Protecting Outdoor Workers Exposed to Smoke from Wildfires

Please note: This webpage discusses respiratory hazards for outdoor workers such as farm workers and others who work in locations where wildfire smoke can travel. It does not discuss additional respiratory hazards for firefighters and others who work in close proximity to active wildfires.

Smoke from wildfires contains chemicals, gases and fine particles that can harm health. The greatest hazard comes from breathing fine particles in the air, which can reduce lung function, worsen asthma and other existing heart and lung conditions, and cause coughing, wheezing and difficulty breathing.

Determine if there is Harmful Exposure

When employees are working outdoors where the air is affected by wildfire smoke, employers are required by Cal/OSHA's standards on Control of Harmful Exposure to Employees and Respiratory Protection to determine if the outdoor air is a "harmful exposure" to employees. Exposure is harmful when the pollution or contaminants in the air cause (or are likely to cause) injury, illness, disease, impairment or loss of function. Shortness of breath, difficulty breathing, frequent coughing, and severe eye and throat irritation are signs of impairment or loss of function.

Local air quality districts provide information on outdoor air that can assist employers in determining if the outside air is harmful to employees. Employers should pay special attention when the outdoor air quality for airborne particles is "unhealthy," "very unhealthy," or "hazardous." The outdoor air quality is posted at the U.S. EPA website airnow.gov.

The following factors should also be considered when determining if the outdoor air is harmful:

  • How long workers are outside
  • Level of physical exertion
  • Symptoms consistent with exposure to wildfire smoke, such as those listed above
  • Pre-existing medical conditions

Protect Workers if the Outside Air is Harmful

When exposure to wildfire smoke is considered harmful, employers are required by Cal/OSHA's Control of Harmful Exposure standard to take the following measures to protect workers:

  • Implement feasible modifications to the workplace to reduce exposure. Examples include providing enclosed structures or vehicles for employees to work in, where the air is filtered.
  • Implement practicable changes to work procedures or schedules. Examples include changing the location where employees work or reducing the amount of time they work outdoors.
  • Provide proper respiratory protection equipment, such as disposable filtering facepiece respirators (dust masks), other half facepiece respirators, or full facepiece respirators* if the previous measures are not feasible or do not prevent harmful exposures. See the following webpages and the "Resources" section below for further information on providing respirators to employees.

*To filter out fine particles, respirators must be labeled N-95, N-99, N-100, R-95, P-95, P-99, or P-100, and must be labeled as approved by the US National Institute for Occupational Safety and Health (NIOSH). Full facepiece respirators provide at least five times as much protection from fine particles as half facepiece respirators such as filtering facepiece respirators (dust masks).

If the Outside Air is Not Harmful

If an employer determines the outside air is not harmful, the employer may voluntarily provide filtering facepiece respirators (dust masks)* to employees or allow employees to bring their own. See the following webpages and the "Resources" section below for further information on providing respirators to employees.

*To filter out fine particles, respirators must be labeled N-95, N-99, N-100, R-95, P-95, P-99, or P-100, and must be labeled as approved by the US National Institute for Occupational Safety and Health (NIOSH).

Resources

November 2018