Cal/OSHA has been working on a proposed Indoor Heat Illness Prevention Standard since 2017. Now, nearly 5 years later, the Cal/OSHA Standards Board published a draft standard and announced a public hearing on Heat Illness Prevention in Indoor Places of Employment. This comes after Cal/OSHA had stepped up enforcement of indoor heat hazards despite no formal standard in place.

While the draft standard released will apply to all indoor work areas where the temperature equals or exceeds 82 degrees, the trigger for employers to initiate additional preventative measures for heat illness protections (including the use of instruments to measure heat index) will be 87 degrees. These proposed measures include the following:

• Opening cool-down areas, which are defined as an indoor or outdoor area that is blocked from direct sunlight and shielded from other high radiant heat sources and is either open to the air or provided with ventilation or cooling.

• Providing each employee with one quart of drinking water per hour.

• Allow employees to take breaks whenever a worker feels the need to rest to protect from overheating.

Similar to the existing outdoor heat illness and injury prevention standard, employers would be required to establish emergency response procedures to treat employees who become ill as well as monitoring new employees for signs of heat stress during their first 14 days of work in hot conditions.

The proposed standard would require both employees and supervisors to be trained on indoor heat illness prevention and safety.

Under the proposed standard, employers would be required to monitor the temperature and heat index inside buildings and keep records of the readings for twelve months or until the next measurements are taken, whichever is later.

The public hearing on the proposed standard is scheduled for May 18, 2023, and written comments may also be submitted until that date.