exida explains Blog

Evaluating Alarm System Performance in a Multi-Operator Control Room

Evaluating Alarm System Performance in a Multi-Operator Control Room

Situation: There are three operator consoles (positions) in the same control room. There is one general alarm horn that goes off whenever a new alarm comes in from any one of the three consoles.…

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How Cars Relate to exida’s Site Safety Index (SSI)

How Cars Relate to exida’s Site Safety Index (SSI)

I got a new car.  The process was a bit disturbing. It took over an hour to go through the “set-up” menu. And it was suggested that I return for a second training session after…

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Guest Blog: Thar’s Gold in Them Thar Failure Data

Guest Blog: Thar’s Gold in Them Thar Failure Data

Failure data collection can seem tedious, time consuming and expensive.  Just figuring out what data to collect can be challenging.  Failure data analysis can be overwhelming with a sense of “I don’t even know where to…

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Back to Basics 16 - PFDavg

Back to Basics 16 - PFDavg

PFDavg (the average Probability of Failure on Demand) is the probability that a system will fail dangerously, and not be able to perform its safety function when required. PFDavg can be determined as an…

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Why Does My Risk Assessment Require an FMEDA?

Why Does My Risk Assessment Require an FMEDA?

If you find yourself faced with this question you might be wondering why it is that having successfully used risk assessments without FMEDA your team are suddenly faced with the complexity of…

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PES Refinery – CSB Initial Report

PES Refinery – CSB Initial Report

I'm sure you are aware of the preliminary findings of the Philadelphia Energy Solutions (PES) Refinery explosion. If not, have a look at the video below. It is very interesting, but sad.  I think…

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The Non-Hackable System – Wait a Minute, What?

The Non-Hackable System – Wait a Minute, What?

I had the privilege to attend the CDS-forum in Trondheim, Norway on October 15, 2019. The CDS-forum is a Norwegian Industry Forum for Cybersecurity of Industrial Automation and Control Systems. The forum…

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How Much Testing Is Enough?

How Much Testing Is Enough?

Have you ever wondered if you tested your product enough? Either in enough ways or for a long enough time?  This assumes that you’d prefer to discover all the problems before your customers do.…

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Back to Basics 15 - Architectural Constraints

Back to Basics 15 - Architectural Constraints

Architectural constraints are limitations that are imposed on the hardware selected to implement a safety-instrumented function, regardless of the performance calculated for a subsystem. Architectural constraints are specified (in) according to the required of the…

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My Final Element Field Failure Data says 150 FITS and OREDA is 2000 FITS

My Final Element Field Failure Data says 150 FITS and OREDA is 2000 FITS

I got an email saying that the exida's www.SILSafeData.com minimum failure rates were way too high.  The email went on to say that his REAL field failure data showed a result of 150 FITS…

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Personnel Certification Concerns? We are Here to Help.

Personnel Certification Concerns? We are Here to Help.

A few weeks ago, we were asked to help a fellow colleague who received a message regarding their FS Engineer (TÜV Rheinland) certificate :

We are aware, that the validity of your FS Expert…

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Are Your Control Systems Really Protected?

Are Your Control Systems Really Protected?

Back to Basics 14 - Systematic Capability

Back to Basics 14 - Systematic Capability

Systematic Capability is achieved when the equipment used to implement any safety function is designed using procedures intended to prevent systematic design errors.  The rigor of the required procedure is a function of a Read More...

Let’s Talk About Configuration Management and ISO 26262

Let’s Talk About Configuration Management and ISO 26262

Most software developers are familiar with the need for and benefits of change control. Usually change control means one thing to a software developer and that is 'commits' to a source code revision control…

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Do You Really Know What You Know (When it Comes to Functional Safety)?

Do You Really Know What You Know (When it Comes to Functional Safety)?

You don’t’ really know what you know until you have to explain it (or teach it) to someone else. 

When I’m asked about some of the technical aspects of functional safety, I have…

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