FORT CAMPBELL, Ky. – The current heat wave scorching most of the nation makes for dangerous outdoor conditions, said Nita Hackwell, environmental health technician, Preventative Medicine and Environmental Health at Blanchfield Army Community Hospital.
To reduce the likelihood of heat-related injury or illness, Soldiers, Families and civilians can take a few steps to protect themselves, Hackwell said.
One way residents can avoid heat-related emergencies is by understanding what they’re up against when they go outside, she said.
Knowing what to expect and whether it’s advisable to be outside can help in planning activities and determine how much water to drink or bring along.
Contacting the Fort Campbell Heat Line at 270-798-4328 and getting a read on the temperature is one way to do that.
“The Heat Line provides the wet bulb globe temperature [WBGT] index and heat category to members of the Fort Campbell community training, working and playing outdoors in direct sunlight,” Hackwell said. “Monitoring the WBGT index is an important step in determining when modifications to outdoor physical activity should be made to prevent heat-related illnesses.”
Unlike the heat index, which measures temperature and humidity in shady areas, the WBGT factors the effect of direct sunlight into the temperature. The result is a more accurate reflection of what personnel will experience while training.
“The WBGT combines temperature, humidity, wind speed, sun angle and solar radiation [cloud cover],” she said. “The dry bulb is used to measure the ambient air temperature, the wet bulb is used to measure relative humidity and air flow and the black globe indicates the radiant heat exposure in direct sunlight.”
The WBGT index is provided by the Environmental Health Section of BACH’s Department of Preventive Medicine hourly 7:30 a.m.-4 p.m. Mondays-Fridays, excluding holidays, when the air temperature is expected to exceed 75 degrees, Hackwell said.
After hours the WBGT index can be obtained by calling Range Control at 270-798-3001.
“Because the WBGT index can vary at other locations and above different types of surfaces – grass, asphalt, etc. – the WBGT index provided by Environmental Health and Range Control should only be used as a guideline and the WBGT should be measured at the same place outdoor activities are occurring,” Hackwell said.
Heat categories and exercise
The WBGT is used to calculate heat categories, which determine the length of time exercise should be performed and fluid consumption necessary to cope with the temperature.
“Heat categories range from 1-5,” Hackwell said. “As the WBGT index rises, it can become more difficult for the body to cool itself correctly, which can result in conditions such as dehydration, heat cramps, heat exhaustion, and heat stroke. The WBGT index is increased by 5 degrees when wearing body armor and by 10 degrees in MOPP 4.”
Mission oriented protective posture, or MOPP, is personal protective equipment, or PPE, worn by troops in contaminated environments and significantly increases the body’s core temperature when worn in hot weather.
Exercising in extreme heat without having properly hydrated can lead to dangerous health conditions, said Gabriel Gamez, environmental health technicia, Preventative Medicine and Environmental Health, BACH.
“Losing 4% of body weight due to dehydration degrades physical performance by 50%, which can happen in just two hours,” Gamez said.
To reduce the risk of heat-related illness or injury, Fort Campbell personnel should consult the Work/Rest and Water Consumption Table to measure how much water per hour to consume and to follow appropriate rest times, Hackwell said.
The Work/Rest and Water Consumption Table can be found at https://home.army.mil/campbell/index.php/heat-category.
“As the WBGT index raises, physical intensity should be reduced and fluid replacement should increase,” she said. “The Work/Rest and Water Consumption Table provides recommendations for work/rest cycles and water intake for each heat category and intensity of work – easy, moderate and hard.”
Heat-related illnesses include heat rash, sunburn, heat cramps, heat exhaustion, and heat stroke, according to the Centers for Disease Control and Prevention.
“Symptoms of heat exhaustion include dizziness, headache, nausea, weakness, clumsy or unsteady walk, and muscle cramps,” Gamez said. “Heat stroke presents as an altered mental status, profuse sweating, convulsions and chills, stumbling, vomiting, confusion, mumbling, combative behavior, and passing out, or [falling] unconscious.”
The CDC recommends immediately moving to a cooler area if experiencing heat exhaustion or cramps and to seek medical care if someone is suspected of experiencing heat stroke.
For more guidance on heat-related injuries and illness, call BACH Preventative Medicine at 270-956-0100, 270-956-0202, or 270-956-0114.