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Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the guidance for fully vaccinated people. CDC recommends universal indoor masking for all teachers, staff, students, and visitors to K-12 schools, regardless of vaccination status. Children should return to full-time in-person learning in the fall with layered prevention strategies in place.
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What Workers Need to Know about Heat Stress Prevention during the COVID-19 Pandemic

What Workers Need to Know about Heat Stress Prevention during the COVID-19 Pandemic

Your employer may tailor the existing heat illness prevention program and policies to the unique challenges of working during the COVID-19 pandemic.

More info about Heat Stress

Heat stress is the total amount of heat your body encounters. It may come from a variety of sources, such as:

  • Heat from work processes and machinery (e.g., forge)
  • Environmental temperatures, humidity, and lack of air movement (e.g., no wind or inadequate air circulation)
  • Internal metabolic processes (e.g., illnesses that create a fever)
  • Heat generated by your muscles from physical exertion

Clothing and personal protective equipment (PPE) may also trap heat, further increasing heat exposure.

Workers who are exposed to extreme heat, work in hot environments, or perform physically demanding work in moderate heat environments may be at risk for heat-related illnesses and injuries. The most severe form of heat-related illness is heat stroke, a life-threatening medical emergency that can result in death.

Early signs of heat stroke may include:

  • Confusion
  • Difficulty performing routine tasks or answering simple questions (e.g., “What is today’s date?” “Where are we?”)
  • Slurred speech

Late signs of heat stroke may include:

  • Seizures
  • Loss of consciousness
  • Organ failure resulting in death

In addition to training you on the signs and symptoms of heat-related illnesses, including heat stroke, your employer should provide instruction on general first aid and how to obtain prompt medical treatment for anyone who may experience a heat-related illness at work.

This CDC Guidance for Businesses and Employers highlights some of the changes you may see at your worksite to minimize the spread of the virus that causes COVID-19. Some of these may be part of your employer’s existing heat illness prevention program and may increase your risk for heat-related illnesses due to:

  • Loss of your body’s natural ability to adapt to heat (acclimatization). This can occur if your workplace has closed temporarily or if you have been off work for a week or more.
  • Lack of a re-acclimatization component of work re-entry plan if you have been out of the work environment for more than 1 week.
  • Increased heat burden associated with cloth face coverings or masks or, for healthcare workers, additional PPE required for COVID-19 (for example disposable plastic gowns and gloves). These can:
    • Trap heat close to the skin and prevent normal cooling like sweat evaporation.
    • Increase the effort required to breathe through a cloth face covering or mask, or, for healthcare workers, a respirator.
    • Increase anxiety you may feel during wear.
  • Increased physical activity if you need to do more than your usual job tasks due to social distancing requirements. For example, you might have to walk more or lift objects more frequently if there are fewer employees at your workplace.
  • Longer work shifts, resulting in spending more time in the hot work environment to catch up on work missed during earlier shutdowns.

How can you reduce your risk for heat-related illness during the COVID-19 Pandemic?

  • Talk with your healthcare provider (either your personal healthcare provider or your employer’s occupational health provider, if there is one) about your physical ability to work safely in a potentially hot environment. Be sure to discuss any pre-existing medical conditions you have, PPE (e.g., healthcare personnel) or cloth face covering or mask use, and social distancing practices.
  • Take time to get used to (re-acclimatize) heat stress.
    • When you work in hot environments, over time there are changes in body function that improves its ability to shed excess heat safely. These changes take time to happen and can be lost when away from the hot work environment for a prolonged period.
    • If you have been away from work for more than 1 week, your employer should place you on a re-entry work schedule that will allow you to be slowly re-introduced to working in a hot environment.
    • Returning workers can regain their ability to work in hot conditions in 2 to 3 days upon return to a job. Workers new to the job may take up to 14 days to fully acclimatize.
  • Identify a shift buddy to check for symptoms of heat-related illness.
    • Continue to follow your workplace social distancing requirements.
    • Wearing cloth face coverings or masks, or respirators (healthcare personnel) may make seeing facial expressions difficult. You will need to rely more on verbal check-ins with your buddy.
      • Verbal check-ins may include asking each other easy questions and listening for a correct reply given without hesitation or slurring.
      • If your buddy indicates they feel unwell or their reply is difficult to understand, alert your supervisor and begin first aid procedures.
  • Take longer and more frequent rest breaks.
    • Your employer may alter your work/rest schedule to account for additional heat stress by decreasing the amount and duration of the work part of the cycle and increasing the number and frequency of rest breaks.
    • Your employer may also modify work schedules so that the majority of work hours or most physically demanding tasks occur overnight or during cooler parts of the day, if this can be practically done.
  • Adjust target expectations for completed work.
    • Your employer should reassess daily expectations or goals if social distancing requirements add distance and time to your work tasks, decreasing the number of tasks you can safely complete each shift.
  • Wear cloth face coverings or masks that are lightweight and light in color.
    • Do not layer cloth face coverings or masks over respiratory protection, when respirators are needed (e.g. healthcare personnel).
    • Do not use cloth face coverings or masks with exhaust valves for source control.
    • Consider carrying a spare cloth face covering or mask. If your cloth face covering or mask gets wet, visibly soiled, or contaminated at work, take it off and store it to be laundered later, if possible.
  • Rehydrate and cool down safely.
    • Maintain social distancing (at least 6 feet) during rest breaks. Proper social distancing is very important during breaks as workers will need to remove cloth face coverings, masks, or respirators (for healthcare personnel) that cover the mouth in order to rehydrate.
      • Check your cloth face covering or mask during this time. If it feels or looks damp or dirty, take your cloth face covering or mask off carefully and replace it with a clean one before ending your break.
      • Avoid gathering around water refill stations or where drinks are stored.
    • If your employer provides water refill stations:
      • Consider using a refillable drinking bottle that can be stored inside a cooling station. This will ensure that you will not need to line up at the refill station. Label the bottle with your name.
      • If you need to refill your bottle again, be sure to maintain social distancing while in line.
      • Touch only the disposable paper cone or cup that you plan to use.
      • Avoid touching your drinking cup or bottle to the water dispenser when refilling it.
    • Be aware of the position of cooling and/or misting fans.
      • Avoid standing or sitting directly downwind of someone who is in front of a cooling fan. This will keep air from the fan from blowing respiratory droplets from them onto you.
    • Continue to monitor your buddy during rest breaks for signs and symptoms of heat-related illness, while maintaining social distancing.
  • Follow an emergency first aid plan for heat-related illnesses.
    • Immediately remove your coworker (or yourself) from the hot environment into a cool or shaded area.
    • Notify management or the nearest worker who can get help.
    • Remove PPE that is normally required for any job tasks, cloth face coverings or masks, and excess clothing from the affected worker to facilitate cooling.
    • If the affected worker is alert, provide them with cool liquids to drink.
    • If you suspect heat stroke:
      • Call 911.
      • Carefully remove all PPE that is normally required for any job tasks, cloth face coverings or masks, and excess clothing from the affected person to cool their body quickly in or with water or other cool liquids and resuscitation measures.
      • Cool the affected worker aggressively while waiting for the ambulance. You can use ice, cool water baths, or misting sprays. But if the worker is not fully conscious, take care to keep water from going into the worker’s mouth and lungs.
      • If providing first aid or resuscitation, continue wearing your PPE (e.g., healthcare personnel) or cloth face covering or mask.
More Information

For additional information or if you have any questions, contact CDC at:
CDCINFO: 1-800-CDC-INFO (1-800-232-4636) | TTY: 1-888-232-6348 | website: