We're Hot and Unbothered

Liquid or frozen, flavored electrolyte replacements are popular in workplaces around the world. And there are more ways to cool off, too.

• By Jerry Laws
• May 09, 2008

Working a summer job many years ago on a crew of a county road repair department was my first full-time outdoor employment. Flagging for our paving machines and dump trucks that first day was a brutal education, but not because of the pace, the dust, the heat, or the toil. It was rough because I hadn’t known to bring my own jug of water. On Day Two and every work day thereafter, I was much better prepared.

Effective preparation is the key to prevent heat illnesses. Lots of factors can make some people vulnerable—physical condition, medications, choice of clothing, excessive use of alcohol or drugs, and more. And the ambient temperature doesn’t have to reach triple digits for a worker to get in trouble.

Physically fit workers adapt to hot conditions and become acclimatized faster than out-of-shape workers do. While full acclimatization may take up to three weeks of continued physical activity in the hot environment, acclimatization is quickly lost, and a small percentage of workers never will become acclimatized, according to “Working in the Heat,” a 2007 Workplace Health and Safety Bulletin from the Government of Alberta Employment, Immigration and Industry that is an excellent tutorial on this topic.

“Fluids should be located at or near where the work is being done,” the document states. “Workers should be able to get a drink at any time during the workday without going too far from their work area. In some cases a portable hydration system may be helpful. Looking like a small backpack, it can hold up to four litres of fluid and is worn on the back. The wearer takes a drink using the attached long drinking tube and mouthpiece. As a rough guide, workers working under hot conditions should drink approximately 250 ml (1 cup) of fluid every 20 minutes.

“Salt pills are rarely required and their use is not recommended (a person can have too much salt). The normal salt content of the diet, including salt as a seasoning, is usually enough to replace salt lost through sweating. If salt replacement is a concern, try one of the electrolyte replacement drinks diluted to half strength with water.”

Thirst quenchers are popular pretty much everywhere workers are sweating in the heat, said Mike Dalton, marketing manager for Sqwincher Corp. of Columbus, Miss. The company sells its products in the United States, Canada, Mexico, Costa Rica, New Zealand, and Australia, and it had been selling them in South Africa but lost its distributor there, he said, adding that Sqwincher chose those locales because of the similarity in their industrial workplaces.

Sugar-free thirst quenchers are a popular item these days (“We’re trying to attack the diabetes issue in the workplace,” said Dalton), and 3-ounce freezer pops in cherry, grape, orange, lemon-lime, and mixed berry flavors became highly popular roughly four years ago and are going strong, he said. “Steel mills, welding—it seems to be highly popular because they can’t keep water stations local, and they wear so much PPE.”

The freezer pops taste a bit sweeter than the drinks and have a higher electrolyte volume than the same amount of liquid quencher, but otherwise the formulation of the two is the same, Dalton said.

Engineering and Administrative Controls
Engineering controls useful in hot conditions include general ventilation, spot cooling, shielding from radiant heat sources, cooling fans, mechanical refrigeration, and powered equipment to eliminate manual tasks where possible. Administrative controls include providing exposed workers with plenty of drinking fluids, alternating work with longer rest periods in cool areas, scheduling the most strenuous work for cooler periods of the day, and rotating tasks.

Training for hot conditions includes educating workers to recognize and report heat stress disorders before they become serious. Supervisors should consider workers’ physical condition when determining their fitness to work in hot environments, and they should be trained to notice heat stress symptoms and to allow workers to take a break if they become uncomfortable. Employees should be educated about heat illnesses and the necessity of fluid replenishment. They should be able to recognize dehydration, fainting, heat cramps, heat exhaustion, and heat stroke. Some experts recommend advising workers of the importance of daily weighing before and after work to avoid dehydration.

Checking the heart rate of a worker in a hot environment is a valuable tool for controlling heat stress, according to the “Handbook of OSHA Construction Safety and Health” by Charles D. Reese and James V. Eidson (©1999 by CRC Press). They suggest checking heart rates during breaks. If it exceeds 120, work time should be reduced and rest time increased, they recommend.

Someone whose heart rate reaches 127 per minute should work for no longer than one hour without a rest period during which the rate returns to 60-80 per minute, while a rate of 145 means you should work for no more than 15 minutes without a break, Reese and Eidson write.

Heat-Related Health Problems
Heat stroke, the most serious health problem, occurs when the body’s temperature regulatory system fails and sweating becomes inadequate. Body temperature may reach 105 degrees Fahrenheit or more. The victim’s skin is dry and hot; he may be confused and may experience convulsions or lapse into unconsciousness. Prompt, appropriate treatment is essential.

Heat exhaustion happens when someone loses a lot of fluid by sweating. He still sweats but may be fatigued, giddy, or nauseous. His skin is clammy and moist, with body temperature normal or slightly elevated. Treatment usually involves having him rest in a cool place and drink plenty of liquids.

Heat cramps are muscle spasms that may be felt by workers who sweat profusely and drink large quantities of water but do not adequately replace salt loss.

Heat rash can occur in hot, humid environments where sweat is not easily removed from the surface of the skin by evaporation and the skin remains wet most of the time. A skin rash results because the sweat ducts become clogged.

This article originally appeared in the May 2008 issue of Occupational Health & Safety.