Heat index outlines formula for heat safety

  • Published
  • By Senior Airman William A. O'Brien
  • 39th Air Base Wing Public Affairs
INCIRLIK AIR BASE, Turkey --  To ensure the safety of Airmen working in extreme weather conditions, the 39th Medical Operations Squadron's Bioenvironmental Engineering Element monitors the wet bulb globe temperature.

WBGT is a composite temperature used to estimate the effect of temperature, humidity, wind chill and solar radiation on people.

"We monitor the heat index by tracking ambient air, humidity and radiant heat to establish the heat category," said Senior Airman Sarah Lowry, 39th MDOS Bioenvironmental Engineering Element technician. "The measurement of three different thermometers -- one for the heat for the sun, one for the humidity, one for the dry heat -- is calculated, and the composite temperature is the WBGT."

These calculations are done to determine the heat category. By knowing the heat category and degree of labor being done, Airmen can use the Work/Rest/Water Consumption Table to determine their work/ rest cycle.

"So supervisors can use the chart to know how long they can send people outside for and what they will be able to do while they are out there," said Staff Sgt. Nicole Dunlap, 39 MDOS Bioenvironmental Engineering Element craftsman.

The WBGT here is usually higher than other places because of the value placed on humidity.

"The humidity here makes a big difference because 70 percent of the measurement is based on the humidity, and it's very humid here," said Dunlap.

The purpose of the heat index is to establish the amount of fluid that should be consumed each hour to prevent a heat induced illness.

"To prevent heat illness, be aware of what the heat category is and keep in mind that it's harder for your body to cool itself down in extreme heat," Dunlap said. "If you're working outside, remember to pay attention to the work/rest cycle. The rest periods are different depending on which heat category we are in and for the level of work you are doing, whether it is low, moderate or heavy work."

Another way to prevent heat illness is finding indoor alternatives to outdoor activities or rescheduling things to later in the day when it has cooled down.

"Instead of going outside to run, go to the gym and use a treadmill, (but still) make sure you're taking in the proper amount of fluids," added Dunlap.

If Airmen are outside too long without proper hydration, they will begin to display symptoms of heat illness.

"Heat illness can be identified by dizziness, nausea, vomiting and disturbed vision. A heat stroke can develop if your body is overheating and can't cool down," said Dunlap.
If the early warning signs of heat illness are not identified, the Airman runs the risk of heat stroke.

"If someone is undergoing a heat stroke, have them lie down flat and raise their legs and cool them by removing any excess layers of clothing, spray them with warm water or fan them with warm air and ensure they rehydrate," said Dunlap.

Examples of what constitutes each work level can be found on the Work/Rest/Water Consumption Table.