exida explains Blog

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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Todd Stauffer, Director of Alarm Management at exida, takes you through a key part of the Alarm Rationalization process called Alarm Objective Analysis (AOA).

You will learn how to determine what alarms you need (and which one’s you don’t), how to eliminate nuisance alarms, and safely reduce the number…

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Look at the picture. What do you see? I see a spring return actuator with

• a diaphragm chamber
• a spring chamber
• the scotch-yoke mechanism

What are the high level potential failures for a ball valve?

• Scotch-yoke mechanism breaks, can no longer operate valve…

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Look at the photo. What do you see? I see a ball valve with:

• a valve body
• a ball
• a stem that can turn the ball

What are the high level potential failures for a ball valve?

• Stem stuck, can no longer turn (dangerous)
…

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ICS cybersecurity standards such as ISA 62443 (formerly ISA 99) and NERC CIP require operators to have policies and procedures in place to monitor and maintain their critical ICS cyber assets.  For anything other than very small systems, the obvious choice is to implement systems…

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The world of automation has changed significantly over the past 30 years.  I have fond memories of starting my career by calibrating, adjusting, and tuning pneumatic control loops while working my way through the electronic age right up to the present digital and cyber generation of automation.  If you…

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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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Please see the first entry of the Requirements Management blog series here.

The concepts of allocation and derivation are sometimes misunderstood when it comes to requirements management.  This can lead to confusion and even to safety problems.  The process of derivation involves the writing of a new requirement, …

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How many development teams have heard those few, innocent words uttered from Marketing/Management toward the end of the development phase of a project, only to have their schedule blown out of the water?  The phase of development into which the change is introduced determines the size of the concentric…

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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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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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Formalize your process.

Companies often have a pretty good hardware development process in place, dealing with electrical and mechanical drawings, bills of material, and the factory floor interface.  Most of these processes are in place so the manufacturing department knows what to make and how to put it together. …

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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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IEC 61508 and IEC 61511 are known as “performance” based standards.  Specific design rules, as found in “prescriptive” standards, are not included, allowing for innovation and new technology, as well as creativity and advancement.  However, it does imply that a certain level of competency is required.

Others would strongly…

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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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