Are You Prepared? FAQs on Cal/OSHA’s Emergency Wildfire Smoke Protection Regulation

In response to the dangerous levels of air quality last fall after the wildfires in Northern and Southern California, the state Division of Occupational Safety and Health (Cal/OSHA) has enacted an emergency regulation addressing hazardous wildfire smoke exposure.  In addition, at its last advisory committee meeting, Cal/OSHA discussed multiple possibilities for a permanent regulation.  The agency expects to present a 2.0 version of the regulation, which would go into effect after the emergency regulation expires in January 2020, followed by a subsequent version to be released sometime in the future.  Employers should stay up to date on these developments as Cal/OSHA’s requirements are becoming more stringent with each iteration. 

For now, employers should come into compliance with the emergency regulation, if they have not already done so. Some common questions and answers concerning the emergency regulation are listed below.

  1. Is the new regulation limited to outdoor workers only? 

No.  The regulation also applies to indoor workers who work: (a) in an enclosed building or structure without air filtered by a mechanical ventilation system; (b) in an enclosed vehicle without air filtered by a cabin air filter; or (c) in an enclosed building, structure, or vehicle where the employer does not ensure that windows, doors, bays, or other openings are kept closed to minimize contamination by outdoor or unfiltered air. 

  1. If we anticipate exposure to wildfire smoke, and we check the Air Quality Index (AQI) PM2.5 level before the start of every shift, is that  sufficient?   

No.  Employers must determine potential employee exposure to PM2.51 at the beginning of each shift and periodically thereafter.   

  1. We have sensors at our workplace that detect AQI PM2.5 levels from .5 to 2.5 micrometers.  Is this sufficient under the regulation?

No.  An employer can use a direct-reading particulate matter monitor to determine PM2.5 levels, but the monitor must be capable of measuring the concentration of airborne particle sizes ranging from an aerodynamic diameter of 0.1 micrometers up to and including 2.5 micrometers. 

  1. Our business has a main office, but our employees work remotely and their locations vary by job on a daily basis.  Can I just monitor AQI levels at the main office as a reasonable average? 

No, employers must measure AQI PM2.5 levels at the worksite where work is being performed.  However, employers do not need to monitor telecommuting employees who only work from their homes.   

  1. We have an overhead PA system in one of our production facilities that does not have mechanical ventilation.  Will this satisfy our requirement for a communication system in the event of exposure to wildfire smoke under the new regulation?

Standing alone, no.  The communication system has to be two-way so that employees can inform their employers if they notice air quality is getting worse or if they are suffering from any symptoms due to the air quality, without fear of reprisal.  A PA system in combination with another system (e.g., text, email, telephone, open communication in the facility, etc.) that allows employees to communicate to the employer would comply, however.       

  1. Our employees frequently travel outdoors between two main campuses, which provide filtered air.  If the AQI PM2.5 is unhealthy (151 or greater) outdoors, would this regulation apply to those employees even if they work the majority of their time indoors? 

It depends.  The regulation does not apply to workplaces and operations where employees are exposed to unhealthy air (AQI PM2.5 of 151 or greater) for one hour or less during a shift. 

  1. Our employees pick up parts and make deliveries in a 150-mile radius from our main office.  If we reasonably anticipate exposure to wildfire smoke, do we need to constantly monitor the AQI PM2.5 levels for each of these mobile employees? 

No, as long as the employees remain in a vehicle with a cabin air filter and the employer ensures that windows, doors, bays and other openings are kept closed to minimize contamination by outdoor or unfiltered air.  However, the employer should monitor AQI PM2.5 levels at locations where the employee leaves the enclosed vehicle and where the cumulative exposure to unhealthy air (AQI PM2.5 of 151 or greater) is more than one hour (60 minutes) per shift.   

  1. If we provide employees with approved respirators, are we also required to provide medical evaluations, fit testing, and shaving?  And how much does a compliant respirator cost? 

The answer here depends on whether respirator use is voluntary or mandatory.  Employers must provide respirators for voluntary use where the AQI PM2.5 is 151-499.  For voluntary use, medical evaluations, fit testing, and shaving are not required.  Respirator use is mandatory where the AQI PM2.5 is 500 or greater, and the employer must follow the manufacturer’s instructions for medical evaluations, fit testing, and shaving.  A NIOSH-approved N95 particulate filtering face piece respirator costs approximately $12 to $15.

  1. We have male employees who do not shave for religious or cultural reasons.  What do we do if the AQI PM2.5 is 500 or greater? 

You have several options depending on the duration of the exposure to wildfire smoke.  If feasible, you could call off the shift.  Alternatively, you could transfer the employee to indoor work with mechanical ventilation or in an enclosed vehicle with cabin air filtration so long as all windows, doors, and openings are kept closed to minimize contamination by outdoor or unfiltered air.  Finally, you could purchase a loose fitting respirator, which doesn’t require shaving like a tight-fitting respirator.    

  1. I just found out that the AQI PM2.5 levels are above 151 for our workforce today, and I don’t have any approved respirators for voluntary use.  What do I do? 

Employers should plan ahead for this possibility and consider stocking up on enough approved respirators to cover the workforce for several days.  N95 respirators are often sold at hardware stores and pharmacies, while supplies last.  During last year’s fire season, N95 respirators were also made available at various state and local agencies, which were posted at the California Governor’s Office of Emergency Services or Cal OES webpage (   

See Footnotes

PM2.5 refers to particulate matter suspended in the air with an aerodynamic diameter of less than 2.5  micrometers.

Information contained in this publication is intended for informational purposes only and does not constitute legal advice or opinion, nor is it a substitute for the professional judgment of an attorney.