FACTS

1. Millions of U.S. workers are exposed to heat in their workplaces. Although illness from exposure to heat is preventable, every year, thousands become sick from occupational heat exposure, and some cases are fatal. 
2. Most outdoor fatalities, 50% to 70%, occur in the first few days of working in warm or hot environments because the body needs to build a tolerance to the heat gradually over time. The process of building tolerance is called heat acclimatization. Lack of acclimatization represents a major risk factor for fatal outcomes.
3. Occupational risk factors for heat illness include heavy physical activity, warm or hot environmental conditions, lack of acclimatization, and wearing clothing that holds in body heat. 
4. Hazardous heat exposure can occur indoors or outdoors and can occur during any season if the conditions are right, not only during heat waves.
5. Working in a hot environment can trigger ailments that include heat rash, heat cramps, heat exhaustion and heatstroke – considered a medical emergency. Symptoms of heat exhaustion include feeling faint or dizzy; excessive sweating; cool, pale, clammy skin; nausea or vomiting; rapid, weak pulse; and muscle cramps.

STATS

• Some statistical approaches estimate that more than 1,300 deaths per year in the United States are due to extreme heat.
• According to the Bureau of Labor Statistics, 783 workers in the US died and more than 69,000 workers suffered serious injuries due to heat exposure on the job.
• Exposure to environmental heat led to 37 work-related deaths and 2,830 nonfatal occupational injuries and illnesses.
• Nearly 90 % (33) of the deaths occurred from June through September.
• Workers in transportation and material moving occupations were involved in 720 of the nonfatal injury and illness cases involving days away from work. 
• Heat-related illnesses accounted for 783 worker deaths and nearly 70,000 serious injuries in the United States from 1992 to 2016. And in 2018 alone, 3,950 workers experienced days away from work as a result of nonfatal injuries and illnesses from on-the-job heat exposure.
• According to projections conducted by the not-for-profit organization Climate Central, the number of dangerous heat days for 133 US cities, will increase from 20 a year on average in 2000 to 58 in 2050. A dangerous heat day is defined as one in which the heat index, accounting for heat and humidity, exceeds 104F (40C).