A new emergency regulation to protect outdoor workers in California from wildfire smoke is in effect until Jan. 28, 2020. According to a Cal/OSHA press release (PDF), the regulation applies to workplaces where the current Air Quality Index (AQI) for airborne particulate matter, or PM 2.5, is 151 or greater and where employers should “reasonably anticipate that employees could be exposed to wildfire smoke.”  The new regulation requires employers to identify harmful exposure to airborne particulate matter from wildfire smoke at the start of each shift and periodically thereafter by checking the AQI for PM 2.5 in regions where workers are located. Employers must reduce harmful exposure to wildfire smoke by relocating work to an enclosed building with filtered air or to another outdoor location where the AQI for PM 2.5 is 150 or lower. If employers cannot reduce workers’ exposure to wildfire smoke so that the AQI for PM 2.5 is 150 or lower, they must provide respirators to all employees for voluntary use. Employers must also provide training on the new emergency regulation, the health effects of wildfire smoke, and the safe use and maintenance of respirators. In the past two years wildfires in California have dramatically increased in number and intensity. The 2018 Camp Fire was the deadliest and most destructive wildfire in the state’s history, killing 86 people and destroying more than 18,000 structures.  More information on the emergency regulation, including rulemaking documents, is available from the website of the California Department of Industrial Relations. Guidance from DIR on protecting outdoor workers exposed to smoke from wildfires is also available.