Exposure to heat can cause illness and death. The most serious heat illness is heat stroke. Other heat illnesses, such as heat exhaustion, heat cramps and heat rash, should also be avoided. There are precautions that can be taken any time temperatures are high and the job involves physical work.
Risk Factors for Heat Illness
High temperature and humidity, direct sun exposure, no breeze or wind
Heavy physical labor
Low liquid intake
Symptoms of Heat Exhaustion
Headache, dizziness, or fainting
Weakness and wet skin
Irritability or confusion
Thirst, nausea, or vomiting
Symptoms of Heat Stroke
May be confused, unable to think clearly, pass out, collapse, or have seizures (fits)
May stop sweating
To Prevent Heat Illness:
Drink plenty of cool water. At least one pint of water per hour is needed.
Take rest breaks in a cool area.
More information from the Centers for Disease Control and Prevention here.