July through August are dangerous months for heat. Don't be fooled into thinking you can always do the same work at the same intensity in high heat.
At minimum, work in high heat requires regular hydration combined with cooling breaks.
Heat exhaustion is caused by loss of water, sometimes through excessive sweating. This dehydration causes muscle cramps, weakness, and vomiting.
When symptoms of heat exhaustion arise, move the person to an air-conditioned area, even a car, and give small sips of water. Remove some clothing to increase air circulation. A cool mist or even a cool cloth can help.
Heat stroke is the most serious disorder. Skin becomes hot and dry. The body temperature rises. The victim may feel dizzy and confused, or even hallucinate.
Heat stroke is an emergency. Call an ambulance immediately. While waiting for help, get the patient to an air-conditioned space, soak clothing with cool water, and sponge cool water on the face and arms.