Prevent Heat Stress on the Job

It was recently reported in the news that based on global temperatures, July 2019 was the hottest month on record, with temperatures exceeding the previous record set in July 2016.  This means that for workers in industries such as construction, food and beverage and other jobs that require active work in hot or humid conditions, the risk of illness from heat exposure is not only high, it has also increased in recent years.  Daily temperatures, particularly during the July and August months, have continued to break records in last ten years compared to historically recorded temperatures.

To address these concerns, Heat Illness Prevention Plans are included in OSHA-approved State plans across the United States plans and companies must comply with these regulations.

Companies are required to do their part to protect workers from heat stress.  But how can this be achieved and what should you know? What procedures, processes or personal protective equipment (PPE) can you put in place to ensure that your workers are kept safe? Heat stress in the workplace must be managed by taking precautionary steps and limiting employee exposure to exceedingly high working temperatures.

In order to prevent heat stress from occurring, it is important to understand the body’s response to heat.  Where a person’s body is exposed to prolonged elevated temperatures, the body turns on its cooling mechanism in order to generate sweat and release heat externally.  Blood rushes to the skin surface and profuse sweating ensues, but if the body is unable to reduce its core temperature quickly enough, this core temperature begins to rise. Workers should not be placed in situations where there core body temperature is allowed to rise above 38⁰ Celsius, the temperature above which persons begin to exhibit signs of heat illness.

Heat stress can manifest in several different ways and it is important to recognize the symptoms.

All employers should understand the signs of each type of heat illness, and the appropriate level of first aid that should be provided. The table below, taken from the OSHA website on Heat-relates illness and First Aid, provides a snapshot of four types of heat illnesses and the first aid measures to be taken.

IllnessSymptomsFirst Aid
Heat stroke
  • Confusion or hallucination
  • Fainting
  • Seizures
  • Very high body temperature
  • Red, hot, dry skin (or excessive sweating in some cases)
  • Call 911

While waiting for help:

  • Place worker in shady, cool area
  • Loosen clothing, remove outer clothing
  • Fan air on worker; cold packs in armpits
  • Wet worker with cool water; apply ice packs, cool compresses, or ice if available
  • Provide fluids (preferably water) as soon as possible
  • Stay with worker until help arrives
Heat exhaustion
  • Heavy sweating
  • Clammy skin
  • Fast, shallow breathing
  • Extreme weakness
  • Pale Complexion
  • Headache
  • Nausea or vomiting
  • Dizziness
  • Light headedness
  • Muscle Cramps
  • Have worker sit or lie down in a cool, shady area
  • Give worker plenty of water or other cool beverages to drink
  • Cool worker with cold compresses/ice packs
  • Take to clinic or emergency room for medical evaluation or treatment if signs or symptoms worsen or do not improve within 60 minutes.
  • Do not return to work that day
Heat Syncope
  • Light-headedness, dizziness and fainting
  • Have worker sit or lie down in a cool, shady area
  • Give worker plenty of water or other cool beverages to drink
Heat cramps
  • Muscle spasms
  • Pain
  • Usually in abdomen, arms, or legs
  • Have worker rest in shady, cool area
  • Worker should drink water or other cool beverages
  • Wait a few hours before allowing worker to return to strenuous work
  • Have worker seek medical attention if cramps don’t go away
Heat rash
  • Clusters of red bumps on skin
  • Often appears on neck, upper chest, folds of skin
  • Try to work in a cooler, less humid environment when possible
  • Keep the affected area dry


Understanding the signs and symptoms are important, but prevention is key.

There are several methods that companies can employ to prevent worker heat stress.

  1. Provision of Cold Beverages:
    1. Ensure that cold water is available to employees working outdoors or inside hot and humid environments in amounts that are sufficient to prevent dehydration.
    2. Offering employees drinks such as Gatorade should also be considered as these drinks include electrolytes that are lost during sweating. Gatorade restores electrolytes such as potassium so that further dehydration can be prevented.
  2. Provision of Fruits: Companies can supply fresh fruits such as bananas and apples to help restore electrolytes along with replenishing the water intake as highlighted above.
  3. Allow for Acclimatization: New workers unaccustomed to working in hotter climates should be given up to two weeks to acclimatize to their new working environments prior to being given a full workload.
  4. Shaded or Air-conditioned Areas: Remind workers that if they begin to experience the first signs of heat stress, they should leave the work area immediately and move to a cool, shaded location. If possible, workers should relocate to an air conditioned building in order to prevent worsening signs of heat stress.
  5. Rest: Heat stress may cause persons to feel lightheaded and faint. Remind employees to take frequent breaks and rest with their legs slightly elevated if they experience dizziness.
  6. Clothing: Cool, breathable clothing should be provided to workers in hotter climates where heat stress is a concern.  In cases of imminent heat stress, clothing should be loosened in order to cool the body down more quickly.
  7. Provision of Cooling Systems: Where possible, provide adequate ventilation to employees working in warehouses or enclosed buildings, or where employees are working outdoors. This may be in the form of extractor fans (to release hot air externally), installing spot coolers in key operational areas, and providing heat barriers around furnaces.
  8. In Cases of Imminent Heat Stress, Use Cold Compress: Use cold water or cold ice compresses/ice packs. Place these on the affected person to speed up the cooling process if an employee begins to show signs of heat stress in addition to relocating them to a shaded area and sitting them down to rest.

Companies should also remind employees to:

  1. Reduce alcohol and caffeine intake as these drinks can cause further dehydration.
  2. Limit strenuous activities outdoors during the hottest hours between 11:00am to 3:00pm.
  3. Refrain from smoking, which can constrict blood vessels and can inhibit the body’s ability to acclimatize to heat.

New PPE technologies can also bring added comfort to workers in hot and humid environments.

Other options that companies can explore are new Personal Protective Equipment technologies such as cooling vests or Powered Air Purifying Respirators (PAPRs) where respirators are required.  PAPRs provide constant airflow and are perfect for employees working in humid, hot environments.  Cool air from PAPRs can also extend to the upper torso for increased comfort of workers.

Heat stress should not be taken lightly.  At the Safety Services Company, we encourage companies to engage in monitoring environmental conditions to provide a safe and comfortable working environment for all of their employees.

To see how we can solve your company’s heat stress prevention needs, check out our products and services here or call us at (866) 329-5407 today.

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