exida explains Blog

Though this is largely true, I want to discourage people from completely ignoring the good things that IEC 61508 does for the end user.

IEC 61511 is the process industry functional safety standard derived from IEC 61508. In the very first section of IEC 61511 (“Scope”), the standard describes…

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Splint is offering to present a “special reward” to the “first person to produce a real program that produces no errors with strict checking.” Here’s a summary of a recent real-world automotive project attempting this.  

TL;DR: We were not successful, but we learned a few things about MISRA compliance. Feel free to skip to the Observations section to learn more. 

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The new release of IEC61511:2016 has caused some confusion when it comes to the Functional Safety Assessments (FSAs). Which ones are mandatory?

The confusion comes from the wording in the standard and the clarifications in the notes. The relevant clause in the standard 5.2.6.1.4 states:

A FSA team…

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When I was a kid, I liked watching the Jetsons.  I felt certain that by the year 2000 we’d all be enjoying those flying saucers and futuristic homes.  Imagine my disappointment that in 2018 we still drive on 4 wheels… and my home cannot elevate itself above bad weather……

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In this blog series, I will cover the emerging trends in the valve assembly market, how these trends relate to the IEC 61511 requirements, and what's in a final element. When you look at the different devices that go into some of these safety systems, the final element becomes…

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Ehh… If your safety action is stopping flow/closing a valve, how are you going to accomplish this if you consider that the remote actuated valve is not part of your SIF ?

So, what is this myth based on? The title of IEC 61508 reads “Functional safety of electrical/electronic/programmable…

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Estimating time and cost for a project, or even part of a project, can be tricky.  Breaking down the tasks into subparts must be done or you don’t stand a chance.  Given enough time, you can develop an accurate estimate and put a good plan in place.  But sometimes…

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Both IEC 61508 and ISO 26262 highly recommend a modular approach to software development. One question that comes up regularly asks if there are quantitative targets for determining whether sufficient progress has been achieved by software engineers.

IEC 61508-3 Table B.9 Modular approach

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• by Steve Gandy, CFSP
• Thursday, February 22, 2018
• Functional Safety

What Managers Need To Know About Functional Safety

If you’re a manager in the process industries then you should be familiar with the concept of Functional Safety and the need to have well defined processes and procedures in place.  If not, then how else will you be able to ensure that your Safety Instrumented System and plant…

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• by Jonathan Moore
• Thursday, January 11, 2018
• Functional Safety

Frequently asked questions about ANSI/CSA 22.2 No. 336 for Robotic Engineers

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…

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• by John Yozallinas, CFSE
• Thursday, January 04, 2018
• Certification

Why is Safety Certification So Tough?

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…

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• by Loren Stewart, CFSE
• Thursday, November 30, 2017
• Functional Safety

The Undetected Detective; PVST

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…

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• by Todd Stauffer
• Thursday, November 02, 2017
• Alarm Management

Human Factors in Alarm Management

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…

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• by John Yozallinas, CFSE
• Thursday, October 26, 2017

What do you need to know about traceability for IEC 61508?

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. …

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• by Steve Gandy, CFSP
• Thursday, October 19, 2017
• Functional Safety

Random versus Systematic Faults: What’s the difference?

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…

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