Extreme heat affects workers’ health by creating conditions in which illnesses can arise, but new research shows high temperatures have significant impact on injuries as well. Estimates from a new study indicate about 80% of increased workers’ comp claims from high temperatures are for injuries not illnesses.

Higher temperatures are associated with a broad range of injuries, according to the W.E. Upjohn Institute for Employment Research.

Previous research has shown people can adapt to warmer climates, but the results from the new study reveal workers with outdoor jobs face additional challenges in adapting to high temperatures. This new research undercuts the optimism that people may eventually be able to adapt to extreme heat.

Where Effects Are Worst

Further, the study finds hot days are more harmful for outdoor workers in warmer climates than in cooler ones.

People working outdoors can’t take advantage of air conditioning the same way indoor workers can, and current technology doesn’t provide outdoor workers with enough protection. Avoiding heat hazards is easier when higher temperatures are rare. For example, outdoor workers in northern states can adjust their schedules to avoid the most physically demanding work when temperatures are highest.