N95 Mask Commonly Asked Questions
A: An N95 mask is a disposable filtering facepiece respirator with two straps. When worn properly (with the mask making a tight seal with the user's face), it can protect against hazardous airborne particles. N95 masks do not protect against gases, vapors and cannot be used for asbestos, and they do not provide oxygen. The "N" designation means the mask is not resistant to the effects of oil mists. For instruction on using filtering facepieces, see Using Disposable Respirators in English and Spanish.
A: When working conditions include harmful exposure to airborne contaminants such as wildfire smoke. The masks will not protect the user if the mask does not make a tight seal with the user's face due to factors such as facial hair that interferes with the seal or the mask not being put on correctly.
A: The employer must first determine whether respirator use is voluntary or required. Employers are required to provide respiratory protection if the working conditions include harmful exposures. Along with providing the respirators, the employer must have a written respiratory protection program that addresses: proper selection of respiratory equipment; employee training; medical evaluation of an employee's ability to wear a respirator; ensuring proper fit of the respirators; and proper respirator use, storage, and cleaning. The employer must also follow all other applicable requirements in section 5144.
Where it's reasonable to anticipate employee exposure to wild fire smoke, employers are required to provide employees with respirators for voluntary use in accordance with section 5144 when the current AQI for PM 2.5 is 151 or higher but does not exceed 500. Use of respirators becomes mandatory when the current AQI for PM2.5 exceeds 500. Reference section 5141.1.
When protecting employees from wildfire smoke when the current AQI is greater than 500, the employer must provide respirators with an assigned protection factor, as listed in section 5144, such that the PM2.5 levels inside the respirator correspond to an AQI less than 151. When the current AQI is greater than 535, a respirator with an assigned protection factor greater than 10 (not a disposable dust mask) is required.
A: Where respirator use is voluntary, the employer may provide respirators at the workers' request, or permit workers to use their own respirators. In this situation, employers are not required to have a written respiratory protection program or medically evaluate and fit test workers. However, the employer must ensure that the workers' use of a respirator will not create a hazard. The employer must also provide respirator users with the information contained in California Code of Regulations, Title 8, section 5144, Appendix D, and must follow all other requirements in section 5144, subsection (c)(2).
Where it's reasonable to anticipate employee exposure to wild fire smoke, employers are required to provide employees with a sufficient number of respirators for voluntary use in accordance with section 5144 when the current AQI for PM 2.5 is 151 or higher but does not exceed 500. Reference section 5141.1. The employer must also provide training to employees that contains the information of section 5141.1 Appendix B.
A: Where respirator use is voluntary, the employer may permit workers to use their own respirators or provide respirators at the workers' request. In this situation, employers are not required to have a written respiratory protection program or medically evaluate and fit test workers. However, the employer must ensure that the workers' use of a respirator will not create a hazard. The employer must also provide respirator users with the information contained in California Code of Regulations, title 8, section 5144, Appendix D, and must follow all other requirements in section 5144, subsection (c)(2).
Where it's reasonable to anticipate employee exposure to wild fire smoke, the employer can allow employees to use their own respirators when the current AQI for PM2.5 is less than 151. Reference section 5141.1.
A: N95 masks can be purchased from online retailers and from businesses such as hardware stores and industrial supply stores. N95 masks from federal, state, and local agencies are sometimes available at various locations in response to recent wildfires, such as the California Governor's Office of Emergency Services (Cal OES).
- Using Disposable Respirators
- Section 5144 Respirator Protection
- Section 5144 Appendix D Guide to Respiratory Protection at Work
- Section 5141.1 Protection from Wildfire Smoke
- Governor's Office of Emergency Services (Cal OES)
- Worker Safety and Health in Wildfire Regions
- Cal/OSHA's Respiratory Protection publication
- The U.S. EPA AirNow
- The U.S. Forest Service
- The Interagency Wildland Fire Air Quality Response Program
- The California Air Resources Board
- The local air pollution control district
- The local air quality management district
February 2021