How to Fit-Test Respirators

A respirator must be fit-tested before it is used for protection against an actual airborne hazard. Fit-testing ensures an adequate seal between the user's face and the material of the respirator. The fit test method can be quantitative or qualitative. The Quantitative Fit Test (QNFT) uses an instrument that measures either leakage of an aerosol test agent or face piece pressure loss. Qualitative Fit Testing (QLFT) is performed using odor, taste or irritation response. Odor testing is done using banana oil (isoamyl acetate). Taste testing uses saccharin or Bitrextm (denatonium benzoate). Irritating smoke (stannic chloride) is used as an irritant to test a respirator's seal.

Things You'll Need

• Respirator selection
• Fit test chemical (QLFT)
• Three one-liter containers with lids
• 55-gallon drum liner
• Hook
• Hood
• Nebulizer
• Smoke tubes
• Air bulb
• Fit test instrument (QNFT)

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Instructions

• 1

  Show test subjects how to select and don a respirator that meets their work requirements. Let them select a respirator that fits them comfortably.

• 2

  Explain the fit-testing procedures and the exercises that must be performed: normal breathing, deep breathing, turning the head side to side, moving the head up and down, talking, grimacing and jogging in place or bending at the waist.

• 3

  Prepare test solutions for Qualitative Fit Testing. Test each subject to be sure they are able to detect the test chemical. Provide subjects being quantitatively fit tested with the same model respirator they selected, but fitted with a test probe.

• 4

  For banana oil testing, hang a drum liner upside down about six inches above the head of the test subject. Attach a hook to the inside of the liner. A manufactured hood with a clear face piece and ¾-inch opening is used for saccharin and Bitrex(tm) testing. No enclosures are required for irritating smoke testing.

• 5

  Have the test subject stand inside the drum or don the hood. A paper towel wetted with diluted banana oil is placed on the hook in the drum. A nebulizer filled with saccharin or Bitrex is placed in the opening of the hood. Place a smoke tube in the bulb for the irritating smoke test, which is performed in the open.

• 6

  For QLFT, expose the subject to the test chemical while performing the required exercises. Follow the instrument manufacturer's directions for QNFT.

• 7

  The subject passes the QLFT if the test chemical is not detected inside the face piece. An instrument printout will indicate if QNFT test subjects pass.