exida explains Blog

It’s an interesting question and one I asked myself.  For any engineer and/or professional working in the controls business or process industries where safety-related equipment is required, it is essential (per IEC61511-1 Clause 5.2.2: Organization and Resources) to prove competency to carry out any safety-lifecycle activities.  So what does…

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A question was posed to me this week about why the OREDA failure rate for a solenoid valve was greater than the Failure Modes, Effects, and Diagnostic Analysis (FMEDA) results from exida for a specific manufacturer’s solenoid valve.  The person asking the question was clearly challenging the exida…

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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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Mechanical CAD and electronic schematic capture tools have been around much longer than graphical software tools.  This is primarily because physical objects are more naturally represented as components in a computer-aided design program, and it was more obvious how to design those technologies at the time. The “soft” in…

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Part 1 of this blog entry discussed software modeling, modeling notation, and modeling tools. But, what does this have to do with Functional Safety?  The IEC 61508 standard has requirements, for certain SIL levels, regarding the use of:

• “Semi-formal methods”
• Computer-aided specification and design tools
• Design standards
• Performance modeling
…

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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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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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At exida, we just finished a Failure Modes and Effects Analysis (FMEA) on a medical ventilator. This was done for a new manufacturer who needed independent design verification.  It was a fascinating job.  We found lots of pneumatic devices very similar if not identical to the kind used in…

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The V-model is a lifecycle model useful in the product development process that shows the link between the test specifications at each phase of development.  Simply put, it looks like this:

The name comes from the basic shape of the model. …

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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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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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I have run into this question a couple of times now and though the answer is somewhat straightforward, some customers have trouble wrapping their head around this without a clear example. So here we go…

First of all we need to keep in mind that the objective of a…

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In a marketplace where many of buyers of firmly committed to “proven in use,” many projects are still using 30 year-old logic solver designs.  Proven in use is a valuable concept especially for field equipment where it is hard to evaluate how well a product design will…

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