Preventing Heat Stress Illness

Kent McGuire – OSU Ag Safety & Health Coordinator

Although summer has started out with mild temperatures, we are approaching the time of year when hotter work environments can create potential health hazards. Working long hours in higher temperatures or non – shaded areas increase the risk of a heat stress illness such as heat exhaustion or heat stroke. These types of illnesses can occur when the body’s temperature rises faster than it can cool itself. At this point, the body cannot regulate its temperature and can very quickly become a serious medical emergency if precautions are not taken.

Planning ahead is essential to preventing heat related hazards. A primary indicator that can be used when planning to work during hot weather is the heat index. The heat index is a single value that takes both temperature and humidity into account to determine what it feels like to the human body. OSHA has developed a chart to help employers prepare and implement plans to protect employees when working in hot environments.

Some precautions and measures to use when preparing for hot weather work include:

- When possible, strenuous work should be scheduled for the coolest time of day (early morning or evening).

- Dress lightly.  Light-weight, light-colored clothing reflects heat and sunlight, and helps your body maintain normal temperatures.

- Take multiple short breaks in a shaded area or controlled environment, throughout the day.

- Use extreme caution when working around equipment or machines that will give off additional heat during operations.

- Provide ventilation to enclosed work locations with limited airflow, such as haymows.

-  Stay hydrated. Drink plenty of fluids before, during, and after strenuous activities. Cold fluids can also help cool the body. Plan ahead! Hydrating the body should start 24 hours before strenuous activity in higher temperatures.

- Do not work alone. Use the buddy system when working in isolated areas to monitor each other for signs and symptoms of heat stress.

- Avoid foods that are high in protein. These foods increase metabolism, increasing body heat and water loss.

- Avoid getting too much sun and use sunscreen. Sunburn makes reducing body temperature more difficult.

- Spend time in air-conditioned places, especially during periods of rest, which allow the body to recuperate.

- Provide training to employees about the hazards leading to heat stress and how to prevent them.


If heat stress is suspected:

- Get out of the sun.

- Lie down and loosen clothing.

- Apply cool, wet cloths. Fan or go to an air-conditioned room or vehicle, if possible.

- Take sips of cool water. If nausea occurs, discontinue water.

- Seek immediate medical attention if there is any question to severity of the heat stress illness.

More information about controlling heat stress illness can be found through The National Institute for Occupational Safety and Health (NIOSH)

For more information about agricultural safety, visit, or contact Kent McGuire, Safety & Health Coordinator for the OSU College of Food, Agricultural, and Environmental Sciences, at or 614-292-0588.