Which term indicates the average level of exposure over a full workday?

The correct term that indicates the average level of exposure over a full workday is the Time Weighted Average. This concept is fundamental in occupational health and safety as it reflects the cumulative exposure a worker experiences throughout their work shift. The Time Weighted Average takes into consideration the varying levels of exposure that may occur at different times during the day and adjusts the average accordingly, ensuring that it accurately represents the worker’s overall exposure to a hazardous substance.

In practice, the Time Weighted Average is useful for assessing compliance with occupational exposure limits, as it helps in determining whether a worker's exposure levels remain within safe thresholds. This is critical for ensuring worker health and safety by preventing chronic health issues that can arise from prolonged exposure to hazardous substances.

Other terms, such as Permissible Exposure Limit and Threshold Limit Value, refer to specific concentrations recommended or mandated for occupational exposures, providing set limits for safety but not accounting for the average over time like the Time Weighted Average does. The Short-Term Exposure Limit specifically addresses maximum exposure levels over a shorter period, typically 15 minutes, to prevent acute effects, further differentiating it from the daily average reflection that the Time Weighted Average provides.