Using the Heat Index: An OSHA Guide for Employers


Share on facebook
Share on google
Share on twitter
Share on linkedin

Outdoor workers who are exposed to hot and humid conditions are at risk of heat-related illness, says OSHA. The agency recently published guidelines for workers while reminding employers the situation is particularly serious when hot weather arrives suddenly early in the season, before workers have had a chance to adapt to warm weather.

The OSHA release said the “heat index” is a single value that takes both temperature and humidity into account. The higher the heat index, the hotter the weather feels, since sweat does not readily evaporate and cool the skin. The heat index is a better measure than air temperature alone for estimating the risk to workers from environmental heat sources.

While OSHA said it does not have a specific standard that covers working in hot environments, employers have a duty to protect workers from recognized serious hazards in the workplace, including heat-related hazards. Workers performing strenuous activity, workers using heavy or non-breathable protective clothing, and workers who are new to an outdoor job need additional precautions beyond those warranted by heat index alone.

OSHA said workers new to outdoor jobs are generally most at risk for heat-related illnesses. For example, Cal/OSHA investigated 25 incidents of heat-related illness in 2005. In almost half of the cases, the worker involved was on their first day of work and in 80 percent of the cases the worker involved had only been on the job for four or fewer days. The agency recommends gradually increasing the workload for new employees and allowing more frequent breaks to help build up a tolerance for hot conditions.

June 4, 2019

Reader Interactions

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.