What does duration refer to?

• A. The total project duration.
• B. The time between start and finish of a shift.
• C. The amount of time a person is continually exposed to a risk factor.
• D. The maximum safe exposure time.

Answer: (C)

In exposure assessment, duration means the length of time a person is exposed to a hazard. It’s about how long the exposure lasts, which directly affects the dose a person receives when combined with the hazard’s intensity.

The correct choice describes this as the amount of time a person is continually exposed to a risk factor, which is the core idea of duration. It isn’t about the overall project timeline, nor merely the clock of a shift, and it isn’t the regulatory limit of how long exposure is allowed (the maximum safe exposure time) but rather the actual exposure period itself.

For example, if someone works near a solvent for two hours, the duration of exposure is two hours, assuming the exposure is continuous. This duration, together with the solvent’s concentration, helps determine the total dose and potential health risk.