Sensitivity and Fit Tests

Sensitivity Test

This test is done to assure that you can detect the taste of the test solution at very low levels.  The Sensitivity Test Solution is a very diluted version of the fit tests solution.  You should not eat, drink or chew gum for 15 minutes before the test.

  1. Put on the hood without a respirator.
  2. Position the hood forward so that there is about six inches between face and hood window.
  3. Breathe through the mouth.
  4. Using the Nebulizer #1 with the Sensitivity Test Solution, inject the aerosol into the hood through the hole in the hood window.   Inject ten squeezes of the bulb, fully collapsing and allowing the bulb to expand fully on each squeeze.
  5. Determine whether the sweet taste of the solution is detectable.  If tasted, note the number of squeezes and proceed to the fit test.
  6. If not tasted, inject an additional ten squeezes of the aerosol into the hood.  Repeat with ten more squeezes if necessary.  Note the number of squeezes required to produce a taste response.
  7. If 30 squeezes are inadequate, the test should be ended and another type of fit test must be used because the subject cannot detect the test agent.
  8. Remove the test hood and allow a few minutes to clear the taste from the mouth.

Fit Test

  1. Put on and fit check the respirator per the instructions provided with the respirator.
  2. Put on and position the test hood as before and breath through the mouth.
  3. Using Nebulizer #2 with the Fit Test Solution, inject the fit test aerosol using the same number of sqeezes noted in the sensitivity test.
  4. To maintain an adequate concentration of aerosol during this test, one-half the number of squeezes used in step 3 is injected every 30 seconds.
  5. After the initial aerosol is injected, perform the following test exercises for 60 seconds each.*
    • Normal breathing.
    • Deep breathing - breaths should be deep and regular.
    • Turning head from side to side - movements should be completed with one turn every second.
    • Nodding head up and down - movements should be completed one per second.
    • Talking - ask the subject to count backwards from 100.
    • If the entire test is completed without the subject detecting the sweet taste of the aerosol, the test is successful and the respirator fit is deemed adequate.