OSHA Assigned Protection Factors

ORIGIN: Moldex Technical Services Department


OSHA has promulgated APFs that have been incorporated into its respiratory protection standard. This completed its revision of the reserve sections of OSHA’s Respiratory Protection Standard as published in 1998. The APF for Half Mask Respirators, which includes Moldex disposable and reusable respirators, is 10. The APF for full face respirators is 50, when quantitatively fit tested.

APFs are numbers that indicate the level of workplace respiratory protection that a respirator or class of respirators is expected to provide to employees when used as part of an effective respiratory protection program. Employers must use APFs to select the appropriate type of respirator based upon the exposure limit of a contaminant and the concentration of the contaminant in the workplace. The APF multiplied by the contaminant’s exposure limit gives a Maximum Use Concentration (MUC). If the workplace level of the contaminant is expected to exceed the respirator’s MUC, the employer must choose a respirator with a higher APF.

All respirators must be properly fit tested. All respirators must be used in accordance with all local and federal regulations including OSHA 29CFR1910.134.


OSHA: www.osha.gov
Information on Moldex Respiratory Protection, including a Chemical Selection Guide that includes contaminants and their exposure limit, can be found at www.www.moldex.com.
If you should have any questions, please contact the Moldex Technical Service Department at 800-421-0668 x512/550 or email at tech@moldex.com.

WARNING: The information contained in this Tech Brief is dated and was accurate to the best of Moldex’s knowledge, on the date above. It is not meant to be comprehensive, nor is it intended to be used in place of the warning/use instructions that accompany Moldex respirators. Outside of the USA, check with all applicable and local government regulations.

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