FACTORS LEADING TO HEAT STRESS

• High temperature and humidity;
• Direct sun or heat;
• Limited air movement;
• Physical exertion;
• Poor physical condition;
• Some medicines;
• Inadequate tolerance for hot workplaces; and
• Insufficient water intake can all lead to heat stress.

WHAT KIND OF HEAT DISORDERS AND HEALTH EFFECTS ARE POSSIBLE AND HOW SHOULD THEY BE TREATED?
Heat Stroke is the most serious heat related disorder and occurs when the body’s temperature regulation fails and body temperature rises to critical levels. It is a medical emergency that may result in death. The primary signs and symptoms of heat stroke are confusion; irrational behavior; loss of consciousness; convulsions; a lack of sweating (usually); hot, dry skin; and an abnormally high body temperature. If a worker shows signs of possible heat stroke, professional medical treatment should be obtained immediately. Until professional medical treatment is available, the worker should be placed in a shady, cool area and the outer clothing should be removed. Douse the worker with cool water and circulate air to improve evaporative cooling. Provide the worker fluids (preferably water) as soon as possible.

Heat Exhaustion is only partly due to exhaustion; it is a result of the combination of excessive heat and dehydration. Signs and symptoms are headache, nausea, dizziness, weakness, thirst, and giddiness. Fainting or heat collapse is often associated with heat exhaustion. Workers suffering from heat exhaustion should be removed from the hot environment and given fluid replacement. They should also be encouraged to get adequate rest, and when possible, ice packs should be applied.

Heat Cramps are usually caused by performing hard physical labor in a hot environment. Heat cramps have been attributed to an electrolyte imbalance caused by sweating and are normally caused by the lack of water replenishment. It is imperative that workers in hot environments drink water every 15 to 20 minutes and also drink carbohydrate-electrolyte replacement liquids (e.g., sports drinks) to help minimize physiological disturbances during recovery.

ADMINISTRATIVE AND/OR WORK PRACTICE CONTROLS TO OFFSET HEAT EFFECTS

• Acclimatize workers
• Replace fluids
• Reduce the physical demands
• Provide recovery areas
• Reschedule hot jobs for the cooler part of the day
• Monitor workers

WHAT PERSONAL PROTECTIVE EQUIPMENT IS EFFECTIVE IN MINIMIZING HEAT STRESS?

• Reflective clothing, worn as loosely as possible, can minimize heat stress hazards.
• Wetted clothing, such as terry cloth coveralls or two-piece, whole-body cotton suits are another simple and inexpensive personal cooling technique. It is effective when reflective or other impermeable protective clothing is worn.
• Water-cooled garments range from a hood, which cools only the head, to vests and “long johns,” which offer partial or complete body cooling. Use of this equipment requires a battery-driven circulating pump, liquid-ice coolant, and a container.

SAFETY REMINDER – STAY HYDRATED AND WATCH FOR THE SIGNS OF A PROBLEM