When the human body is unable to maintain a normal temperature, heat-related illnesses can occur and may result in death. The Occupational Safety and Health Administration (OSHA) recommends the following work practices to prevent worker illness caused by heat.
- Train workers and supervisors about the hazards leading to heat stress and ways to prevent them.
- Allow workers to get used to hot environments by gradually increasing exposure over a five-day work period. Begin with 50 percent of the normal workload and time spent in the hot environment and then gradually build up to 100 percent by the fifth day. New workers and those returning from an absence of two weeks or more should have a five-day adjustment period.
- Provide workers with plenty of cool water in convenient, visible locations close to the work area. Water should have a palatable (pleasant and odor-free) taste and water temperature should be 50-60°F if possible.
- Remind workers to frequently drink small amounts of water before they become thirsty to maintain good hydration. Simply telling them to drink plenty of fluids is not sufficient. During moderate activity, in moderately hot conditions, at least one pint of water per hour is needed. Workers should drink about six ounces or a medium-sized glass-full every 15 minutes. Instruct workers that urine should be clear or lightly colored.
- Be aware that it is harmful to drink extreme amounts of water. Workers should generally not drink more than a total of 12 quarts of fluid in 24 hours.
- Reduce the physical demands of the job, such as excessive lifting, climbing, or digging with heavy objects. Use mechanical devices or assign extra workers.
- Monitor weather reports daily and reschedule jobs with high heat exposure to cooler times of the day. When possible, routine maintenance and repair projects should be scheduled for the cooler seasons of the year.
- Schedule frequent rest periods with water breaks in shaded or air-conditioned recovery areas.
- Workers are at an increased risk of heat stress from personal protective equipment (PPE), especially from wearing semi-permeable (penetrable) or impermeable clothing (such as Tyvek or rubber), when the outside temperature exceeds 70°F, or while working at high energy levels. These types of clothing materials trap heat close to a worker’s body. Workers should be monitored by establishing a routine to periodically check them for signs and symptoms of overexposure.
Source: OSHA Fact Sheet: Protecting Workers from the Effects of Heat, April 2011, Occupational Safety and Health Administration, http://www.osha.gov.