The U.S. Department of Labor's Occupational Safety and Health Administration has issued a final rule that provides employers with two new fit testing protocols for respirators.

The new protocols are the modified ambient aerosol condensation nuclei counter quantitative fit testing protocol for full-facepiece and half-mask elastomeric respirators, and the modified ambient aerosol CNC quantitative fit testing protocol for filtering facepiece respirators.

Both protocols are variations of the original OSHA-approved ambient aerosol CNC protocol, but have fewer test exercises, shorter exercise duration, and a more streamlined sampling sequence.

These two quantitative methods add to the four existing in Appendix A of OSHA’s Respiratory Protection Standard, which contains mandatory respirator fit-testing protocols that employers must choose from to protect employees.

The rule does not require employers in general industry, shipyard employment, and construction to update or replace their current fit testing methods, and does not impose additional costs.

The rule became effective September 26, 2019.


For more information, contact CBIA's Phillip Montgomery (860.244.1982).