California law requires employers to protect workers from heat illness in both outdoor and indoor workplaces, and Cal/OSHA is actively monitoring compliance as temperatures rise. Here's what the rules require - and how to stay ahead of them.
Outdoor Workplaces
Temperature thresholds:
80°F: Basic prevention measures kick in
95°F: "High-heat procedures" required
Key requirements:
Water: Fresh, cool drinking water must be provided
Shade: Required when temperatures exceed 80°F; must accommodate all workers on rest breaks and be as close as practicable to work areas
Rest breaks: Workers can request cool-down rests whenever needed; at 95°F+, agricultural workers must get at least 10-minute cool-down rests every 2 hours
Monitoring: Employers must track temperatures and open shade structures once 80°F is exceeded
High-heat procedures (95°F+): Enhanced observation, pre-shift safety meetings, reminding workers to drink water and take breaks
Indoor Workplaces
Temperature threshold:
82°F: Standard applies when indoor temperatures reach this level
Key requirements:
Cool-down areas: Must be kept below 82°F and large enough for workers on breaks; must be shielded from radiant heat sources
Water: Readily accessible cool drinking water
Assessments: Employers must measure temperature and heat index, recording whichever is greater when reaching 87°F (or 82°F for workers in restrictive clothing or high radiant heat areas)
Control measures: Engineering controls (ventilation, AC), administrative controls (scheduling, rotating jobs), and personal protective equipment as a last resort
Observation: Close monitoring during acclimatization periods
Universal Requirements (Both Standards)
Written Heat Illness Prevention Plan
Employee and supervisor training on heat illness recognition, prevention, and emergency response
Acclimatization procedures for new/unaccustomed workers
Emergency response procedures for workers showing symptoms of heat illness
With Southern California experiencing a heat wave this week, it’s important to help your employees be safe and stay off the radar of Cal/OSHA!
You can download a Heat Illness Prevention Plan template below.)