Protection from Wildfire Smoke
Warehouse worker working in smokey air.

Requirements to Protect Workers

Employers in California must protect workers from workplace hazards, including unhealthy air from wildfire smoke.

Cal/OSHA's Protection from Wildfire Smoke standard requires employers to be prepared to protect workers from unhealthy air due to wildfire smoke.

The Protection from Wildfire Smoke standard applies to most workplaces, with some exceptions.

The standard applies to workplaces where:

  1. The current Air Quality Index (AQI) for PM2.5 is 151 or greater, and
  2. The employer should reasonably anticipate that employees may be exposed to wildfire smoke.

The following workplaces and operations are exempt from the standard:

  • Enclosed buildings or structures where the air is filtered by a mechanical ventilation system and the employer ensures that windows, doors and other openings are kept closed, except when it is necessary to open doors to enter or exit.
  • Enclosed vehicles in which the air is filtered by a cabin air filter and the employer ensures that windows, doors and other openings are kept closed, except when it is necessary to open doors to enter or exit the vehicle.
  • The employer demonstrates that the concentration of PM2.5 in the air does not exceed a concentration that corresponds to a current AQI of 151 or greater by measuring PM2.5 levels at the worksite with a direct-reading instrument in compliance with Cal/OSHA requirements.
  • Employees exposed to a current AQI for PM2.5 of 151 or greater for a total of one hour or less during a shift.
  • Firefighters engaged in wildland firefighting.

For questions about how the Protection from Wildfire Smoke standard applies to a workplace, contact Cal/OSHA's Call Center with representatives available in English and Spanish during business hours. Call 833-579-0927.

When wildfire smoke might affect a worksite, employers must monitor the local Air Quality Index (AQI) for PM2.5 before and throughout the work shift. It is easy for employers to track the AQI using websites like the U.S. EPA's AirNow or local air quality management district websites.

Employers can also use their own instruments to measure PM2.5 at a worksite with a direct-reading instrument in compliance with Cal/OSHA requirements.

Read about what employers should do if the air is unhealthy due to wildfire smoke.

The air is considered unhealthy for everyone if the current air quality index (AQI) is 151 or greater for PM2.5.

The small particulates (PM2.5) can present a significant health hazard for workers exposed to wildfire smoke. The greatest hazard to workers is from breathing in these tiny particles, which can cause health problems like coughing, difficulty breathing, reduced lung function and worsening heart and lung conditions.

If the air is unhealthy due to wildfire smoke, employers must take steps to protect workers from the harmful effects of the smoke.

Read about the steps employers must take to protect workers from wildfire smoke.

If the local Air Quality Index (AQI) for PM2.5 is 151 or greater, employers must take these steps to protect workers:

  • Communication – Inform employees of the AQI for PM2.5 and the protective measures available to workers.
  • Training and instruction – Provide effective training and instruction to all employees on the information in section 5141.1 Appendix B. (Read more in the section Training and communication)
  • Modifications – If feasible, implement modifications to the workplace to reduce exposure. Examples include providing enclosed structures or vehicles for employees to work in, where the air is filtered.
  • Changes – Implement practicable changes to work procedures or schedules. Examples include changing the location where employees work or reducing the time they work outdoors or exposed to unfiltered outdoor air.
  • Respiratory protection – Provide proper respiratory protection equipment, such as disposable respirators for voluntary use, according to the details below:
    • To filter out fine particles, respirators must be labeled N95, N99, N100, R95, P95, P99, or P100, and must be labeled as approved by the US National Institute for Occupational Safety and Health (NIOSH).
    •  Read more about N95 respirators for wildfire smoke protection

If the air is unhealthy due to wildfire smoke and work cannot be moved to a location where the air is not harmful, employers must provide proper respiratory protection, like N95 respirators.

Workers can voluntarily choose to use the respirator if the Air Quality Index (AQI) for PM2.5 is from 151 to 500. If the AQI for PM2.5 exceeds 500, respiratory protection is required and employers must implement additional steps including fit testing and medical evaluation for workers to use the respirators.

If employers provide respiratory protection for voluntary use, they must also provide workers information about the use of respirators. Employers can provide this information from either the Wildfire Smoke Protection standard Appendix B or the Respiratory Protection standard Appendix D.

Employers can also provide additional training, such as Cal/OSHA's video on the use of N95 respirators.

When the Protection from Wildfire Smoke standard applies to a worksite, employers must provide workers training and instruction based on the information in Appendix B. This training includes information on:

  1. The health effects of wildfire smoke
  2. The right to obtain medical treatment without fear of retaliation
  3. How employees can obtain the current Air Quality Index (AQI) for PM2.5.
  4. The employer's method to communicate with workers about the Air Quality Index and protections available to workers
  5. The importance, limitations, and benefits of using a respirator when exposed to wildfire smoke

Training must be provided to workers in a language they understand. Employers can use different methods to make training effective, including Cal/OSHA's Training Resources and videos on YouTube.

You can call 833-579-0927 to connect with a live Cal/OSHA representative between the hours of 9 am and 7 pm to ask questions related to health and safety in the workplace. Bilingual representatives are available to provide information on topics like COVID-19, heat illness prevention, and wildfire smoke.

Invite Cal/OSHA to an event, or request a presentation or educational training by submitting an Outreach Request Form.

February 2023