How to Respond to Heat Illnesses

December 15, 2023

Here are some key points.

  • Acute heat stress can be life-threatening.
  • Act quickly but calmly to help a co-worker who shows signs of heat stress.
  • Know where our emergency numbers are posted, and have someone call for emergency medical help when you suspect heat stress.
  • Use the coolest possible PPE that’s appropriate for the job.

Heat stress can be very serious

  • Working outdoors in hot, humid weather can result in heat stress, a condition that occurs when our bodies build up more heat than they can handle.
  • Agricultural workers who work in the hot sun for long periods of time are especially susceptible to heat stress.
  • Acute heat stress can be life-threatening, and needs immediate medical attention.
  • You can help by knowing what steps to take if a co-worker shows signs of a heat-related illness.
Person sitting on bench suffering from heat exhaustion

There are a number of different types of heat illnesses, including heat rash, heat exhaustion, and heat stroke.

Person helping person who fainted from heat exhaustion

Use a sponge and cool water, if available, to cool the person off.

Person in protective coveralls and equipment reading label of pesticide container

Never take off your PPE when working with pesticides, even if you feel hot.

Recognizing heat illnesses

  • There are a number of different types of heat illnesses, including heat rash, heat exhaustion, and heat stroke.
  • Heat stroke, which often occurs suddenly, is the most life-threatening and requires immediate medical treatment.
  • Although some of the specific symptoms of heat illnesses may vary, here are some common warning signs:
  • exhaustion
  • headaches
  • nausea
  • muscle weakness
  • muscle or abdominal cramps
  • dizziness or fainting
  • chills
  • loss of coordination
  • confusion, including slurred speech
  • severe thirst and dry mouth
  • aggressive or irrational behavior
  • It’s important to stay calm but to act quickly if you think someone is showing signs of a heat illness.

How to respond

  1. Move the person into the shade or another cool area.
  2. Have someone call for immediate medical help.
  3. Remove outer clothing (jacket, hat, etc.) as well as any personal protective equipment (PPE). Be sure, however, not to use your bare hands to touch PPE or outer clothing that may be contaminated with pesticides. Put on gloves first.
  4. Cool the person off. If available, use cool water to sponge the person’s body and legs. Sponge or splash the water on the person’s face, neck, hands and forearms.
  5. If conscious and alert, have the person drink cool water or a sports drink.
  6. Try to keep the person still until medical help arrives.

Heat illnesses and pesticides

  • The symptoms of heat exhaustion and some pesticide poisonings are very similar, but their treatments are very different.
  • That’s why it’s important to seek immediate medical help if you are uncertain of the problem.
  • If you apply pesticides, it’s a good idea to use the minimum amount of PPE that’s required by the pesticide label when working in the hot sun.
  • Also, if you typically wear a plastic or other barrier-coated spray suit, ask your supervisor about the possibility of wearing a more “breathable” material.
  • Some chemical-resistant suits are made of these new materials, which allow heat and perspiration to escape. They are not vapor tight, however, and are not suitable for working with liquid forms of highly toxic pesticide concentrates.

Sun Safety Do’s and Don’ts


  • Become familiar with the symptoms of heat-related illnesses.
  • Quickly move the person into the shade when you suspect heat stress.
  • Remember to drink a lot of water before work, during breaks, and after work so you are less prone to heat stress.


  • Forget to seek immediate emergency medical help when you suspect heat stress.
  • Touch contaminated PPE with your bare hands.
  • Leave someone who may have a heat-related illness alone.

Download Printable PDF