If you thought fall’s cooler temperatures would eliminate the risk for heat exposure, think again. Keep reading to learn about the experience of an employer recently cited under OSHA’s bedrock employee protection standard.

A Pennsylvania plastic products maker was recently cited for violating OSHA’s General Duty Clause (GDC), Section 5(a)(1) of the OSH Act, for exposing employees to heat stress conditions. The GDC requires that covered employers provide “employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees.” In this case, OSHA found that during their 12-hour work shift, machine operators were exposed to excessive heat while operating rotational molding ovens operating at 600 degrees Fahrenheit.

OSHA Area Director Theresa A. Naim commented, “Heat stress is not only an outdoor health hazard. Employees working indoors in elevated temperatures can also demonstrate the symptoms of heat-related illness.” She added that heat stress can be reduced significantly when employers establish an effective heat illness prevention program.

On-the-job heat exposure is a risk during operations involving high air temperatures, radiant heat sources, high humidity, direct physical contact with hot objects, or strenuous physical activities. Affected workplaces may include foundries, brick-firing and ceramic plants, glass products facilities, rubber products plants, electric utilities, commercial kitchens, laundries, chemical plants, and smelters.

OSHA emphasizes that while thousands of workers become sick each year from occupational heat exposure, the illnesses and deaths that can result are preventable.

When working in a hot environment, the body must get rid of excess heat to maintain a stable internal temperature. This is done mainly through sweating and through circulating blood to the skin. Cooling becomes more difficult when the air temperature is close to or warmer than normal body temperature. Blood circulated to the skin cannot lose its heat, and sweating becomes the main way the body cools off. But sweating only works if the humidity level is low enough to allow evaporation.

Heat that cannot be eliminated is stored, which causes the body’s core temperature to rise and the heart rate to increase. This can lead to heat illness, with effects ranging from heat rash and cramps to heat exhaustion, heatstroke, or death. Symptoms of heat exhaustion include headache, dizziness, or fainting; weakness and wet skin; irritability or confusion; and thirst, nausea, or vomiting. Symptoms of heatstroke, a potentially fatal condition that requires immediate medical attention, include confusion or inability to think clearly, passing out or having seizures, and failure to sweat.

Workers toiling in indoor environments are at risk, especially those doing heavy work tasks or using bulky or nonbreathable protective clothing and equipment. Some may be at higher risk if they have not built up a tolerance to hot conditions or if they have certain health conditions.

Implement these measures to prevent heat-related illness:

• Engineering controls like air-conditioning and ventilation that make the work environment cooler;
• Work practices such as work/rest cycles, making sure workers drink water often, and providing an opportunity to build up a tolerance to working in the heat; and
• Employee and supervisor training that covers the symptoms of heat-related illness and makes sure they know what to do in case of an emergency.