indicators can help significantly improve performance. …

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When I first heard this phrase, I was working in an R&D group developing electronic DCS.  My first interpretation was that until the Sales Department got an order for a new product, new ideas sort of sat on the shelf with low priority… meaning that people were probably working…

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An Interference-Free component, either as an interface or a defined functional area, is a system component that is neither safety critical (C3) nor safety relevant (C2), but interfaces with such subsystems. 

If a component has been shown to be interference free (C1), then it has been demonstrated that no…

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Part 1 of this blog entry discussed software modeling, modeling notation, and modeling tools. But, what does this have to do with Functional Safety?  The IEC 61508 standard has requirements, for certain SIL levels, regarding the use of:

• “Semi-formal methods”
• Computer-aided specification and design tools
• Design standards
• Performance modeling
…

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Have you even wondered, been involved, or WERE the little kid that didn’t listen to your parents, but always listened to a teacher?  This is called the “Third party effect.”  In business, it is well known that the power of persuasion can be the most effective by a third…

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Significant progress in process safety has been made by many companies and engineers around the globe. This progress is often overshadowed when a process safety accident hits the news.  In December of 2007, a runaway reaction led to an explosion at the T2 Laboratories in Jacksonville, FL.…

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I’ve been following some discussions from one of the online forums regarding competency and it’s clear from the correspondence that the issue of competency is still very subjective.  It made me think about “what is competency?” To me it’s a blend of knowledge and experience and just how well…

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The term SIL is rapidly spreading to Request for Proposals (RFP) and purchase requirements in many industries.  But in many of those industries, few have heard about SIL and fewer have a grasp of the fundamental concepts of SIL.  SIL is a term that means Safety Integrity Level. It is used…

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This is a question I often get asked when I’m teaching our FSE100 course on Functional Safety, when we discuss the purpose of Proof Testing and coverage.  It’s amazing how many end users assume perfect proof testing (i.e. 100% coverage), that is capable of finding, all the…

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