ASTM F3407-20 and ASTM F3407-21 Respirator Fit Test Standard

The Importance of Performance Validation Testing  – Jacob Persky, MPH, CIH; Wendi Egan; Roy McKay, Ph.D.

ASTM’s personal protective clothing and equipment committee developed the ASTM F3407-20 and F3407-21 Standard Test Method for Respirator Fit Capability for Negative-Pressure Half-Facepiece Particulate Respirators (RFC Standard).

The ASTM Standards F3407-20 and F3407-21 provides increased assurance to respirator purchasers and users that respirators that meet the requirement of this standard can be expected to effectively fit persons with various length and widths of faces, such as long and narrow or short and wide, when fit tested as part of a complete respiratory protection program in accordance with 29 CFR 1910.134.

Subjects enter a chamber containing a sodium chloride (salt) aerosol and perform eight exercises (normal breathing, deep breathing, turning head side to side, moving head up and down, talking, grimacing, bending over, and normal breathing).

The equipment measures the concentration of airborne salt particles present both inside the mask and outside the mask in the chamber. To pass, a subject must achieve a good quality fit that results in the concentration of salt particles inside the mask being at least 100 times lower than the concentration of salt particles outside the mask (fit-factor of 100 or higher).

At least 13 of 25 test subjects must obtain an overall fit factor of 100 or greater for the model to pass the Respirator Fit Capability test.

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