exida explains Blog

Welcome to the 2H Initiative

exida has been gathering field failure data for over a decade.  At this point we have a total of over 60 billion unit operating hours of field data for process industry devices.  This data has been used to create a 2H database for components.  exida is using this component…

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  • by Dr. William Goble, CFSE
  • Wednesday, February 27, 2013
  • Software

The Real PFDavg Variables

I was recently asked how the PFDavg value in an exida FMEDA report was calculated. Those PFDavg values are calculated using the exSILentiaTM program. The person who posed the question was using the equations from Part 6 of IEC 61508 and got a different value. Why?

exSILentia

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  • by Ted Stewart, CFSP, exidaCSP
  • Friday, February 22, 2013
  • Certification

Why Personnel Functional Safety Certification Programs are Needed

The publication of the international functional safety standards IEC 61508 (1999), IEC 61511 / ISA-84 (2004) and IEC 62061 (2005) were significant milestones in the effort to increase equipment and process safety. 1,2,3  Unfortunately, the release of safety standards does not by itself make the world a safer place.…

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  • by John Yozallinas, CFSE
  • Tuesday, February 19, 2013
  • Certification

It’s Just a Little Change…

Once there was a laundry room with old, worn-out linoleum floor.  It was functional but did not have the look and feel of newer homes.  The lady of the house decided to replace the flooring with new ceramic tile.  She engaged her husband with the idea, outlining the benefits…

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Stiction: Fact or Fiction & Start Time Prediction

How Does Stiction Affect Me?

What is Stiction?

Many studies and organizations have defined stiction, or static friction, in different ways. A few examples of the various definitions are as follows:

  • According to Entech [1], “stiction is a tendency to stick-slip due to high static friction. The phenomenon causes a limited resolution of the resulting…

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  • by Chris O'Brien, CFSE
  • Tuesday, February 05, 2013
  • Software

How Do You Handle Interposing Relays?

Many times in the design of a safety instrumented system it is necessary to utilize an interposing relay. Typically there is not a certified relay available. Since no certified product is being used it is important to follow the requirements to justify prior use and also to design…

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New Working Group (WG7) Formed for Alarm Management

The ISA-18.2 committee on alarm management has launched a new working group (WG7) that is focused on developing a standard, recommended practice, or technical report on the application of alarm management to process plants utilizing multiple packaged equipment systems. The work will be based on and complement the existing…

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Understanding Our Customers – One Step Closer to Excellence

Customer service isn’t about slashing prices or offering great rates.  Sure these types of strategies can promote new customers and generate business, but how often do the “new customers” return if the service or product didn’t meet their expectations?  It’s always said that a great sales person can sell…

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2012 - Good Progress for Cybersecurity and Functional Safety

I think it is wise for individuals to periodically review things. I like to do my professional review at the end of the year. 2012 was a good year.

Product Certification

Over 60 new products received functional safety or cybersecurity certification this year. Those products and more…

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Replace Before Failure

The solenoid valve manufacturer provides an FMEDA report that lists “useful life = 12 years.”  Useful life is a reliability engineering term that indicates a point in time when the failure rate of a device will begin increasing rather rapidly.  Why do we care about this time interval?  That…

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  • by John Yozallinas, CFSE
  • Thursday, December 06, 2012
  • Software

Spaces and Braces and Comments – Oh My!

What constitutes a good coding guideline?

Serious software development for functional safety requires a coding standard or coding guideline. Most organizations have one, but how do you know if it’s good?

You need to look beyond the boilerplate and physical code layout that are often defined in a coding…

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  • by Michael Medoff , CFSE, CISA
  • Thursday, November 29, 2012
  • Certification

Tool Qualification and Safety Standards

When building a product such as an anti-lock braking system for an automobile, or a railroad, or process control safety system, making sure that the product works as specified is a big part of functional safety. When it is time for the system to engage to prevent an accident,…

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Alarm Rationalization is “Going Green (field)”

With the growing adoption of the ISA-18.2 standard on alarm management, industry leaders are increasingly implementing alarm management best practices (such as alarm rationalization) during the upfront design, before they start up control systems for new, “Greenfield” installation. There are numerous benefits. You think alarm overload and nuisance alarms…

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