Hierarchy of Control Measures for Infectious Diseases

To help determine what actions, processes and precautions to include in the control plan, workplace health and safety professionals may consider a system called the Hierarchy of Hazard Control or “Hierarchy of Controls.” It identifies options based upon effectiveness, from the most effective (elimination of the hazard) to the least effective (use of personal protective equipment - PPE). The health and safety professional’s goal is to identify the most effective yet practical means to control risk and to put these decisions and options into the control plan for implementation. 

Figure 1 shows the Hierarchy of Controls listed in decreasing order of preference.


Elimination and Substitution: Elimination and substitution (physically removing or replacing the hazard) are the most effective controls. They are also the most difficult to implement or simply may be impractical. 

Engineering Controls: Engineering controls seek to isolate people from the hazard or remove it before it comes in contact with the worker. Isolation is an example of an engineering control. Isolation is the separation of an infected person from others. It is frequently used for infectious aerosols or airborne diseases like tuberculosis. To prevent the spread of disease from the isolation area, engineering controls such as barriers to access and special ventilation may be used. 

Administrative Controls: These are changes in the way work is done. Some examples include changing procedures or implementing new ones, employee training, and installing signs and warning labels. Administrative controls do not remove hazards. Instead, they limit exposure or reduce exposure through behavior changes and hazard awareness. 

PPE: Personal protective equipment (PPE) includes gloves, protective clothing, hardhats, safety glasses, safety footwear, and respirators. PPE is frequently used where hazards are not particularly well controlled. Work practices, or administrative controls, and personal protective equipment are less desirable controls than engineering controls.