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704 Hazard Analysis and Control
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Controlling Hazards

Traditionally, a prioritized "Hierarchy of Controls" (HOC) has been used to implement feasible and effective exposure controls to protect workers.

The idea behind the Hierarchy of Controls (HOC) is that the strategies at the top of the list are generally more effective and protective than those at the bottom. Following the hierarchy typically leads to inherently safer systems—ones where the risk of illness or injury is significantly reduced.

The first three strategies protect employees by physically eliminating or reducing hazards.

  1. Elimination completely remove hazards
  2. Substitution reduce or replace hazards
  3. Engineering Controls modify or isolate hazards

The final three strategies protect employees by eliminating or reducing exposure to hazards.

  1. Warnings raise employee awareness of the hazard
  2. Administrative/Work Practice Controls mandate compliance with safe work behaviors
  3. Personal Protective Equipment (PPE) places barriers between hazards and employees

Interim Measures

Using a lower priority hazard control method over another higher priority control strategy may be appropriate for providing interim (temporary) protection until the hazard is abated permanently. If you can't eliminate the hazard entirely, the interim control measures will likely be a combination of control methods used together. OSHA believes that feasible interim measures are always available if higher-level control methods are not possible.

Knowledge Check Choose the best answer for the question.

5-1. Which strategy protects employees by isolating or modifying hazards?