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Dr. William Goble, CFSE

Can Wireless be used in Functional Safety?

Monday, June 29, 2015 | Functional Safety | Feed


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 aware of the different time response issues. The system must be configured to fail-safely upon loss of the wireless signal.  The system timeout must be long enough to deal with the redundancy of radio media.  But it is safe.  The protocols have been through careful analysis and will provide a safe message when the signal is good. 

“But what about security? I do not…

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Dave Johnson

Performing a Cybersecurity Risk Assessment as a Component of the PHA

Tuesday, June 16, 2015 | Industrial Control System (ICS) Cybersecurity | Feed


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 risk analysis of the system. In the case of safety, you should allocate safety functions that will protect against those risks that you have identified and create a safety specification or set of requirements for each of those safety functions that you are going to apply. Once those requirements are in place, the realization phase is similar to other realization efforts, including design and engineering, acceptance testing and installation, and…

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Dr. William Goble, CFSE

Getting Realistic Failure Rate Data - Part 3

Wednesday, June 10, 2015 | Functional Safety | Feed


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 takes to generate realistic failure data. This is a subject I find very important and I hope you will find your time well spent reading this.

In Part 1,  I wrote about the fundamental concepts of functional safety standard for the process industries, IEC 61511. As well as the design phase of the safety lifecycle. In this blog, I will continue with talking about two fundamental techniques that have been developed…

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Michael Medoff , CFSE, CISA

The Evolution of Coding Standards

Monday, June 08, 2015 | Functional Safety | Feed


Sometimes it seems that things change slowly in the world of functional safety.  If you look at many of the technical references in IEC 61508 you will find that most come from the 1980s and 1990s.  There is even one reference that dates back to 1950!  With the rate technology is moving, the relevance of such old documents often comes into question.  The topic of programming languages is one area where change is constant, and a good example of this is C++11.  This latest version of C++ is already several years old, but it is starting to become important for functional safety.  The C and C++ languages have long been known for their…

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Dr. William Goble, CFSE

Getting Realistic Failure Rate Data - Part 2

Thursday, June 04, 2015 | Functional Safety | Feed


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 takes to generate realistic failure data. This is a subject I find very important and I hope you will find your time well spent reading this.  

In Part 1,  I wrote about the fundamental concepts of functional safety standard for the process industries, IEC 61511. As well as the design phase of the safety lifecycle.

In this blog, I will continue with talking about two fundamental techniques that have…

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Dr. William Goble, CFSE

Getting Realistic Failure Rate Data - Part 1

Monday, June 01, 2015 | Functional Safety | Feed


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 takes to generate realistic failure data. This is a subject I find very important and I hope you will find your time well spent reading this. 

IEC 61511 – Fundamental Concepts

IEC 61511 is the functional safety standard for the process industries.  When I read through IEC 61511, IEC 61508 , and the entire family of functional safety documents, I find that there are two fundamental concepts.

The first is…

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Denise Chastain Knight, P.E., CFSE

Close Enough? Not so Much

Wednesday, May 27, 2015 | Functional Safety | Feed


Performing a SIL Verification calculation on preliminary design information can be a very useful tool to dial in the Safety Instrumented Function (SIF), Safety Requirements Specification (SRS) content , and define critical elements for the field component purchase specifications. Conceptual verification is typically performed quickly with general design information. The objective is to gain confidence that the planned design will meet SIL target after detailed specification and procurement. Generalized suppositions are adequate for screening in many situations; however, there are circumstances where preliminary assumptions are not “close enough” to avoid last minute rework in order to achieve final verification. A savvy engineer learns how to adjust assumption to evade the “not so much”…

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Iwan van Beurden, CFSE

LOPAx™: This is Awesome!

Thursday, April 30, 2015 | Software | Feed


LOPAx

You will probably not hear me sing the LEGO® Movie’s “Everything is Awesome” song, I’ll keep that private (and you should be thankful to me for that). However as we just released the LOPAx™ module of the new exSILentia® v4 platform, I have come to the conclusion that what we have built here is, maybe even beyond, awesome.

As I was working on a new application exercise for our update functional safety engineering training course offering, FSE 101: Safety System Analysis, I wanted to include a HAZOP and LOPA example in that exercise for students to work on. As I’m writing the exercise, I’m working on the solution at…

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John Yozallinas, CFSE

Competency: Cutting Corners?

Wednesday, April 01, 2015 | Certification | Feed


Let’s turn our attention to home remodeling projects for a minute… literally cutting corners.

Most people are familiar with trim molding (baseboard and chair rail).  Laying out the trim on long flat surfaces is pretty easy: measure, cut, nail, paint… done.  Ok, sometimes it goes: measure, cut, measure again, cut the right length this time, nail, paint… done.  Some basic skills with woodworking tools are probably sufficient, but almost every room has corners.  Fitting the trim properly requires you to cut the trim at the appropriate angle.  A typical 90-degree corner is seldom a perfect 90 degrees.  The angle will vary slightly based on what kind of day your contractor is having.  You…

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John Yozallinas, CFSE

Texas City Refinery Explosion: Ten Years Later

Thursday, March 26, 2015 | Functional Safety | Feed


This week marks the 10th anniversary of the Texas City Refinery Explosion.  Is it any safer to work in the oil refinery industry since then?  That’s not an easy question to answer.  It’s difficult to get a yardstick out to measure safety.  But if we consider the number of deaths in the 10 years before the Texas City event and 10 years after, it is not much different: 64 vs 58 respectively.  Even counting deaths and injuries proved challenging due to a number of reasons: contract workers vs. employees, process safety vs. personal safety, counting methods by government vs. manufacturers, according to research by The Texas Tribune and the Houston Chronicle.

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Denise Chastain Knight, P.E., CFSE

Challenge the LOPA - 10th anniversary of the BP Texas City Refinery explosion

Tuesday, March 24, 2015 | Functional Safety | Feed


On the 10th anniversary of the BP Texas City Refinery explosion, let’s pause to reflect on one of the lessons learned from this disaster. The process had multiple layers of protection, including operating procedures, BPCS control and alarms, independent alarms, and relief devices.  There was additional instrumentation downstream that could have identified the scenario. Operator action was required for shut-down. The process design apparently included multiple layers of protection, yet there were sufficient failures to allow a major event to occur.

A Layer of Protection Analysis (LOPA) is intended to verify the independence and suitability of layers of protection, yet incident investigations often reveal Independent Protection Layer…

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Steve Gandy, CFSP

What is Competency Anyway?

Friday, March 13, 2015 | Certification | Feed


What is Competency Anyway?

I’ve been following some discussions from one of the online forums regarding competency and it’s clear from the correspondence that the issue of competency is still very subjective.  It made me think about “what is competency?” To me it’s a blend of knowledge and experience and just how well this knowledge and experience is applied to the task in-hand. 

Some of the correspondence from the forum related to the definition of competency and the fact that the standards (IEC 61508 & IEC 61511) don’t define what competency means.  Some people were arguing that the standard should spell out exactly what’s required, whereas others argued that…

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Iwan van Beurden, CFSE

Using the PHAx™ Libraries

Thursday, February 26, 2015 | Software | Feed


Conducting a Process Hazard Analysis (PHA) can be quite laborious. In a HAZOP, you will systematically evaluate the applicable deviations for each node, within each unit, within each plant. The exSILentia® v4 PHAx™ module is setup to use smart deviations which will be defined for a particular node evaluation based on the node type specified. This will ensure that you are focusing on only those deviations that are applicable for a specific node type.

When you identify potential causes leading to the deviation under consideration, as well as the associated consequence you will enjoy the use of autocomplete functionality where PHA software will automatically suggest a cause or…

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Todd Stauffer

Help Your Operators Defeat the Situation Awareness Demons!

Tuesday, February 17, 2015 | Alarm Management | Feed


Contrary to what you might have guessed, the “Defeat of the Situation Awareness Demons” is not a new video game on XBOX or Playstation. It is a set of eight (8) factors which undermine effective Situation Awareness. It can be applied to operators in process plants to characterize human error when responding to alarms.

But first a bit about Situation Awareness. It originates from the study of human factors in the airline industry (how pilots respond to flight emergencies and comprehend all the gauges, knobs, and switches in the cockpit). Situation Awareness (SA) can be defined as “being aware of what is happening around you, and understanding what that information means to you…

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Ted Stewart, CFSP

CFSE/CFSP: Why and How to Become One

Friday, January 30, 2015 | Certification | Feed


 

As an engineer responsible for critical industrial processes, we face a variety of challenges:

  • coping with new and changing standards
  • increased pressures for process uptime and plant safety
  • a growing list of responsibilities
  • decreased availability of support personnel

This makes it difficult to develop, maintain, and document the expertise needed to excel at our job. A lot companies have even been driven to run leaner operations and optimize performance.  

Company awareness

Company awareness can help reduce the risk for catastrophic safety-related accidents potentially saving them millions. Consequently, it is more important than ever to have competent personnel in safety system…

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