According to numerous industry studies, significant improvement has been made over the last 20 -30 years in occupational safety, but not so much in operational safety (process safety). New process safety incidents continue to occur that bear a striking resemblance to previous incidents. This means we are not effectively learning…
This is a topic which comes up time and again, especially when reviewing legacy systems. Although IEC61511 doesn’t preclude the use of shared devices, it does however provide guidance under Clause 11 of what the constraints are. Even though the Safety Instrumented System (SIS) and Basic Process Control System (BPCS)…
Insurance Companies are hedging their bets through premiums while the Manufacturing Industry is placing their wagers on luck.
The worlds of gambling and insurance are similar in many ways. Both are built upon elements of probability, modeling and quantification of risk. Professional gamblers are well informed on the odds…
It’s interesting that the majority of the time when people talk about functional safety, they are usually thinking about hardware: what sensors to use, which logic solver, what actuator, solenoid or valve to select; what voting architecture, etc. What often gets overlooked, initially, is the application program.
Essentially, when…
Both Process Safety Analysis (PHA) and Layer of Protection Analysis (LOPA) occur in the early stage of the Functional Safety Lifecycle, detailed in both IEC 61511 and IEC 61508. They both serve significant roles in the whole process safety management. Yet, as a facilitator…
Experience is a good teacher. But how do you get the experience?
Formal classroom or online training is often available for more general skills, but on-the-job training usually provides a more in-depth path to gain such experience. After doing a job for a while, working through difficulties with colleagues,…
I can't begin to tell you how many of our customers share with us how lucky they have been to be incident-free at their plant.
Or, because they have not had an incident in over 10 years, it is hard to justify the cost of a Machine Hazard…
The Greek symbol λS represents safe or spurious failure rates in functional safety expressed in the unit of measurement of FITs which can be determined through FMEDAs. (FITs (λ) are failures per billion hours, expressed by 10-9 hours).
λS is the number of safe…
Most end users I teach in our FSE100 class are not really aware of or fully, understand when we talk about failure rates. For example, what’s a FIT mean? For those end users more versed in this, they understand what is meant by a FIT. Essentially a device can have…
“…there is a belief amongst many engineers and managers that human error is both inevitable and unpredictable.
However, human error is inevitable only if people are placed in situations that emphasize human weaknesses and that do not support human strengths”
Martin Anderson, IChemE Safety and Loss Prevention…
In recent discussions with several engineering and integrators of Safety Instrumented Systems (SIS), it’s become very clear to me that the majority I have spoken to, don’t have any form of Functional Safety Management System (FSMS) in place. This is interesting because one of the changes in the…
When we first invented the FMEDA technique in the late 1980s the biggest problem was the component failure rate and failure mode data. Still is. I picked up a well-known standard for component failure rates and saw a date of 2010. The technology world has gone through an order of…
The Greek symbol λDD is the detectable dangerous failure rate in functional safety expressed in the unit of measurement of FITs which can be determined through FMEDAs. (FITs (λ) are failures per billion hours, expressed by 10-9 hours).
λDD is the number of…
I just read a great article in the May issue of IEEE Spectrum magazine called “Managing Risk and Responsibility During a Crisis.” The author Robert N. Charette says “If the American people desire the federal government to be their risk manager of first resort, then an open and…
When it comes to IEC61511 and the selection of equipment for use within Safety Instrumented Systems (SIS) and Safety Instrumented Functions (SIF), there are only two methods that can be used to justify selection: IEC61508 Certified devices for the required SIL or Prior Use Justification. Just…