While the hot days of summer are a welcome relief after a cold and snowy winter, they can be bittersweet for employees who work in hot conditions. That is because this group of workers has a high risk of experiencing a heat stress-related illness.
Heat stress is a term that includes the various negative health effects that are caused by exposures to excessive heat. It is occurs when the mechanisms that keep our bodies cool and at a set core temperature of 98.6 degrees Fahrenheit are disrupted.
In brief, excess heat in our bodies is dissipated primarily by 2 different processes. The first involves increasing the blood flow to the skin, then cooling it in a process called radiative heat loss. This process works well when the temperature of the surrounding air is less than the temperature of the skin.
The second process involves the production of sweat and the resulting evaporation of that sweat off of the skin. This process is most efficient when the humidity is relatively low and there is air movement across the skin (ie, a breeze or ventilation provided by a fan).
As you can see, the risk of heat stress increases on hot, humid days when there is limited air movement. Employees who wear multiple layers of clothing and/or personal protective equipment such as respirators, hard hats, and coveralls have an increased risk of experiencing heat stress, as do older individuals and people who are obese or have cardiac conditions or high blood pressure. When is it too hot? Here is a chart provided by OSHA depicting risk level.
Heat stress is a cumulative process that first presents itself as a relatively minor heat rash. If the employee ignores or tolerates the heat rash and continues to work in the hot environment his or her symptoms can progress to heat cramps which produce muscle spasms and/or pain. Once again, if the employee continues to work in this condition then heat exhaustion or heat stroke can occur.
Heat exhaustion is characterized by headache, nausea, dizziness, weakness, and a fast heart beat. Most of these symptoms are the result of heavy sweating and a corresponding loss of body fluids and/or electrolytes. This is a serious condition that requires an immediate intervention. Move the worker to a cool area and give him or her a drink of cool water or a sports drink that contains electrolytes. Watch the employee closely and obtain a medical evaluation if the symptoms do not improve within an hour or so.
Heat stroke is a potentially life-threatening illness in which the core temperature of the body is elevated and the major body organs and processes are seriously impaired. Individuals experiencing heat stroke are confused and may faint or suffer seizures. Immediate medical attention is required if you suspect that a person has heat stroke. Call 911 and treat the victim while you are waiting for the ambulance by moving him or her to a cool location, apply ice packs or compresses, and offering cool water if he or she is conscious.
Currently OSHA has a campaign to prevent heat illness in outdoor workers. Follow this link to the OSHA web page for great heat illness and prevention information https://www.osha.gov/SLTC/heatillness/index.html. There is even a phone App that will provide preventive guidance based upon current weather conditions. Currently the App is available for Android and iPhone.
OSHA - Heat Stress Phone App.
There are many risks to workers when having to perform physically demanding tasks in high heat environments. This is especially true when protective clothing must be worn. A qualified Industrial Hygienist should be consulted to determine appropriate controls and work/rest regimen schedules. If you have any heat related concerns for your employees please let us know through our web form and one of our professional staff will contact you within 24 - 48 hours.