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World Cup Fever & Failure Rates

World Cup Fever & Failure Rates

Do you have World Cup Fever? Well I do. Especially after the Netherlands (Holland) beat Spain 5-1 on Friday. I wished that was the score last time they played. So what does this have to do with failure rates? Sometimes my mind works in odd ways. While driving home…

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How Secure Are Your SIS, BPCS, and/or SCADA Systems?

How Secure Are Your SIS, BPCS, and/or SCADA Systems?

As an end-user, do you know how reliable and safe your Safety Instrumented Systems (SIS) and Basic Process Control Systems (BPCS) are from potential cyber issues?  Do you rely on your vendor statements regarding the robustness of their products?  If the answer to these questions is “don’t know”…

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You Need a Checklist!

You Need a Checklist!

At least I do.  Sometimes I wonder how I could forget certain things.  Maybe it’s age? Maybe it’s information overload?  It’s always apparent when I get ready to go on vacation.  You’ve probably been in the same situation… arriving at your destination only to find that the one thing…

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Random vs. Systematic?
  • by Dr. William Goble, CFSE
  • Wednesday, May 07, 2014
  • Certification

Random vs. Systematic?

Most of you know that exida gathers field failure data from many sources including manufacturers’ warranty return data and end user maintenance/failure records.  At this point we have nearly 100 billion unit operating hours of data.  This is probably the largest process industry data set in the world.  And…

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Still Using Excel to do PFD Calculations?
  • by Steve Gandy, CFSP
  • Monday, April 28, 2014
  • Software

Still Using Excel to do PFD Calculations?

It’s very interesting to me to find that people are still using excel to do PFD calculations.  Whereas this is probably okay for simple single element architectures (i.e. single sensor, single logic solver and single final element), it becomes extremely complicated when dealing with redundant architectures.  Moreover, for performing…

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Are You Building a Safer World?

Are You Building a Safer World?

Every man takes care that his neighbor shall not cheat him. But a day comes when he begins to care that he does not cheat his neighbor. Then all goes well.”  - Ralph Waldo Emerson

I like to think about functional safety in a similar way.  We all want…

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I Know My Requirements. Now What?

I Know My Requirements. Now What?

If you’ve written your new product requirements, you probably understand exactly what they mean.  But will the other people on your project team?  You also probably understand that some unwritten requirements must also be met. They’re just common sense and everyone knows what they are. 

What about that new…

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Cycle Testing for Static Applications? NO!

Cycle Testing for Static Applications? NO!

The failure rates of certain mechanical components used in solenoid valves, actuators, and valves vary substantially depending on operation. Seals such as O-rings, for example have fundamentally different failure modes when used in applications with frequent movement (dynamic) versus applications with infrequent movement (static). 

Static is generally…

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What is a “House Certificate?”
  • by Dr. William Goble, CFSE
  • Tuesday, March 11, 2014
  • Certification

What is a “House Certificate?”

exida was recently auditing a systems level project per IEC 61511.  During such audits we check to verify that all equipment used in a safety instrumented function meets systematic capability by either IEC 61508 certification OR justification per reasonable IEC 61511 “prior use” criteria.  Most engineers at…

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The Problem with the Expert
  • by Dr. William Goble, CFSE
  • Wednesday, March 05, 2014
  • Certification

The Problem with the Expert

I recall the first time I was called an “expert.”  I thought that sounded nice. I spotted a magazine article on safety and thought “I do not have to read that as I am an expert.” I quickly recovered.  The real problem with being called an expert is that…

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Ten Years Later
  • by Steve Gandy, CFSP
  • Wednesday, February 19, 2014
  • Certification

Ten Years Later

It’s hard to believe that the IEC61511 standard has been in existence since 2003, and most companies operating in the process, chemical, and refining industries (or any other hazardous process manufacturer) have adopted its practices.  It’s also significant that any plants that were built back then with a…

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A Bug (Free) Life

A Bug (Free) Life

Can we really ship a bug-free product? That’s a tough question to answer.  Bugs originate in many places and not all bugs are the same severity.  But you can’t control what you don’t measure.  If you log and classify defects, and control the way changes are made, there may…

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Dare to Be Different

Dare to Be Different

Product Stewardship and Engineering Ethics

Product Stewardship and Engineering Ethics

Recently I witnessed something I never thought I would in the engineering profession: I was told by a system designer that even though they knew the safety reliability data for one device was too optimistic, they were going to use it because it meant they didn’t need to…

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Functional Safety, Cybersecurity, and Alarm Management in 2013
  • by Dr. William Goble, CFSE
  • Friday, January 10, 2014
  • Certification

Functional Safety, Cybersecurity, and Alarm Management in 2013

2013 was a good year for functional safety progress.  exida Certification issued a record number of new product functional safety certifications in mostly every product category - valves, actuators, solenoid valves, PLCs, fire and gas sensors, process sensors, and components.  The component category is one of the most…

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