Safe Failure Fraction (SFF) is defined as the ratio of the average rate of safe failures plus dangerous detected failures of the subsystem to the total average failure rate of the subsystem. It is…
Safe Failure Fraction (SFF) is defined as the ratio of the average rate of safe failures plus dangerous detected failures of the subsystem to the total average failure rate of the subsystem. It is…
After careful planning and development of your system, the last thing you want to worry about is the credibility of your certification. Although it may seem like a given for your certification to be…
Route 2H is one of two Architectural constraints options made available in the standards IEC 61508-2 and IEC 61511. Route 1H . Both Route 1H and Route 2H are limitations that impose the hardware selected to implement…
US Chemical Safety Board cites lack of Alarm Philosophy, Alarm Rationalization, and State-Based Alarming as Contributing Factors to Blowout in Oklahoma
On January 22, 2018, a blowout and rig fire…
Route 1H is one of two Architectural constraints options made available in the standards IEC 61508-2 and IEC 61511. Route 1H . Both Route 1H and Route 2H are limitations that impose the hardware selected to…
We all know that an FMEDA is only as good as the assumptions made regarding typical design engineering practices and the database used for the failure rates. Here is the catch, not…
Alarm floods are periods of alarm activity during which the alarm rate is greater than the operator can effectively manage (e.g., when the operator receives ≥10 alarms in 10 minutes). During a flood situation awareness is compromised…
The question of whether companies follow good site safety practices is an interesting one. Firstly, what do we mean by good site safety practices? I think most companies believe they follow good site safety practices but…
New reports out now are claiming that an aging, failed elbow pipe appears to be the initial cause of a June 21 fire and subsequent explosions that injured five people at the largest oil…
PFH (The Probability of Failure on Demand per Hour) is the probability that a system will fail dangerously, and not be able to perform its safety function when required. PFH can be determined as…
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.…
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…
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…
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…
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…