The causal model created by Heinrich in the early fifties, which stated that 85% of all accidents are the result of unsafe workers, has caused decision makers for years to make the wrong decisions. You see, Real Safety starts with engineering and design, not with the user of a piece of machinery and equipment. Once again, you have to think SafetythroughdesignTM.
There was a human factors engineer that came along in the 1980's whose name was Alfonso Chapannis. He said that in their work, human factors engineers have found that there are many man machine systems that are error provocative or "error producing." Whatever it's called an error-provocative situation is one that almost literally invites people to commit errors.
Let me give you an example: You have a computer with WindowsTM on it and you know that on the top of the screen there is a dash, a square and an "X". So you take your mouse and you hurriedly move up to the top of the screen to click on that square to maximize the page on the screen and instead of hitting that square you hit the "X." Instead of maximizing the page, you delete it and you lose two hours worth of work that you've been working on. Have you ever done that? Is that error provocative? Did you say to yourself, "why did I do that? I shouldn't have done that! I knew better than to do that!"
Now if you look at a SafetythroughdesignTM approach you might do what Bill Gates has done on the computer by designing the machine to ask, "Are you sure you want to do this?" The designer could have located the "X" on the left hand side of the screen so that when the user goes up to the upper right corner to click on the square to do the maximizing, he will not inadvertently hit the "X". Now these are examples of Safety through Design.
Unfortunately, there are a lot of machines in America that are built just like this computer example, except that when the operator inadvertently makes a mistake, he doesn't just lose the data he has been working on for the last two hours. Instead he loses an eye, or a finger, or a limb or a life. Or maybe he becomes a paraplegic or a quadraplegic for life.
Chapannis went on to say there are three axioms that follow the notion of error provocative machines. First of all accidents are multiply determined. Any particular accident can be characterized by the combined existence of a number of events and circumstances."
There is a fallacy in the thinking of a number of design engineers. They believe that safety is only the responsibility of the user. Designers and engineers often say that safety is not their job; machine function is their job. This thinking is wrong. You see engineers and designers of machinery have to think SafetythroughdesignTM.
Chapannis said there is a second axiom. He says that given a population of human beings with known characteristics, it is possible to design tools, appliances and equipment that best match their capacities, limitations and weaknesses." So when reviewing incidents, you need to make a deeper analysis than just asking questions related to "what did the user do wrong?" You need to think about SafetythroughdesignTM.
His third axiom states that the improvement in system performance that can be realized from the redesign of equipment is usually greater than the gains that can be realized from the selection and training of personnel. He is not saying employees should not be carefully selected and trained, but he is saying that if equipment can be redesigned to work safely no matter who you put to work on it, workplace safety and productivity will be significantly better. In trying to relate to this concept, think of all the times you have performed an unintentional action and then said, "Why did I do that?" You have to think SafetythroughdesignTM.
An employee slips on a floor hurrying into a meeting. If you investigate this incident and are thinking about what the worker did wrong, you will probably see an Employer's First Report of Injury that says "Employee cautioned not to hurry. He has been told to slow down and be careful so that this will not happen again."
On the other hand if you're thinking about the possibility of there being an unsafe design, what you'd start doing is asking questions like, "Why isn't the coefficient of friction between the bottom of the man's shoe and the floor greater than 0.5?" "Was there a banana peeling on the floor? Did the janitor wax the floor last night with a slippery wax, instead of the non-slip wax we've been specifying for years? Did the architect specify the wrong tile? Or, did the air conditioning vent drip condensation on the floor and there was water on the floor that the worker did not see?"
There is an old Chinese proverb that says "when one falls it is not necessarily one's foot to blame." You have to think SafetythroughdesignTM and quit assuming that a work place injury is always the injured worker's fault.
An employee is injured when he removes the guard on a V-belt drive and is greasing the machine while it is running. Now if OSHA investigates a guard removal case that results in an injury while the machine was running, they are going to fine the employer for failing to Lock Out and Tag Out the machine. And the employee is going to be in trouble too, because he is supposed to perform the Lock Out Tag Out. In that situation you will never find a subrogation case because you're thinking about that "unsafe act". On the other hand, if you are thinking about the design, you would conclude that it would be real simple to just extend the grease fitting through the guard so the operator could put the grease gun on it without ever having to take the guard off? If that is the case, could there be a design problem? You have to think SafetythroughdesignTM.
A car is designed with an emergency brake handle right beside the hood release and the hood pops up when you try to release the emergency brake because you pulled the wrong handle. Is that error provocative? I think so. If you start looking, there are lots of examples around you every day that literally invite you to make mistakes.
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