People with a pre-existing condition, such as limited mobility, heart disease, and taking certain medications can be at higher risk to a heat stress injury. The most serious are heat stroke and heat exhaustion. With or without a pre-existing condition, heat stroke and exhaustion are both serious medical emergencies and action should be taken immediately.
OSHA considers extreme conditions working 6 to 8 hours directly in hot weather, a setting common for most individuals in agriculture. A heat stress injury occurs when the body cannot regulate its temperature. If the body is working correctly, it is self-cooled by perspiration. When the body's temperature rises faster than it can cool itself, the core temperature begins to rise quickly and heat stress injuries result.
These Injuries Include:
• The body's temperature rises to critical levels.
• Confusion, irrational behavior, loss of consciousness, convulsions, lack of sweating, hot dry skin, and abnormally high body temperature.
Treatment: Do not consume fluids when having a heat stroke and seek medical treatment immediately. Delaying medical treatment could result in death.
• Headache, nausea, weakness, thirst.
Treatment: Get out of the sun. Lie down and loosen clothing. Apply cool, wet cloths. Fan or go to air-conditioned room or vehicle, if possible. Take sips of water. If nausea occurs, discontinue water. If vomiting continues or if little to no improvement after 30 minutes, seek immediate medical attention.
• Caused by dehydration.
Prevention: Water consumption every 15 to 20 minutes. Carbohydrate-electrolyte replacement beverages help prevent a loss of sodium caused by excessive sweating.
Treatment: Firm pressure on cramping muscles or gentle massage will help relieve spasms. Take sips of water. If nausea occurs, discontinue water.
• Loss of consciousness caused by blood pools in the extremities of the brain caused by lack of oxygen to the brain.
Prevention: Gradually become acclimatized to the hot environment. People need to be reacclimatized to the heat after any "time off" or hospitalization.
Eight steps to safely working in extreme heat:
1. Slow down.
• When possible, strenuous work should be scheduled for the coolest time of day.
2. Dress lightly.
• Lightweight, light-colored clothing reflects heat and sunlight and helps your body maintain normal temperatures.
• Even in extreme heat, safety gear needs to be worn if using tools or removing heavy debris.
3. Avoid foods that are high in protein because they increase metabolism, increasing body heat and water loss.
4. Drink water.
• Water cools the body.
• People with epilepsy, heart, kidney, or liver disease, are on fluid-restricted diets, or have a problem with fluid retention should consult a physician if possible before increasing fluid consumption.
5. Do not drink alcoholic beverages.
6. Certain medications increase heat and ultraviolet sensitivity. Also consult with a doctor or pharmacist about current medications before working in extreme heat.
7. Spend time in air-conditioned places.
• Spending some time each day in an air-conditioned environment will give some protection. If working in the fields try sitting in the truck for a few minutes to cool off.
8. Do not get too much sun and use sunscreen.
• Sunburn makes reducing body temperature more difficult.
This fact sheet was reviewed by Karen Mancl, PhD, Professor, Food, Agricultural and Biological Engineering, The Ohio State University; Josh Svarda, Program Coordinator, Easter Seals Work Resource Center.
Occupational Safety & Health Administration. 2017. "Section III, Chapter IV: Heat Stress." In OSHA Technical Manual. Washington, D.C.: United States Department of Labor.
University of Florida Extension. 2020. Disaster Handbook. Gainesville, FL: University of Florida Institute of Food and Agricultural Sciences. PDF.
About AgrAbility Based Fact Sheets
These fact sheets were developed to promote success in agriculture for Ohio's farmers and farm families coping with a disability or long-term health condition. AgrAbility offers information and referral materials such as this fact sheet, along with on-site assessment, technical assistance, and awareness in preventing secondary injuries. Fact sheets were developed with funding from NIFA, project number OHON0006.