Skip links
Complete OSHA 10-hour in 2 days, Earn DOL Card (Live Webinar) with Click Here!

Heat Stress and Its Safety Measures

Many people, particularly those who do demanding labor in hot and humid working conditions, suffer from heat stress, particularly in the summer. Workers’ health and productivity are both adversely affected by excessive heat. Rashes, cramps, tiredness, and, in the worst-case scenario, heatstroke are all symptoms of heat stress. While heat rashes and heat cramps are unpleasant, heat exhaustion is far more dangerous and requires urgent medical attention.

It is esimated that there were 148 fatalities and 205 injuries due to heat-related factors in 2022. Heat stress has plenty of warning indicators. By observing these warning signs, workers can better regain control of the situation. Dizziness, lightheadedness, headache, nausea, vomiting, and diarrhea are some of the warning symptoms. Redirecting blood from internal organs and muscles to the skin results in these symptoms. Dehydration results from sweating.

Most workers in Construction Industry encounter heat stress regularly since they primarily work outdoors and are susceptible to the consequences of heat stress. Therefore, to safeguard their health, OSHA 30 Construction educates the preventative measures to protect themselves in such cases and other site hazards.

How does heat stress start?

As the air and skin temperatures normalize, radiation stops working. Convection is no longer possible since the circulating air is now warm rather than cool. Conduction is not possible if there is nothing cool to contact. In addition, if the air is humid, sweat will not evaporate. Heat stress is likely at temperatures between 85 and 95 degrees Fahrenheit, with humidity levels ranging from 30 to 60%. Workers are in even more danger when the temperature goes beyond 95 degrees F and the humidity rises above 60%. Due to exposure to high temperatures workers develop heat rash, heat cramps heat exhaustion, or heat stroke which can cost workers life.

Employees should take additional efforts to prevent heat stress, especially while working in warm weather or outside. When people cannot control their internal body temperature, they become ill from it. Sweating is a natural method to cool down in hot weather. Sometimes, sweating alone isn’t enough. A very sweaty workout, excessive heat, and little to no ventilation are examples of such scenarios. Medical conditions and medications may also reduce a person’s tolerance to heat.

heat stress

Here are some of the reasons heat illnesses can occur in workplaces. 

  • High temperature 
  • Extreme humidity 
  • Direct exposure to the sun
  • Intense physical labor
  • Sudden exposure to hot work environments
  • Low intake of liquid 
  • Heavy or waterproof clothing

Heat stress symptoms

Here are some symptoms that can show if a worker is suffering from heat exhaustion. 

  • Weakness
  • Wet skin
  • Irritability
  • Confusion
  • Thirst
  • Nausea
  • Vomiting

Heat-related dangers

Here are some dangers related to heat exhaustions and stroke. 

  • When sweat glands are not functioning freely, it causes skin discomfort. Wear clothes that allow sweat to evaporate and take frequent breaks to help your skin dry and so prevent heat stress.
  • Dehydration results from perspiration. Salt deficiency causes muscle spasms and cramps. Drinking water and salt refills will assist you.
  • Symptoms such as weariness, headache, dizziness, and nausea can occur when a considerable volume of fluid (and sometimes salt) is lost. You’ll want to stay hydrated, replace salt, and rest frequently. Heat exhaustion can be a sign of impending heat stroke.
  • Excessive heat raises the human body’s temperature considerably. If it gets too high, the body’s natural cooling process fails. It also results in dried skin and skin burns. In this situation, first-aid should be administered immediately. Move the victim to a cool environment and fan vigorously until help arrives.

Prevention from heat stress

Several heat stress preventions exists that can lessen the effect of this condition. Knowing the signs and symptoms of heat stress provides the opportunity to take action. Also, in outdoor workplaces, it is better to work in teams rather than individually. This will ensure that if a worker suffers from heat stress, there will be someone available to help. Having a regular outdoor exercise routine can also be extremely beneficial for combatting heat stress. Such activities allow our bodies to acclimatize to warm weather allows them to better cope with excessive heat conditions. 

heat stress

Here are some of the best ways to prevent heat-related health issues. 

  • Develop a comprehensive heat illness prevention initiative.
  • Conduct training on heat stress hazards and prevention measures.
  • Make sure there’s an ample supply of cool water near workstations, providing at least one pint per hour.
  • Adjust work schedules, incorporating frequent rest periods and water breaks in shaded or air-conditioned areas.
  • Gradually ramp up workloads and allow more breaks for new or returning workers to acclimatize to the heat.
  • Assign a dedicated individual to monitor conditions and safeguard at-risk workers from heat stress.
  • Evaluate the use of cooling protective clothing options.
  • Adjust work schedules for more frequent rest periods in shaded or air-conditioned areas.
  • Gradually increase workloads and provide additional breaks for new or returning workers to adapt to heat.
  • Designate a responsible monitor to protect workers at risk of heat stress.
  • Explore cooling protective clothing options. 

How to respond to heat-related sickness?

Here’s what you need to do if one of the workers falls ill due to heat-related reasons.

  • Contact a supervisor or dial 911 if unavailable.
  • Stay with the worker until assistance arrives.
  • Transfer the worker to a cooler/shaded spot.
  • Assist in removing outer clothing.
  • Fan and mist the worker with water, and apply ice packs or towels.
  • Offer cool drinking water if the worker is able to drink.


Take your time adjusting to the heat and humidity. A heatwave strains your body. Reduce your exercise until you get used to the heat, and you will have more stamina. Adjusting to difficult conditions may take days or weeks. Gradual adaptation increases workers’ capacity to sweat, which cools the body and helps maintain a stable temperature.

Headache, dizziness, lightheadedness, fainting, weakness, malaise, mood change, mental disorientation, and nausea or vomiting are all symptoms of heat-related sickness. If you display any of these symptoms, go to the hospital immediately.

To conclude the final thoughts, it is advised that workers complete their OSHA 30 construction training to learn the skills that should be incorporated to protect their health and safety.