Even the most effective safety program may overlook how to handle the seasonal concern of heat stress. Typically, employees with occupations that routinely place them in hot environments find themselves subject to heat stress problems more often than those with less severe duties. In environments where an employee is continually subjected to extreme temperatures, he is more likely to experience a reduction in work performance or encounter bodily reactions related to heat stress.

Heat stress takes a toll on workers. Whether it is poor worker performance, an injury or fatality, if heat stress isn’t recognized and managed properly, it will cost both the employer and employee significantly through loss of staff and/or loss of revenue. Put into an economic perspective, the national average cost per worker for a disabling injury is an astounding $48,000 (National Safety Council, “Accident Facts” 2010 edition). This is a $20,000 increase compared to 10 years ago. Simply put, heat stress prevention is cheaper than the alternative.

The best recommendation for handling heat stress is to combat the problem through proper hydration procedures coupled with a well-balanced diet and various other common-sense methods.

Body hydration

One of the most important steps is proper body hydration. Sweat acts as a built-in cooling system for the body. Once perspiration begins, the effects of dehydration have already started. A dehydrated body pulls water and minerals from many locations inside the body to compensate for a lack of vital elements elsewhere. It is key to keep the intake of fluids equal to the amount being released through perspiration or urination throughout the day. An important step to remember is to begin hydrating the body before dehydration starts. This means instructing employees to start each day by consuming a regimen of fluids designed with the sole purpose of keeping the body’s hydration and electrolyte balance stabilized.

A common misconception is that water is the complete solution for hydration. However, when a person perspires, not only is water depleted from the cellular composition, essential mineral salts and electrolytes are depleted as well. These are necessary to keep the body safely balanced throughout a rigorous workday. Electrolyte replacement programs are specifically formulated to promote continuous consumption and prevent muscle cramps by providing essential carbohydrates and minerals for quick body stabilization. These beverages are absorbed significantly faster than water alone, allowing the body to replenish electrolytes and minerals needed for proper rehydration.


Another factor influential in coping with heat stress is a proper diet. The metabolic rate of an individual can add 10 to 100 times more heat to the body than radiation and convection combined. Employees who are exposed to heat should avoid eating heavy or fatty meals during working hours. A person can lose as much as six quarts of fluid daily through perspiration or urination. Entice employees to drink a balanced rotation of water and electrolyte replacement drinks throughout the day. Workers who drink more fluids during work are less likely to eat heavy meals due to a smaller appetite. However, liquids should not take the place of proper eating habits. A well-balanced diet is key to the body’s ability to combat other illnesses besides heat stress.

Minimize caffeine consumption

Reduce the worker’s intake of caffeine-containing beverages and foods. An average cup of brewed coffee contains 80-115 mg of caffeine. On average, a coffee consumer will consume as many as five cups of coffee daily, adding up to 400-575 mg of caffeine consumed daily. The effects of caffeine on workers range from moderate alertness to elevated stress levels, through both anxiety and tension.

Caffeine will affect worker performance. In average doses (more than 200 mg) caffeine can produce common reactions such as trembling, nervousness, chronic muscle tension, irritability and throbbing headaches, to more severe responses like disorientation, sluggishness, depression and insomnia. These reactions are only intensified with the additional element of heat stress.Surprisingly, most people assume that drinking coffee prevents this from happening.

Caffeine can’t make up for declining performance caused by lack of rest or physical exhaustion. Other health problems documented from caffeine use are linked to heart disease, high blood pressure, tension-nervousness and anxiety disorders, as well as a link to bone loss through caffeine interference with the kidney’s ability to absorb calcium, thus increasing its excretion.

Coffee acts as a diuretic. A coffee drinker will have a significant loss of body fluids through increased urination, thus removing minerals essential in keeping his body at a safe working level. In a heat-stressed work environment, it is essential that vital body fluids and mineral salts be replenished.

Common-sense safety

  • When possible, wear loose lightweight clothing
  • Wear hats and other clothing that will protect you from damaging UV exposure
  • Apply sunscreen to protect against skin burns
  • Use personal protective clothing and cooling devices designed to protect against heat and exposure
  • Take frequent breaks in cool, shaded areas
  • Make sure workers are acclimated to their working conditions. (OSHA recommends six days to gradually get used to extreme environments.
Know your employees and their habits. Be certain to keep them informed of the dangers associated with heat stress in their workplace. An acute awareness of the danger signs and a thoroughly managed safety program are key to safely maintaining heat stress.