Five Basic Hazard Control Strategies In The Hierarchy Of Controls

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After reviewing your list of hazards with the employee, next consider using hazard control methods that will eliminate or reduce them.

There are two primary strategies to permanently or temporarily reduce the risk of injury.

  1. Eliminate or mitigate the hazard.
  2. Eliminate or mitigate exposure to the hazard.

Each of these strategies employs a number of prioritized methods within what’s called the “Hierarchy of Controls”. The rest of this module will discuss the various hazard control methods within the hierarchy.

Hazard Control Strategies

Information obtained from a job hazard analysis is most useful when hazard control measures are developed and incorporated into the job.

A basic hazard control principle is that we must either (1) eliminate the hazard or (2) control exposure to the hazard. The second principle is that it’s more effective to eliminate the hazard than to control exposure to the hazard. These two important principles guide safety and health professionals in constructing a “hierarchy” of hazard control strategies.

ANSI/ASSP Z10-2012, Occupational Health and Safety Management Systems, encourages employers to use the following hierarchy of hazard controls:

  1. Elimination: Eliminate the hazard if you can. If you can do that, you eliminate exposure at the same time, and risk of an accident.
  2. Substitution: If you can replace a greater hazard with a lesser hazard, you mitigate the risk.
  3. Engineering controls: Design and redesign of equipment and machinery reduces exposure primarily through enclosure, isolation, barriers, and ventilation.
  4. Warnings: Create greater awareness of the hazards through the use of warning signs, placards, cones, alarms, etc.
  5. Administrative controls: Reduce exposure to the hazard through training, policies, procedures, practice, etc.
  6. Personal protective equipment: If we use PPE correctly, it can be effective in reducing exposure to hazards.

The idea behind this hierarchy is that the control methods at the top of the list are potentially more effective and protective than those at the bottom. Following the hierarchy normally leads to the implementation of inherently safer systems, ones where the risk of illness or injury has been substantially reduced.

Elimination and Substitution

Elimination and substitution, while most effective at reducing hazards, also tend to be the most difficult to implement in an existing process. These strategies are considered first because they have the potential of eliminating the hazard, thus greatly reducing the probability of an accident. Redesigning or replacing equipment or machinery may be expensive, but remember the average direct and indirect cost of a lost-work injury can be more than $50,000 and easily more than $1 million to close a fatality claim.

Engineering Controls

Engineering controls are built into the design of a facility, equipment or process to minimize the hazard. Engineering controls are a very reliable way to control worker exposures as long as the controls are properly designed, used and maintained.

If, during the JHA, you discover a hazard that can be engineered out, be sure to do it. One of the important goals of a JHA is to turn the dangerous step into a safe step that doesn’t require safety precautions. Engineering controls may include:

  • Enclosing the hazard using enclosed cabs, enclosures for noisy equipment, or other means;
  • Isolating the hazard with interlocks, machine guards, blast shields, welding curtains, or other means; and
  • Removing or redirecting the hazard such as with local exhaust ventilation.

Warnings and Administrative Controls

When elimination, substitution, and engineering control methods are insufficient to protect workers, warnings and administrative controls should be used. If we can’t get rid of the hazard in a JHA step, we’ll need to manage exposure to the hazard with safety precautions. Methods to eliminate or reduce employee exposure to hazards include:

  • placing warning signs, tape, cones, etc., to make workers aware of the hazard within a step
  • developing new policies, procedures, and practices to reduce frequency/duration of exposure
  • revising work schedules to reduce the frequency/duration of exposure
  • training

Personal Protective Equipment

Many procedures developed with a JHA will include the need to use PPE. Examples of PPE include respirators, hearing protection, protective clothing, safety glasses, and hardhats. PPE is acceptable as a control method in the following circumstances:

when engineering controls are not feasible or do not totally eliminate the hazard while engineering controls are being developed

when safe work practices do not provide sufficient additional protection during emergencies when engineering controls may not be feasible

Now let’s take a look at what our sample JHA looks like now that we’ve identified some hazards and their related preventive measures in each step.


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