I want to share a perfect failure scenario that happened to me and has been happening to me since April 2021. And yes, I see the world through the lens of a safety engineer – hate me for it if you must. The failure is 99% my fault for trusting a simple financial tool via…...
Personal Human Factors Failure experience Read More »
… Membership Required You must be a member to access this content.View Membership LevelsAlready a member? Log in here...
Human Error Decision Matrix Read More »
As my year comes to a close on the railroad, I recently has a discussion with a senior manager about ALARP, a new acronym for the RR. The manager wanted to know more about using the Hierarchy of Controls to reduce risks; more specifically, how we would reduce the SEVERITY of the consequence of an…...
ALARP and Railroading Read More »
In his 2018 book, Risk-Based Thinking – Managing the Uncertainty of Human Error in Operations, Muschara has a passage that hits a home run in how human error is viewed in American society and why this view of human error is so difficult to break through… (p.39)… Membership Required You must be a member to...
The notion of human error (Muschara) Read More »
I am betting most everyone has heard the old phrase, “that’s an accident waiting to happen.” My brother (also a safety engineer) and I have pondered whether our father, who used that phrase often, influenced our career choices more than we had ever imagined. But how many safety professionals understand what this phrase is saying?…...
Ever heard someone say “That’s an accident waiting to happen” Read More »
Although it may be possible to accept that errors are neither as numerous nor as varied as they might first appear, the idea of a predictable error is a much harder one to swallow. If errors were indeed predictable, we would surely take steps to avoid them. Yet they still occur. So what is a…...
Variable and Constant Errors (Dr. James Reason) Read More »
Assigning probability values to errors is still very much an art form. Nonetheless, there is sufficient general agreement about the likelihood of errors occurring in various generic tasks to put them into sensible rank order. Their main use is to provide benchmarks for the range of error probabilities over different jobs.Here is a list of…...
Error Probabilities (Reason Model) Read More »
Unsafe acts are of two (2) distinct types: Errors and Violations Errors arise from informational problems and fall into three categories:… Membership Required You must be a member to access this content.View Membership LevelsAlready a member? Log in here...
Active Failures (Unsafe acts) Read More »
When we were children, adults frequently told us to stop and think—good advice, but they rarely told us what to think about. I have sought to overcome this omission with the ‘three-bucket’ model described below. This model forms the basis of the mental skills designed to impart error wisdom and risk awareness. The buckets correspond…...
The Three-Bucket Model for assessing risky situations (Reason) Read More »
The probability that the total system will perform correctly when it is available is the probability that the hardware/ software will perform correctly, times the probability that the operating environment will not degrade the system operation, and times the probability that the user will perform correctly. By defining the total system this way, human performance…...
Total System Performance Approach to Human Factors (FAA) Read More »
One of the best examples of Human Factors Engineering is seen daily when driving… street signs. We all know a STOP sign when we see one. It may be the most recognized sign in all advanced societies. Did you know that at least 35 countries use a red octagon as their stop sign? But imagine…...
Human Factors 101 – Street Signs Read More »
The skill-based performance involves highly practiced, primarily physical actions in very familiar situations in which there is little conscious monitoring. Such actions are usually executed from memory without significant conscious thought or attention. Behavior is governed by preprogrammed instructions developed by either training or experience and is less dependent upon external conditions. Information that can…...
Human Errors (“Honest Mistakes”) Read More »
