Environmental risk factors for heat illness include, but may not be limited to:
- Air temperature
- Air movement, or lack thereof
- Humidity
- Radiant heat from the sun and other sources
- Conductive heat sources such as the ground
- Employee workload severity
- Employee workload duration
- Protective clothing and PPE worn by workers
Employers have a duty to protect workers from environmental heat stressors by monitoring workers during high heat periods and mitigating exposures whenever possible.