OSHA’s campaign to keep workers safe in the heat

OSHA’s Heat Illness Prevention campaign, launched in 2011, educates employers and workers on the dangers of working in the heat. Through training sessions, outreach events, informational sessions, publications, social media messaging and media appearances, millions of workers and employers have learned how to protect workers from heat. OSHA’s safety message comes down to three key words: Water. Rest. Shade.

Dangers of working in the heat

Every year, dozens of workers die and thousands more become ill while working in extreme heat or humid conditions. More than 40 percent of heat-related worker deaths occur in the construction industry, but workers in every field are susceptible. There are a range of heat illnesses and they can affect anyone, regardless of age or physical condition.

Employer responsibility to protect workers

Under OSHA law, employers are responsible for providing workplaces free of known safety hazards. This includes protecting workers from extreme heat. An employer with workers exposed to high temperatures should establish a complete heat illness prevention program.

  • Provide workers with water, rest and shade.
  • Allow new or returning workers to gradually increase workloads and take more frequent breaks as they acclimatize, or build a tolerance for working in the heat.
  • Plan for emergencies and train workers on prevention.
  • Monitor workers for signs of illness.

Why is heat a hazard to workers?

When a person works in a hot environment, the body must get rid of excess heat to maintain a stable internal temperature. It does this mainly through circulating blood to the skin and through sweating.
When the air temperature is close to or warmer than normal body temperature, cooling of the body becomes more difficult. Blood circulated to the skin cannot lose its heat. Sweating then becomes the main way the body cools off. But sweating is effective only if the humidity level is low enough to allow evaporation, and if the fluids and salts that are lost are adequately replaced.
If the body cannot get rid of excess heat, it will store it. When this happens, the body’s core temperature rises and the heart rate increases. As the body continues to store heat, the person begins to lose concentration and has difficulty focusing on a task, may become irritable or sick, and often loses the desire to drink. The next stage is most often fainting and even death if the person is not cooled down.
Excessive exposure to heat can cause a range of heat-related illnesses, from heat rash and heat cramps to heat exhaustion and heat stroke. Heat stroke can result in death and requires immediate medical attention.
Exposure to heat can also increase the risk of injuries because of sweaty palms, fogged-up safety glasses, dizziness and burns from hot surfaces or steam.

Who could be affected by heat?

Workers exposed to hot indoor environments or hot and humid conditions outdoors are at risk of heat-related illness, especially those doing heavy work tasks or using bulky or non-breathable protective clothing and equipment. Some workers might be at greater risk than others if they have not built up a tolerance to hot conditions, or if they have certain health conditions. The table below shows some environmental and job-specific factors that increase the risk of heat-related illness.

Factors that put workers at greater risk
Environmental
  • High temperature and humidity
  • Radiant heat sources
  • Contact with hot objects
  • Direct sun exposure (with no shade)
  • Limited air movement (no breeze, wind or ventilation)
Job-Specific
  • Physical exertion
  • Use of bulky or non-breathable protective clothing and equipment

Workers who are suddenly exposed to working in a hot environment face additional, but generally avoidable hazards to their safety and health. New workers and those returning from time away are especially vulnerable. That’s why it is important to prepare for the heat: educate workers about the dangers of heat, and acclimatize workers by gradually increasing the workload or providing more frequent breaks to help new workers and those returning to a job after time away build up a tolerance for hot conditions.

How do I know if it’s too hot?

  • The temperature rises
  • Humidity increases
  • The sun gets stronger
  • There is no air movement
  • No controls are in place to reduce the impacts of equipment that radiates heat
  • Protective clothing or gear is worn
  • Work is strenuous

The heat index, which takes both temperature and humidity into account, is a useful tool for outdoor workers and employers (see Using the Heat Index: A Guide for Employers).

How can heat-related illness be prevented?

Heat-related illnesses can be prevented. Important ways to reduce heat exposure and the risk of heat-related illness include engineering controls, such as air conditioning and ventilation, that make the work environment cooler, and work practices such as work/rest cycles, drinking water often, and providing an opportunity for workers to build up a level of tolerance to working in the heat. Employers should include these prevention steps in worksite training and plans. Also, it’s important to know and look out for the symptoms of heat-related illness in yourself and others during hot weather. Plan for an emergency and know what to do — acting quickly can save lives!

> Go to Prevention

Heat-related Illnesses and First Aid

Illustration of a man's head who seems to have a high body temperature

Heat stroke, the most serious form of heat-related illness, happens when the body becomes unable to regulate its core temperature. Sweating stops and the body can no longer rid itself of excess heat. Signs include confusion, loss of consciousness, and seizures. Heat stroke is a medical emergency that may result in death! Call 911 immediately.
Illustration of a man's head who sweating
Heat exhaustion is the body’s response to the loss of water and salt from heavy sweating. Signs include headache, nausea, dizziness, weakness, irritability, thirst and heavy sweating.
Illustration of a leg which denotes cramping
Heat cramps are caused by the loss of body salts and fluid during sweating. Low salt levels in muscles cause painful cramps. Tired muscles—those used for performing the work—are usually the ones most affected by cramps. Cramps may occur during or after working hours.
Heat rash, also known as prickly heat, is skin irritation caused by sweat that does not evaporate from the skin. Heat rash is the most common problem in hot work environments.

For more information about heat-related illnesses:

The Campaign

OSHA’s Heat Illness Prevention campaign, launched in 2011, educates employers and workers on the dangers of working in the heat. Through training sessions, outreach events, informational sessions, publications, social media messaging and media appearances, millions of workers and employers have learned how to protect workers from heat. OSHA’s safety message comes down to three key words: Water. Rest. Shade.

Dangers of Working in the Heat

Every year, dozens of workers die and thousands more become ill while working in extreme heat or humid conditions. More than 40 percent of heat-related worker deaths occur in the construction industry, but workers in every field are susceptible. There are a range of heat illnesses and they can affect anyone, regardless of age or physical condition.

Heat-related Illnesses and First Aid

Heat stroke, the most serious form of heat-related illness, happens when the body becomes unable to regulate its core temperature. Sweating stops and the body can no longer rid itself of excess heat.
Symptoms: Signs include confusion, loss of consciousness and seizures.
First Aid: Heat stroke is a medical emergency that may result in death! Call 911 immediately. While waiting for help place the worker in a shady and cool area; loosen clothing and remove outer clothing; fan air on the worker and place cold packs in armpits; wet the worker with cool water; provide fluids (preferably water) as soon as possible and stay with the worker until help arrives.
Heat exhaustion is the body’s response to loss of water and salt from heavy sweating.
Symptoms: Signs include headache, nausea or vomiting, dizziness, weakness, light headedness, irritability, thirst and heavy sweating.
First aid for heat exhaustion includes: have the worker sit or lie down in a cool, shady area; give the worker plenty of water or other cool beverages to drink; cool the worker with cold compresses or ice packs; if symptoms worsen or do not improve within 60 minutes, take the worker to a clinic or emergency room for evaluation; the worker should not return to work that day.
Heat cramps are caused by the loss of body salts and fluid during sweating. Low salt levels in muscles cause painful cramps. Tired muscles—those used for performing the work—are usually the ones most affected by cramps. Cramps may occur during or after working hours.
Symptoms include muscle spasms, pain usually in the abdomen, arms or legs
First aid for heat cramps include: have worker rest in a shady, cool area; worker should drink water or other cool beverages; wait a few hours before allowing the worker to return to strenuous work; have worker seek medical attention if cramps don’t go away.
Heat rash, also known as prickly heat, is skin irritation caused by sweat that does not evaporate from the skin. Heat rash is the most common problem in hot work environments.
Symptoms include clusters of red bumps on the skin, often appearing on the neck, upper chest and in folds of skin.
First aid includes keeping the worker in a cooler, less humid environment when possible and keeping the affected area dry.

Employer Responsibility to Protect Workers

Under OSHA law, employers are responsible for providing workplaces free of known safety hazards. This includes protecting workers from extreme heat. An employer with workers exposed to high temperatures should establish a complete heat illness prevention program.

  • Provide workers with water, rest and shade.
  • Allow new or returning workers to gradually increase workloads and take more frequent breaks as they acclimatize, or build a tolerance for working in the heat.
  • Plan for emergencies and train workers on prevention.
  • Monitor workers for signs of illness.

Resources

OSHA’s Occupational Exposure to Heat page explains what employers can do to keep workers safe and what workers need to know – including factors for heat illness, adapting to working in indoor and outdoor heat, protecting workers, recognizing symptoms and first aid training. Also look for heat illness educational and training materials on OSHA’s Publications page.

HEAT ILLNESS CAN BE DEADLY

OSHA_heat_ad-colorThe 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 you don’t drink enough water and rest in the shade. You can suffer from heat exhaustion or heat stroke.
In 2014 alone, 2,630 workers suffered from heat illness and 18 died from heat stroke and related causes on the job. Heat illnesses and deaths are preventable.
 
 

Employers must protect workers from excessive heat

Under OSHA law, employers are responsible for providing workplaces free of known safety hazards. This includes protecting workers from extreme heat. An employer with workers exposed to high temperatures should establish a complete heat illness prevention program.

  • Provide workers with water, rest and shade.
  • Allow new or returning workers to gradually increase workloads and take more frequent breaks as they acclimatize, or build a tolerance for working in the heat.
  • Plan for emergencies and train workers on prevention.
  • Monitor workers for signs of illness.

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.

Working in full sunlight can increase heat index values by 15 degrees Fahrenheit. Keep this in mind and plan additional precautions for working in these conditions.

Who is affected?OSHA_heat_maintips

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. All workers are at risk 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.

What to do if a worker becomes ill?

  • Call a supervisor for help. If a supervisor is not available, call 911.
  • Have someone stay with the worker until help arrives.

Click here to listen to OSHA’s Heat Advisory Call.
Click here to download OSHA’s Heat Safety Tool Smartphone App.
Click here for more information from OSHA on heat safety.


OSHA is a Weather-Ready Nation Ambassador (WRN) committed to working with NOAA and other Ambassadors to strengthen national preparedness for and resilience against extreme weather.
How can OSHA help? Workers have a right to a safe workplace. If you think your job is unsafe or have questions, visit OSHA’s Worker’s Page or call 1-800-321-6742 (OSHA). It’s confidential. For other valuable worker protection information, such as Workers’ Rights, Employer Responsibilities, and other services OSHA offers, visit OSHA’s Workers’ page.
OSHA also provides help to employers. OSHA’s On-site Consultation Program offers free and confidential advice to small and medium-sized businesses in all states across the country, with priority given to high-hazard worksites. For more information or for additional compliance assistance contact OSHA at 1-800-321-6742 (OSHA).

HEAT ILLNESS CAN BE DEADLY.

osha sunEvery 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.

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. Working in full sunlight can increase heat index values by 15 degrees Fahrenheit. Keep this in mind and plan additional precautions for working in these conditions.

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.