exida explains Blog

Entries tagged with: IEC 61508

Back to Basics: Failure Rates - λD

Back to Basics: Failure Rates - λD

The Greek symbol  λD represents dangerous failure rates in functional safety, usually expressed in the unit of measurement of FITs, and can be determined through FMEDAs. (FITs (λ) are failures per billion hours, expressed by 10-9 hours).

λD is the number of dangerous failures per…

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Back to Basics: Failure Rates - λDU

Back to Basics: Failure Rates - λDU

The Greek symbol  λDU is the undetectable dangerous failure rate in functional safety expressed in the unit of measurement of FITs which can be determined through FMEDAs. (FITs (λ) are failures per billion hours, expressed by 10-9 hours).

λDU is the number of dangerous undetected failures…

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Building a Foundation for an IEC 61508 Development Process

Building a Foundation for an IEC 61508 Development Process

There are organizations that are small enough to follow an informal or even undocumented process and still produce a product of sufficient quality to meet market needs.  When these organizations attempt to develop a safety product, they inevitably fall short of meeting the requirements of IEC 61508.  A formalized…

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  • by Dr. William Goble, CFSE
  • Thursday, May 12, 2011
  • Certification

Buy Certified Equipment, Meet the Standard, Right? WRONG!

  • 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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Certification and the Environmental Test
  • by John Yozallinas, CFSE
  • Tuesday, August 18, 2015
  • Certification

Certification and the Environmental Test

Functional Safety Assessments (FSA) focus on the relevant functional safety standards that are to be applied to a product in the appropriate industry.  These are standards such as IEC 61511 in the process automation industry, or ISO 26262 in the automotive industry.  And IEC 61508 is like an umbrella…

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Certified to SIL 4 - Cycle Test Failure Data is Dangerous

I got a copy of the IEC 61508 certificate for a solenoid valve today from an engineer who thought something was wrong.  Although the certificate was from a well known certification company, the certificate gave a “Dangerous Failure Rate” of 1.7 FITS (1.7 * 10-9 failures per…

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  • by Ted Stewart, CFSP, exidaCSP
  • Friday, January 30, 2015
  • Certification

CFSE/CFSP: Why and How to Become One

 

As an engineer responsible for critical industrial processes, we face a variety of challenges:

  • coping with new and changing standards
  • increased pressures for process uptime and plant safety
  • a growing list of responsibilities
  • decreased availability of support personnel

This makes…

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  • by Iwan van Beurden, CFSE
  • Thursday, March 21, 2013
  • Software

Changing the PVST Interval. Hey, my Architectural Constraints changed!

Comparing the IEC 62443 Software Engineering Process to IEC 61508: Where Do They Overlap?

Comparing the IEC 62443 Software Engineering Process to IEC 61508: Where Do They Overlap?

With the appearance of malware and nation state attacks on Industrial Control Systems (ICS), such as the Stuxnet (2010), Industroyer (2016) and TRITON (2017) attacks, the IEC 62433 standards are gaining wider attention.  

While the potential targets to attack in an ICS system are many-fold, one plant asset that…

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  • by Dr. William Goble, CFSE
  • Tuesday, March 08, 2011
  • Certification

Counterfeit Certificate!

I am told that plagiarism is a compliment. Since exida is the leading company for IEC 61508 certifications I suppose it was bound to happen. Well it did. exida got an email from our sales representative in China. He asked why this certificate was not listed on the…

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  • by John Yozallinas, CFSE
  • Thursday, December 12, 2013
  • Certification

Developing a Functional Safety Product: What You Need to Know

Thinking about developing a safety product?  Use these 3 steps as a starting point:

1. Know thyself

Do you have documented development processes that govern how you develop a product from start to finish?  If not, start by writing down what is actually being done.  Interview the people…

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Do you know your Site Safety Index?
  • by John Yozallinas, CFSE
  • Thursday, August 02, 2018
  • Certification

Do you know your Site Safety Index?

There’s a lot that exida does behind the scenes to advance the industry and benefit you. We try to make sense of data that we collect and put it to good use. One thing we found is that human activities play a role in functional safety, often causing the intended safety performance…

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Dreaming of a Better Tomorrow?

Dreaming of a Better Tomorrow?

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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Elektrobit Automotive EB tresos® Safety OS 2.x for TriCore TC29xT

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Fake Fact: Final Elements should not be included in SIF evaluation

Fake Fact: Final Elements should not be included in SIF evaluation

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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Fake Fact: IEC 61508 Does Not Affect Me As an End User

Fake Fact: IEC 61508 Does Not Affect Me As an End User

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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Field Data Validation with Predictive Analytics

Who cares about field failure data? Why are we even here?

IEC 61511 – Fundamental Concepts

The fundamental concepts from our functional safety standards are the probabilistic performance based design.  Many of you know that this was terribly controversial when this was first proposed. Even to this day, there…

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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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Fisher Controls

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