Heat stress in the workplace

In addition to temperature, increased relative humidity, decreased air movement, or lack of shading from direct heat (radiant temperature) can all affect the potential for heat stress in your workplace.

Relative humidity can dramatically affect the “feels like” temperature or heat index. We are particularly sensitive to humidity, and this is because our skin relies on air to get rid of moisture. Sweating is your body's cooling mechanism, but if the air is at 100% relative humidity, sweat will not evaporate into the air. As a result, we feel much hotter than the actual temperature. For example, if the temperature is 86F and the relative humidity is 90%, then the heat index is actually 105F, making heat-related illnesses more likely to occur.