Preventing Heat Illness

Prevent Heat Illness in Outdoor Workers

HEAT ILLNESS CAN BE DEADLY. Every year, thousands of workers become sick from exposure to heat, and some even die. Heat illnesses and deaths are preventable. Employers are responsible for providing workplaces that are safe from excessive heat.

What is heat illness?

The body normally cools itself by sweating. During hot weather, especially with high humidity, sweating isn’t enough. Body temperature can rise to dangerous levels if precautions are not taken such as drinking water frequently and resting in the shade or air conditioning. Heat illnesses range from heat rash and heat cramps to heat exhaustion and heat stroke. Heat stroke requires immediate medical attention and can result in death.

How can heat illness be prevented?

Employers should establish a complete heat illness prevention program to prevent heat illness. This includes: provide workers with water, rest and shade; gradually increase workloads and allow more frequent breaks for new workers or workers who have been away for a week or more to build a tolerance for working in the heat(acclimatization); modify work schedules as necessary; plan for emergencies and train workers about the symptoms of heat-related illnesses and their prevention; and monitor workers for signs of illness. Workers new to the heat or those that have been away from work and are returning can be most vulnerable to heat stress and they must be acclimatized (see box).

To prevent heat related illness and fatalities:

  • Drink water every 15 minutes, even if you are not thirsty.
  • Rest in the shade to cool down.
  • Wear a hat and light-colored clothing.
  • Learn the signs of heat illness and what to do in an emergency.
  • Keep an eye on fellow workers.
  • “Easy does it” on your first days of work in the heat. You need to get used to it.

If workers are new to working in the heat or returning from more than a week off, and for all workers on the first day of a sudden heat wave, implement a work schedule to allow them to get used to the heat gradually.

Remember these three simple words: Water, Rest, Shade. Taking these precautions can mean the difference between life and death.

Who is affected?

Any worker exposed to hot and humid conditions is at risk of heat illness, especially those doing heavy work tasks or using bulky protective clothing and equipment. Some workers might be at greater risk than others if they have not built up a tolerance to hot conditions, including new workers, temporary workers, or those returning to work after a week or more off. This also includes everyone during a heat wave.

Industries most affected by heat-related illness are: construction; trade, transportation and utilities; agriculture; building, grounds maintenance; landscaping services; and support activities for oil and gas operations.

About the Campaign

OSHA’s nationwide Heat Illness Prevention Campaign aims to raise awareness and teach workers and employers about the dangers of working in hot weather and provide valuable resources to address these concerns. Begun in 2011, the Heat Illness Prevention Campaign has reached more than 10.7 million people and distributed close to half a million fact sheets, posters, quick cards, training guides and wallet cards. OSHA is again joining with other federal and state agencies and non-governmental organizations to spread the word about preventing heat illness. For example, OSHA is continuing its partnership with the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service to include worker safety precautions in their Excessive Heat Watch, Warning, and Advisory Products.

Available on this web page are numerous resources that can be used to prevent heat illnesses:

  • The Educational Resources section links to information about heat illnesses and how to prevent them. Many of these resources target vulnerable workers with limited English proficiency and/or low literacy.
  • The Using the Heat Index section provides guidance to employers to develop a heat illness prevention plan.
  • The Training section includes a guide/lesson plan for employers and others to use in instructing workers on heat illness. There are links to additional resources in other languages.
  • The Online Toolkit section includes news releases, public service announcements (PSAs), drop-in articles about heat illness prevention that you can customize to share and campaign artwork.
  • The Fatality Map shows locations of outdoor worker, heat-related fatalities between 2008 and 2012. It is not an exhaustive list of all worker fatalities from heat exposure. The map provides a geographic reminder that Water.Rest.Shade. are vital to providing a safe and healthful environment when working outdoors in the heat.

The Heat Illness web page and many resources are available en español.