A very important part in the JHA development process is to discover the hazards lurking within each step. A basic safety concept must be understood by all safety staff: to have an accident, a hazard and exposure to the hazard must exist.
- A hazard is an unsafe condition that could cause injury or illness to an employee.
- Exposure usually refers to an employee’s placement relative to the hazard’s “danger zone”. If the employee is within the danger zone, the employee is exposed.
A job hazard analysis is an exercise in detective work. Your goal is to discover the following:
- What can go wrong?
- What are the consequences?
- How could the hazard arise?
- What are other contributing factors?
- How likely is it that the hazard will occur?
To make your JHA useful, document the answers to these questions in a consistent manner. Describing a hazard by answering the questions above ensures you target the most important contributors to the hazard. The hazard column in your JHA should identify the hazards, and the potential for exposure to hazards.
Rarely is an accident a simple case of one single event or cause. More frequently, many contributing events tend to line up to cause hazardous conditions and unsafe behaviors. Here is an example of a hazard scenario that illustrates this idea:
Now, let’s pretend the accident didn’t happen and it was your job to identify the hazards and exposure inherent in this job. Let’s ask the questions:
- What can go wrong? The worker’s hand could come into contact with a rotating object that “catches” it and pulls it into the machine.
- What are the consequences? The worker could receive a severe or fatal injury.
- How could it happen? The accident could happen as a result of the worker trying to clear a snag during operations or as part of a maintenance activity while the conveyor is operating. Obviously, this hazard scenario could not occur if the conveyor is not rotating.
- What are other contributing factors? The hazards and exposure related to this job can occur very quickly. It does not give the worker much opportunity to recover or prevent it once his hand comes into contact with the rotating rollers. This is an important factor, because it helps you determine the severity and likelihood of an accident when selecting appropriate hazard controls. Unfortunately, experience has shown that training is not very effective in hazard control when triggering events happen quickly because humans can react only so quickly.
- How likely is it that the hazard will occur? This determination requires some judgment. If there have been “near-misses” or actual cases, then the likelihood of a recurrence would be considered high. If the pulley is exposed and easily accessible, that also is a consideration. In this example, the likelihood that the hazard will occur is high because there is no guard preventing contact, and the operation is performed while the machine is running. By following the steps in this example, you can organize your hazard analysis activities.