Heat-Related Illness and Outdoor Workers
UT Health Austin clinicians share tips to help you work smart, stay safe, and beat the heat this summer
Reviewed by: Edward Bernacki, MD, MPH
Written by: Rocky Epstein and Ashley Lawrence
Whether your basking sweltering heat and humidity, cooling off at Barton Springs, or sitting under a porch fan listening to cicadas in the late afternoon, these are all trademarks of a typical Austin summer day. As idyllic as summer seems for most of us, each year, extreme heat and humid conditions affect thousands of outdoor workers, causing a range of heat illnesses.
Common heat-related conditions include:
- Rhabdomyolysis is a serious medical condition characterized by the breakdown of skeletal muscle tissue. This breakdown releases myoglobin, a protein found in muscle cells, into the bloodstream. When myoglobin is released in excessive amounts, it can cause kidney damage or kidney failure. Prolonged periods of exertion in extreme heat can increase the risk of rhabdomyolysis. Common symptoms include muscle pain, cramping, swelling, weakness, and decreased range of motion in the joints.
- Heat exhaustion may precede heat stroke, a much more significant condition. With heat exhaustion, your body’s core temperature may rise to between 100 and 102 °F. Common symptoms include headache, nausea, vertigo, weakness, thirst, heavy sweating, irritability, and a decreased urine output.
- Fainting, or heat syncope, can occur in workers who stand all day or rise suddenly from a seated position, causing a temporary drop in blood pressure. This is often a result of dehydration and lack of acclimation. Common symptoms include light-headedness, dizziness, and feeling faint.
- Heat rash may appear due to restrictive clothing. Tight clothing traps sweat close to the skin. This blocks the sweat glands, causing the sweat to be unable to evaporate. As a result, a red, bumpy rash that give off a prickly or hot sensation will appear. It is important to remove tight or restrictive clothing to let the skin cool and air out.
Acclimating to the heat in the early days of summer is key to preventing heat-related illness. It typically takes two weeks to acclimate to working in the heat. It is important to wear breathable materials that are lightweight, take frequent water breaks, and give yourself time to acclimate to the heat.
Mind the Humidity
Humidity can mean the difference in how quickly a person may recover from heat exposure. When relative humidity is 75%, you cannot count on sweating alone to cool your body. High humid conditions and rising temperatures makes it difficult for a person to cool down. If you or someone you know is suffering from a heat illness on a high humidity day, it is important to cool the whole body down as soon as possible. The fastest way to do this is by submerging the body in a pool or other body of water or by using cooling garments or wet towels to help bring the body temperature down. In less humid conditions, you can use cool compresses, water, or rest in a cool, shaded area.
Most heat-related illnesses occur during the first strong heat wave, primarily because .individuals are unaccustomed to the sweltering temperatures and high humidity. It is crucial to maintain a state of hyper-vigilance, although remaining vigilant at all times is essential.
Ways to stay safe throughout the summer:
- Take time to acclimate to the heat: It usually takes a minimum of two weeks – don’t rush it.
- Dress comfortably: Wear breathable, lightweight, loose-fitting, and light-colored clothing to reflect the heat and keep you cool.
- Take frequent water breaks: Drink 8 ounces of water every 15-20 minutes even if you aren’t thirsty. Drinking at shorter intervals is more effective than drinking large amounts infrequently.
- Avoid working during the hottest part of the day: Optimal timing would be either in the early morning or late afternoon when temperatures tend to be cooler.
Be sure to check the heat index and follow heat safety tips. The Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH) have developed a free downloadable Heat Safety Tool App to help quickly assess the heat index. It also offers heat safety tips to keep you safe during the day.