Human Performance and a Rat Trap
The rat trap is a fantastic combination of simplicity and efficiency. There isn’t much to it – just a wood pallet, a coiled spring, a latch, and a bar – but the results are impressive. The rat trap we know today was patented in 1897 and has remained unchanged for over a century for one reason: it works. However, the device comes with its own set of hazards for humans. The kinetic energy stored in the coiled spring is indiscriminate and comes at you in fewer than 0.004 seconds. Despite this, it’s easy to become complacent when handling a rat trap. The original patent called it the “Little Nipper,” which sounds almost harmless. In fact, the term “rat trap” is a little misleading since the intent is not to trap rats but rather to kill them (I guess the name “Rat Spine Snapper” didn’t poll well with focus groups in the 1890s). The rat trap has a job to do, and it does it well, but not without risks. This is also true of many jobs utility safety professionals engage in daily; we do our best to execute them well, but they have their risks.
Just like the rat trap, human performance is a fantastic combination of simplicity and efficiency. It’s all about recognizing the risks we face every day during the course of our work and taking steps to mitigate them. Some risks are easy to identify, but others – like the rat trap – lay in waiting, ready to cause harm. This is how my Knowledge Vine colleagues and I perceive latent organizational weaknesses (LOWs), those hazards we fail to recognize because we have walked by them a hundred times without consequence. These LOWs are similar to the rat trap in that if they are not understood and properly handled, they have the potential to kill you or your performance when activated. A few examples include poorly written procedures, vague or interpretive guidance about performing a task, and the ever-present “you should just know how to do it.”
A Critical Principle
However, techniques are available through human performance to help us recognize and mitigate the hazards associated with our jobs. Like the rat trap, human performance principles have stood the test of time for one reason: they work. One such principle is the critical-step check, which involves recognizing the hazards inherent in a particular job and ensuring the steps we take will produce the desired results. During many tasks, there are specific steps we must perform that are irreversible and can have devastating consequences if executed improperly. We can’t avoid these tasks, but we can work to ensure that everything leading up to our initiating action has been performed in a way that guarantees the outcomes we want. A good analogy is the job of rat trap testing.
Our job today is to ensure that all of the rat traps work before sending them out to the public. What’s the critical step in testing the functionality of a rat trap? Some may argue that it’s when you’re pulling back the hammer or placing the holding bar over it and setting it in the catch. These tasks are reversible. Activating the catch-release is not. If your fingers are in the way when the catch-release is touched, it’s too late. Irreversible harm has happened, and pain is setting in. If you’re the rat, well, you’re dead.
How can we ensure that we will not suffer unwanted consequences when we perform tasks? Simply performing a critical-step check as follows can help reduce painful mistakes:
1. Summarize the critical step. In this case, it’s activating the catch-release on a rat trap.
2. Anticipate error-likely situations. For instance, your fingers are near the hammer strike area; you’re not sure how the catch-release works; there’s no procedure for the work; you’re facing time pressure; you’ve never performed this task before; you’re not trained.
3. Foresee consequences. What could happen or go wrong if we don't mitigate error-like situations? There will be an action; will we get the reaction we want?
4. Evaluate defenses. Ask yourself, what do I have available to prevent an unwanted consequence? What else do I need to do to be successful? Am I using my hand and eye protection? Can I set the rat trap in a vise to get my fingers out of the way? What tool can I use to initiate the catch-release?
Additional human performance behaviors may also help, such as self-checking, peer checking, and demonstrating a questioning attitude. Once these behaviors become true standards, it’s easy to see how we can avoid the trap of initiating a critical step without evaluating our actions' irreversible results. When used correctly, human performance methods are simple and efficient and will help us all perform our jobs more safely.