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Cyber Security, Beyond the Internet: An Automation Engineer’s View

The world of automation has changed significantly over the past 30 years.  I have fond memories of starting my career by calibrating, adjusting, and tuning pneumatic control loops while working my way through the electronic age right up to the present digital and cyber generation of automation.  If you…

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  • by Dave Butler, CFSE
  • Wednesday, July 10, 2013
  • Software

Tracing and Validation Test Planning

Please see the first entry of the Requirements Management blog series here

Please see the second entry of the Requirements Management blog series here

So, you have a set of detailed safety requirements.  You have derived them down to a level of detail you feel spells out…

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  • by Dave Butler, CFSE
  • Tuesday, June 25, 2013
  • Software

Allocation vs. Derivation

Please see the first entry of the Requirements Management blog series here.

The concepts of allocation and derivation are sometimes misunderstood when it comes to requirements management.  This can lead to confusion and even to safety problems.  The process of derivation involves the writing of a new requirement, …

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I have just one more, small change…

How many development teams have heard those few, innocent words uttered from Marketing/Management toward the end of the development phase of a project, only to have their schedule blown out of the water?  The phase of development into which the change is introduced determines the size of the concentric…

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Fire, Aim, Ready!

There is usually a natural order to things. But there are times when the natural order gets disrupted, and this could be for any number of reasons:  we get busy, overloaded with tasks or information, tired, complacent, etc.  But when you think about it, most of the excuses we…

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Safety Training Benefits Safety Culture

While attending the Offshore Technology Conference, I heard a speaker make the point that studies substantiate that employees who are trained in safety are involved in fewer accidents.  Those of us who promote and provide training in safety, this comes as no surprise.  But it was his next…

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If There Was ONE THING to Know About Functional Safety

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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Why Do We Need You?

This was a question posed to me by an engineering contractor the other day.  Although I found the question quite strange, it made me think “okay, why do they need us?”  I suppose there are a few answers:

  1. Regarding the end user perspective, we exist to provide an independent third-party…

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Make IEC 61511 into a Cookbook?

IEC 61508 and IEC 61511 are known as “performance” based standards.  Specific design rules, as found in “prescriptive” standards, are not included, allowing for innovation and new technology, as well as creativity and advancement.  However, it does imply that a certain level of competency is required.

Others would strongly…

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When is an Independent Protection Layer (IPL) Not a Safeguard?

We are going to continue discussing the results from exida’s recently published industry benchmark survey on the practices for the use of alarms as safeguards and IPLs. Over 200 safety practitioners from around the world provided responses. This entry will discuss the relationship between alarms identified as safeguards and…

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How do You Compare?

Industry Benchmark Survey on Alarms as Safeguards and Independent Protection Layers (IPLs)

exida recently conducted an industry benchmark survey on the practices for the use of alarms as safeguards and IPLs. With over 200 safety practitioners from around the world providing responses, you can use the survey findings to…

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The exida Scheme

Today I was asked: “What is the exida Scheme?”  If one person had this question, it is likely that others may be interested as well.  Therefore, I decided to take a moment and explain the exida structure.  Any Certification Body operates each product certification per a “scheme,” which references…

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Root Cause Analysis

Root Cause Analysis - finding out what happens when a failure occurs, and why it happened in the first place.  There are many reasons for root cause analysis.  The “system” design can be improved to prevent some of the failures from happening again and those who troubleshoot can do…

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  • by Dr. William Goble, CFSE
  • Thursday, May 09, 2013
  • Certification

Certificate Forgery!

exida has discovered yet another forged functional safety certificate.  You can read about another occurrence in a previous blog entry.

False Certificate


The company name on the forged certificate is ISP SA DE CV, Cunduacan, Tab., Mex.  How could someone…

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Which Edition of IEC 61508 is Relevant to Me?

Simply stated, the 2nd edition of IEC 61508 is the relevant standard for newly developed products and new certifications.  This represents the current best practices on functional safety techniques and measures, and is what the marketplace expects for today’s products. 

Renewed certifications can use the 1st edition of…

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