When compared to the health crises and community tragedies our country has been through in the past few months, summer heat sounds harmless. But it’s not. Every year otherwise healthy people die or become seriously ill because they did not take adequate steps to protect themselves and their coworkers in advance of rising temperatures. The “in advance” is crucial because one of the symptoms of overheating is disorientation and loss of judgment rendering even the most safety-conscious person at risk. This is why a little knowledge, advance preparation, and attentiveness to the health of yourself and coworkers saves lives.


As temperatures rise, so does our chance of sustaining some type of heat illness. Heat exposure can occur indoors or outdoors, and during any season if the conditions are right. Heat illness is a serious condition that occurs when the body is not able to cool itself. This results in an increase in core body temperature, which can lead to a range of heat-related symptoms, from treatable to potentially fatal.

All site personnel should know how to protect themselves, and others, from heat-induced illness, as well as to recognize and respond to symptoms. Heat intolerance affects everyone differently. 


Environmental conditions that contribute to heat illness include more than just working in the sun or hot temperatures. It is often a combination of factors, such as high temperatures, high levels of humidity and low air movement, that are the most dangerous. Be aware of your current working conditions as well as the expected changes over the course of the day or your shift and prepare accordingly. 

Be sure to know your personal risk factors, including overall health and fitness, and any medications you’re taking which predispose you to heat-related illnesses. Those at greatest risk include workers who are 65 years old or older, overweight, ill, or taking certain medications or supplements. Additional risk factors include fever, dehydration, heart disease, poor circulation, and sunburn. Alcoholic beverages, coffee, tea, or other drinks containing caffeine will dehydrate the body and increase the risk of heat illnesses.

Adapting your body to higher working temperatures is a gradual process and especially important at the beginning of the summer season, and when returning to work after a prolonged absence or recent illness. Depending on conditions, acclimation can range from two to 10 days. And workers should be aware that dark-colored clothing and the use of certain personal protective equipment (PPE) can increase the risk of heat-related illness.


The Occupational Safety and Health Administration (OSHA) has a Heat Illness Prevention educational campaign, with an easy-to-follow safety message: Water. Rest. Shade. 

Proper hydration is essential to preventing heat-related illness, with dehydration being the single biggest cause. Workers should start drinking water one or two days BEFORE working in excessive heat. If you wait until you feel thirsty, it may already be too late. To stay hydrated on the job, OSHA recommends drinking water every 15 minutes. A good rule of thumb is to drink four cups (32 oz.) of water every hour. And remember, caffeinated beverages will dehydrate your body and increase your risk. 

When heat stress is high, taking regular breaks in a shaded area is essential to staying healthy. The length and frequency of these breaks will depend on a variety of factors, including environmental heat, your physical activities, and your personal risk factors. The availability of cooler, shaded locations, such as an air-conditioned building or vehicle, will help you cool down faster and recover more quickly. 


When your body is exposed to excessive heat there will be a physiological response. It’s important to know the signs of each heat-related illness and be prepared to administer treatment. In all cases, workers should alert their supervisor to any suspected heat-related illness in themselves or a team member and be ready to call 911 if needed. It’s also important to be able to describe any signs or symptoms to medical personnel.

Heat Rash is the most common problem in hot, humid work environments. It is also known as prickly heat and is caused by sweat that doesn’t evaporate from the skin. 

  • Symptoms include a sudden rash where the skin has been continuously wet. 
  • Resting in a cool, shaded area and keeping your skin dry will help prevent this condition.

Heat Cramps are the first indication of illnesses related to heat. This is caused by a loss of body salts and fluids during sweating. 

  • Symptoms include severe muscle spasms and cramps, which may occur during or after work hours and typically affect the muscles most used in performing work (arms, legs, or abdomen). 
  • This condition may be relieved by increased salt intake. 
  • Persons with heart problems or those on a low sodium diet who work in hot environments should consult a physician about what to do under these conditions.

Unfortunately, the signs and symptoms of heat exhaustion and heatstroke are not necessarily specific to each condition, nor is there a systematic order of appearance. When in doubt, call 911.

Heat Exhaustion requires immediate medical attention but is not usually life-threatening. Heat exhaustion can quickly become a medical emergency so it’s important to administer aid as soon as possible. Heat exhaustion is caused by the body’s response to the loss of water and salt from heavy sweating. 

  • Symptoms can include headache, weakness, clammy skin, pale or flushed complexion, a rapid pulse, and nausea. In more serious cases, the victim may vomit or lose consciousness. 
  • If heat exhaustion is suspected, move the individual to a cool environment, remove excess clothing, elevate his or her legs, and provide fluids. Water should be consumed in small doses, as long as there is no vomiting or loss of consciousness. The individual’s condition should improve fairly quickly.
  • Persons with heart problems or those on a low sodium diet who work in hot environments should consult a physician about what to do under these conditions.

Heat Stroke is a medical emergency requiring the individual to be cooled down as soon as possible. Call 911. Heatstroke can result in death. The body is no longer able to regulate its core temperature. Sweating stops so it can no longer rid itself of excess heat.

  • Symptoms can include hot or wet skin, confusion, a high temperature (103° or higher), a rapid pulse, possible unconsciousness, and seizures.
  • Any person with signs or symptoms of heatstroke requires immediate medical attention but the cooling process must be started first. This includes moving the individual to a cool environment, removing excess clothing, elevating their legs, and providing fluids. Using cold compresses, thoroughly soaking their clothing with water, and vigorously fanning the body can also aid in the cooling process. 


By taking a few simple precautions – Water. Rest. Shade – and by knowing the warning signs, you can help protect yourself and your co-workers from heat-related illnesses. 

For more information on heat illness prevention and treatment, visit the Occupational Safety and Health Administration (osha.gov) or the Centers for Disease Control and Prevention (cdc.gov).  

OSHA Heat Illness Factsheet: https://www.osha.gov/SLTC/heatillness/3422_factsheet_en.pdf

This article provides a basic understanding of heat-related illnesses. It does not offer any medical advice. Consult your physician for more information regarding heat illness.