Filtering Facepiece Respirators (FFR), commonly known as N95s*, are NIOSH-approved disposable air-purifying respirators used for airborne particulates. Employers may provide FFRs for voluntary use by employees or permit employees to use their own FFR, if the employer determines that such respirator use will not in itself create a hazard. Voluntary use of FFRs is only allowed if the employee is NOT exposed to an airborne hazard at or above the permissible exposure limit (PEL). If an employer is not certain the exposure is not under the PEL they must conduct air monitoring to determine if there is a respiratory hazard. If employees are exposed at or above the PEL employers must control the hazard using the following controls in the order listed:

• Engineering control measures, such as enclosing or isolating the process, or using dilution or local exhaust ventilation must be applied first if feasible.
• Administrative controls, such as limiting exposure by adjustment of the work schedule or using safe work practices, such as wetting dusty materials or, prohibiting use of compressed air to clean off surfaces if engineering controls are not sufficient.
• Using appropriate respirators as a last resort:
  • When the controls listed above are not feasible.
  • While the controls are being instituted.
  • When the controls are not sufficient to reduce respiratory hazards to a level below established exposure limits.
  • During foreseeable emergencies.

Voluntary use of FFRs is allowed when all the following conditions have been met:

• An employee requests to use an FFR even though it is not required.
• Cal/OSHA does not require a respirator.
• A respirator is not necessary to protect the health of the employee.
• The FFR will not in itself create a hazard.

When it comes to voluntary use of FFRs:

• A written respiratory protection program is not required.
• Employers must still provide employees with the information in California Code of Regulations, Title 8, § 5144D to Section 5144: (Mandatory) Information for Employees Using Respirators When Not Required Under the Standard.
• Employees must understand the limitations of and how to use and maintain FFRs.

NOTE: Voluntary use of any other type of respirator (e.g., half-face, SCBA) requires a modified Respiratory Protection Plan and medical evaluation and the information in this article is not applicable.

Wildfire smoke.

• Where the Air Quality Index (AQI) for PM2.5 is equal to or greater than 151, but does not exceed 500, the employer must provide respirators to employees for voluntary use.
• Employers shall use California Code of Regulations, Title 8, Appendix B to Section 5141.1. Protection from Wildfire Smoke Information to Be Provided to Employees (Mandatory) in lieu of Appendix D to section 5144 for training regarding voluntary use of respirators.
• Wildfire smoke tends to clog FFRs, and they must be replaced as needed to prevent difficulty breathing or breakthrough.
• Where the AQI for PM2.5 exceeds 500, respirator use, a full Respiratory Protection Plan, medical evaluation, and fit testing is required. 

Resources

• Respiratory Protection in the Workplace – A Guide for Employers
• Voluntary Use of Filtering Facepiece Respirators Training Video
• General Industry Safety Orders, Article 107. Dusts, Fumes, Mists, Vapors and Gases

*In addition to N95s there are P95s, R95s, N100s and P100s.