#232 Heat Acclimatization

  • Acclimatization is the process by which the body adjusts to physical activity in hot weather. The body needs time to adapt to the increased heat and humidity, especially when one is engaged in the heavy physical exertion that happens on a construction jobsite.
  • The 2006 Cal/OSHA Heat Illness case studies revealed that most of the heat illness deaths involved new employees who were on the job only 1 to 4 days.
  • Heat Cramps, Heat Exhaustion, Fainting, Heat Stroke and Death can occur when employees are unaccustomed to working in hot or humid weather.
  • Cal/OSHA recommends an acclimatization schedule where employees begin by spending at least 2 hours of work per day in the heat and increasing time in the heat to a full work shift and pace over a period of 4 to 14 days.
  • Acclimatization strategies for very hot days also include:
  • Timing shifts so that more work can be done during the cooler parts of the day
  • Increasing the number of water and rest breaks
  • Using the buddy system so that workers and supervisors can monitor each other
  • Reminding employees of the cooling benefits of loose fitting, light colored clothing and a wide brimmed hats