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Hazard Versus Risk

The terms “hazard” and “risk” are frequently used interchangeably, but there is a distinct difference.


A hazard is any source of potential damage or harm to an individual’s health or life under certain conditions, whether at work or in the home.

Examples of hazards and their effects include:

  • Item
    Example: A cut from broken glass
  • Substance
    Example: Blistering from sodium hydroxide
  • Source of energy
    Example: A burn from a Bunsen burner
  • Condition
    Example: Slipping and falling on a wet floor


Risk is the chance or probability of a person being harmed or experiencing an adverse health effect if exposed to a hazard.

  • Example: A wet floor is a hazard, and there is a probability (risk) that someone might be harmed by slipping and falling.

Risks can be reduced by taking measures to minimize or control the hazard.

  • Example: The risk of falling could be reduced by placing signs warning of the wet floor or blocking access to the area where the hazard exists.

Risk Assessment

Risk assessment is the process of estimating the probability of harm from a hazard (the severity of the hazard multiplied by the probability of exposure to the hazard) by considering the process or the laboratory procedure that will be used with the hazard.

Conducting a risk assessment involves estimating the risk and then identifying steps to minimize the risk—reducing the quantity of the hazard being handled, using chemical hoods and protective barriers, devising safe procedures for handling the hazard, and using personal protective equipment (PPE).

All chemistry and science teachers who work with students in the laboratory should know how to undertake and document a risk assessment.

Learn more about risk assessment! >>

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