exida explains Blog

What is Systematic vs. Random Capability?
  • by Loren Stewart, CFSE
  • Tuesday, September 01, 2015
  • Certification

What is Systematic vs. Random Capability?

There seems to be a bunch of confusion surrounding systematic capability and random capability.  I will try to clear up the confusion by explaining what is all considered and what the IEC standard says about both. 

Systematic Capability

  • Development process/quality system requirements depend on certification SIL level, higher…

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The Architectural Constraint Blind Side
  • by Denise Chastain Knight, P.E., CFSE, CCPSC
  • Thursday, August 27, 2015
  • Certification

The Architectural Constraint Blind Side

I did my homework, purchased certified devices, and specified physical redundancy. I expected an uneventful SIL Verification but the assessor is telling me that I have functions failing Architectural Constraints in the sensor and final element groups. How can that be? 

Low demand mode Safety Instrumented Function (SIF)…

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Failure Rate Data: Are You Being Outsold?

Failure Rate Data: Are You Being Outsold?

When speaking with several manufacturers’ sales teams recently, it became very evident that some of these sales people, selling into the Industrial Safety and Controls markets, had little or no knowledge of how their products’ failure rate data compared to their competitors and/or another industry benchmark (such as DOW…

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How Cybersecurity is like a Goldfish

How Cybersecurity is like a Goldfish

Oh look! Squirrel!

I am not much of a blogger. I should be but I’m not. This is strange, because I always have plenty to say.

This subject just gets me going so I am writing about it. I welcome feedback and opinions.

I have been in cybersecurity in…

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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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The True Meaning Behind Those Fancy Letters on a Signature

The True Meaning Behind Those Fancy Letters on a Signature

Let me ask you a few questions: Does adding letters after a person’s name make them more important? What did that person go through to achieve those letters? If someone has XYZ after their name and another person also has XYZ after their name, are they equal? Did one…

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Back in the Old Days

Back in the Old Days

Some time ago, I was involved with embedded software projects using microprocessors that had limited memory, speed, and I/O resources.  All embedded programming was in assembly code.  All memory variables were global; it was too hard to keep track of stack variables.  The hardware design assumed that any technical…

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  • by Dr. William Goble, CFSE
  • Tuesday, August 04, 2015
  • Certification

Getting Realistic Failure Rate Data - Part 6

Over the course of several blogs , I talked about getting realistic failure rate data, where this failure data comes from, and how different methods of failure data analysis compare. I think if you understand this, you will begin to get a very good feel of what it takes…

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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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Getting Realistic Failure Rate Data - Part 5

Over the course of several blogs , I will talk about getting realistic failure rate data, where this failure data comes from, and how different methods of failure data analysis compare. I think if you understand this, you will begin to get a very good feel of what it…

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I Did Not Lock the Car Door

I Did Not Lock the Car Door

I was driving one of exida’s top risk experts from Europe to a business meeting. We parked and I locked the car door.  He commented “I noticed you did not lock the car door when you parked at the exida office.” He was right. In an area I do…

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Getting Realistic Failure Rate Data - Part 4

Over the course of several blogs , I will talk about getting realistic failure rate data, where this failure data comes from, and how different methods of failure data analysis compare. I think if you understand this, you will begin to get a very good feel of what it…

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That Could Never Happen! What are the Odds?

That Could Never Happen! What are the Odds?

I often walk through my quiet neighborhood streets on weekday evenings or weekend mornings.  These are the times when I don’t expect much traffic, and my expectations are usually met.  The probability of a dangerous event that would injure me seems pretty low (risk assessment), since I am usually…

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Can Wireless be used in Functional Safety?

Can Wireless be used in Functional Safety?

exida just completed certification of a new sensor product that uses wireless communication to signal a safety logic solver of a potential problem.  Shortly after the certificate was posted, a challenge arose:  “How can wireless be used for safety?”  Well, it is different.  A designer must be fully…

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Performing a Cybersecurity Risk Assessment as a Component of the PHA

There are three main components of the safety lifecycle: analysis, realization, and operation. We will be taking a look at the analysis phase, particularly related to the cyber industry.

To start, the first thing to do in both safety and security is do a detailed process, hazard and…

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