Heat stroke is a life-threatening condition, usually associated with a temperature above 104 degrees. The body loses its ability to regulate temperature, Mobley said, so temperature could “be all over, especially if someone turns up the air conditioner.” Victims of heat stroke may lose consciousness and mortality rate can be as high as 50 percent. “Heat stroke is pretty rare.

“It’s important to get the temperature down.” Brain damage may occur as well as damage to internal organs. Severity of damage depends on the amount of time the temperature remains above 104. “Pour water over the victim, fan him, remove clothing and get him in the shade. If possible, get emergency personnel quickly; otherwise, transport to the emergency room. This is a big deal emergency.”

If someone stops sweating “he could be close to heat stroke.”

Prevention is crucial. Workers who spend a lot of time outdoors during hot weather should make a habit of drinking water every time they take a break. “When you stop doing something, take a drink,” he said. “Also, use the buddy system. Have every employee teamed up with another.”

Mobley was a military doctor and saw many cases of heat related illness. The “battle buddy” system was standard protocol for the military, he said, even for commanding officers.

Risk factors for heat illness include acclimatization. “Acclimatization occurs after a person works in the heat for awhile,” he said. “It takes five days to start the process. After 14 days it is completed. With new workers, watch them closely.”

He recalled a case of a young man brought to the hospital in a coma. “He had recently moved to Texas from Minnesota and worked as a roofer. He was 24 years old.”

Shortly after he started work he began to feel bad, mentioned a headache but continued to work. When he went home he took a shower and then went to sleep. “His friends came by two hours later and found him in a coma. He had heat stroke, and his body had lost its ability to control temperature.” Mobley said the young man’s temperature had dropped into the 80s. He did recover.