It’s heating up—New indoor heat illness standards are nearing completion

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In recent years, Cal-OSHA has modified and refined heat illness prevention requirements for outdoor work areas. Now, employers will be facing new Cal-OSHA requirements for indoor work areas. In the past several months, the Cal-OSHA Board (“Board”) has issued multiple rounds of revised standards on Indoor Heat Illness Prevention, with public comment on the most recent revisions closing on November 28, 2023. The Board is scheduled to vote on the latest version in early 2024.

These standards would apply to indoor work areas where the temperature is at or above 82 degrees Fahrenheit when employees are present.

Some of the measures that employers would have to implement to protect workers from indoor heat illness include:

  • Implementing a written indoor heat illness prevention program in addition to an outdoor heat illness prevention program;
  • Monitoring weather and temperature conditions and adjusting working conditions and practices as appropriate;
  • Providing breaks for cooling down and acclimatization;
  • Providing access to drinking water, to cool down areas, and preventative cool down rest periods;
  • Implementing administrative or structural controls to reduce heat exposure, such as providing air conditioning or ventilation systems; and
  • Providing employee training.

The most recent modifications include the following clarifications:

  • Compliance is not required for incidental heat exposures where an employee is exposed to temperatures above 82 degrees for less than 15 minutes in any 60-minute period.
  • Measuring temperature and heat index is to be done where employees work and at the times during the work shift when employee exposures are expected to be the greatest.
  • Indoor heat illness prevention may be added to training pertaining to heat illness prevention for outdoor employment where employees are affected by both.

These new standards are set for vote in time for possible implementation by the hot summer months in 2024. We will provide updates with further developments.