Cal/OSHA is cautioning California employers to be prepared to protect workers from unhealthy air due to wildfire smoke.

When workers are at risk form unhealthy air from wildfires, California’s protection from wildfire smoke standard requires employers to take steps such as changing the location of work operations, modifying work schedules or providing proper respiratory protection like N95 respirators.

According to CalFire, there have been over 4,000 wildfire incidents so far in California in 2021 and more than 100 structures have been damaged. Smoke from these wildfires contains chemicals, gases and fine particles that can harm health.

One of the most harmful hazards comes from breathing fine particles in the air (called PM2.5), which can reduce lung function, worsen asthma or other existing heart and lung conditions, and cause coughing, wheezing and difficulty breathing, according to Cal/OSHA.