Track Percentages of Control Methods by Category - Safetip #190

Safety Tip and Best Practice
November 06, 2019

Our latest Safetip is about tracking the percentage of each category of measures in the hierarchy of controls.

The Hierarchy of Controls and the STOP Principle

Organizations must control exposures to workplace hazards in order to reduce risks of injury or illness and protect workers.

The hierarchy of controls can be used to determine the most effective and feasible measures:

Elimination and substitution are the most effective methods. But they can also be potentially costly and difficult to implement, especially in an existing process (as opposed to a process at the design stage). Big changes in equipment and procedures may be needed.

Engineering controls prevent contact between the hazard and the worker through changes to a plant, equipment or process. Well-designed engineering controls can provide a high level of protection. Engineering controls can also be costly, but they’re very effective.

Administrative controls change the way the work is performed or organized through modified schedules and work shifts, and work practices such as operating procedures, training, housekeeping, equipment maintenance, etc.

Personal Protective Equipment creates a physical barrier between the worker and the hazard to reduce exposure to chemicals, air contaminants, noise, etc. It can also consist of fall protection equipment (safety harnesses, body belts, lanyards).

Administrative controls and PPE are less costly and more feasible, but they’re also less effective than the other methods.

Another way to look at a hierarchy of measures, especially regarding exposure to dangerous chemicals, is through the STOP Principle:

  • Substitution of dangerous chemicals (or processes) with safer alternatives. This also covers the complete elimination of a chemical or process.
  • Technological measures that minimize the concentration of dangerous chemicals in the exposure zone, or enclose or encapsulate a process or operation.
  • Organizational measures that minimize the number of exposed workers and/or the duration and intensity of exposure.
  • Personal protective equipment, i.e. wearing protective clothing or equipment as a barrier to exposure.

A Suggested Leading Indicator

As a general rule, it’s better to implement control methods that are higher in the hierarchy as much as possible. It’s better to “engineer-out” a hazard.

This will not always be possible because of cost or feasibility, but it’s good to take the habit of aiming for the most effective and protective methods.

Implementing control methods that are high in the hierarchy is an indication of better safety performance.

In fact, a document from OSHA, “Using Leading Indicators to Improve Safety and Health Outcomes”, suggests the following leading indicator for measuring the implementation of recommended practices for hazard prevention and control:

“Percentage of recommendations implemented that pertain to PPE hazard controls, administrative controls, engineering controls, substitution, and elimination.”

When hazards are identified and controls are put in place, keep track of the percentage of each category of implemented control method.

If you notice that the methods at the bottom of the hierarchy (administrative controls, PPE) form a big portion, that may indicate that you need to improve your hazard prevention and control practices.

Our Safetips share safety tips or best practices that contribute to safety excellence. Visit Enablon Insights regularly for new Safetips!



Jean-Grégoire Manoukian

Content Thought Leader