For some, avoiding the bad air by staying indoors isn't an option.
Many construction and agricultural workers were on the job outdoors Friday.
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Cal/OSHA's Protection from Wildfire Smoke standard requires employers to protect workers from unhealthy air due to wildfire smoke.
If the Air Quality Index, or AQI, for PM 2.5 (particulate matter with a diameter of 2.5 micrometers or less), rises above 151, employers must make accommodations. Those include moving work to a location with healthier air, adjusting duties or schedules to reduce exposure, and providing masks.
"Above 151, they need to offer respiratory protection, such as an N95, for voluntary use," said Edgar Gonzalez with Cal/OSHA's Agricultural Enforcement Task Force. "But prior to that, they should educate their employees on what they're going to do when conditions start rising, what the air quality index means, and what rights employees have to ask for such protections."
When the AQI for PM 2.5 exceeds 500, respirator use is required.
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Heather Heinks with the Valley Air District said it's important for everyone to pay attention to smoke, regardless of the AQI.
"If you can smell it, regardless of what our monitor says, it is impacting you," Heinks said. "Smoke travels in plumes. It could easily miss a monitor and hit a neighborhood. So trust your instincts first and foremost. And yeah, there's probably not a good time to go outside in a given day unless you're checking air quality to see what conditions are."
Daily air quality forecasts and more information can be found on the Valley Air District's website.
In California, it is illegal for employers to retaliate against workers for refusing to work in unsafe conditions, including in evacuation zones.
If you have concerns about your employer, Cal/OSHA says you can submit an anonymous tip.
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