Ergonomics in Disaster Analysis and Prevention
What is ergonomics? Generally it means designing things (e.g. tasks, environments, tools) to fit people (e.g. size, strength and cognitive abilities). Recent public attention to ergonomics has been focused on a small portion of the field considering things like office design and chair features. What many of us don’t realize is that ergonomics plays a much larger part in systems, like a nuclear power plant, than just making sure the operator has a comfortable chair to sit in.
In a book titled ‘Set Phasers on Stun’ and Other True Tales of Design, Technology, and Human Error, author Steven Casey presents factual stories of how technological failures have been the result of incompatibilities between design and human perception.
Have you ever seen an airplane cockpit? Or have you seen the newly released film “Pearl Harbor” and been caught up in the adrenaline of an air attack? Add the complexity of airplane controls to the stress of being under attack, and then change the meaning of just about every button and switch in the cockpit and you can start to imagine how one South Pacific stationed pilot felt at that time.
One of the accounts in Set Phasers on Stun is about a US Army Air Corps pilot who nearly lost his life due to design expectations. Pilot Dan Bowman was a little farther away from the parked P-47 Thunderbolts than the rest of the pilots when the air raid siren sounded. Since there were exactly as many planes as pilots, when he reached the airfield most of the other pilots were in the air. There was one plane left, a brand new Thunderbolt. He had never flown in that plane before, but it was the same model as what he was used to so it shouldn’t be any different, he thought.
As he sat down in the plane he realized that it was VERY different. The controls weren’t in the same place, not even the fuel gage could be immediately found. And Dan had to get started immediately as he could see the approaching Zeke fighter bombers.
Stuck on the airstrip Dan surveyed the controls before him, and looked up at the oncoming attack. There was no way that he would be able to get the plane in the air and survive an attack. He spent the next few minutes running along the ground in the Thunderbolt dodging bombs and bullets. He survived the attack and reported the problem to researchers after the end of Word War II. Dan Bowman once commented that he never understood why someone would redesign a fighter plane’s instrument panel in the middle of a war.
Did you catch the ergonomics in that? Maybe something more routine would help. When you drive a car you have expectations of the equipment. For example, when you turn the wheel to the right, the car goes right, or when the left pedal is pushed, the car slows. What if you got into a new car, and were driving and had to quickly dodge some debris. You turned the wheel to the right and the car went to the left crashing into the debris. This scenario is often called ‘human error’. It was the driver’s fault because they did not know how to work in the system. But, what we actually have is a mismatch or poor fit between the environment (car), the task (turning right), and the human (perception that turning wheel right will turn car right). That is ergonomics