What is Heat Stress?

Maybe this is too obvious to some people, however, it does help to have a better understanding about this concept and how we deal with it in the workplace.  Heat stress is a set of conditions where the body and its cooling system are under stress from overheating.  Heat stress occurs when the body’s means of controlling its internal temperature starts to fail.  High temperatures, humidity, heavy workloads, decreased air movement, lack of shading from direct heat and the type of clothing worn are all significant factors that induce heat stress.

Heat exposures may be reduced by several methods.  Selection of appropriate workplace controls will vary, depending on the type of workplace and other factors.  Some measures may include:

 Engineering Controls

• Control the heat at its source through the use of insulating and reflective barriers (e.g. insulate furnace walls).
• Exhaust hot air and steam produced by operations.
• Reduce the temperature and humidity through air cooling.
• Provide air-conditioned rest areas.
• Provide cool work areas.
• Increase air movement if temperature is less than 95°F with fans.
• Reduce physical demands of work task through mechanical assistance.

Administrative Controls

• The employer should assess the demands of all jobs and have monitoring and control strategies in place for hot days and hot workplaces.
• Increase the frequency and length of rest breaks.
• Schedule strenuous jobs to cooler times of the day.
• Provide cool drinking water/electrolyte drinks near workers and remind them to drink a cup every 20 minutes or so (do not wait until you feel thirsty!).
• Caution workers to avoid direct sunlight (when possible).
• Assign additional workers or slow down the pace of work.
• Consider job rotation to keep workers fresh.
• Make sure everyone is properly acclimatized.
• Train workers to recognize the signs and symptoms of heat stress and start a “buddy system” since people are not likely to notice their own symptoms.
• Pregnant workers and workers with a medical condition should discuss working in the heat with their doctor.
• First Aid responders and an emergency response plan should be in place in the event of a heat-related illness.
• Investigate any heat-related incidents.

Personal Protective Equipment

• Light summer clothing should be worn to allow free air movement and sweat evaporation.
• Outside, wear light-colored clothing.
• In a high radiant heat situation, reflective clothing may help.
• For very hot environments, air, water or ice-cooled insulated clothing should be considered (Vortex coolers for airline systems).
• Vapor barrier clothing, such as chemical protective clothing, greatly increases the amount of heat stress on the body, and extra caution is necessary.
• Cooling wraps and bandanas can draw excess heat off your neck and head area.

This entry was posted on Wednesday, June 17th, 2009 at 7:45 am and is filed under Safety Articles. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.