Appendix F: Bitter and Sweet Aerosol Fit Test Protocol

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Part 1: Health and Safety Cautions
  • No hazards associated with conducting these fit test protocols have been identified by CSA (Canadian Standards Association).
  • See Appendix E for the MSDS for Denatonium Benzoate. Note that Denatonium Benzoate (Bitrix) and Sodium Saccharin are not WHMIS controlled and are not considered hazardous materials.
Part 2: Preparation of the Test Solutions
  • Either Denatonium Benzoate (Bitter) or Saccharin (Sweet) test solutions may be used for fit testing.
  • Pour a small amount (approximately one teaspoon) of the Sensitivity Test Solution into the nebulizer labeled “#1 Sensitivity Test Solution.”
  • Pour the same amount of Fit Test Solution into the second nebulizer labeled “#2 Fit Test Solution.”
  • Immediately recap the bottles.
  • Remove both white plugs on the nebulizer during use.
Part 3: Sensitivity Screen Test

The test subject should not eat, drink (except water), or chew gum for 15 minutes before the test.

  • Have the respirator user put on the hood and collar assembly without a respirator.
  • Position the hood assembly forward so that there is about six inches between the user’s face and the hood window.
  • Instruct the user to breathe through his/her mouth with tongue extended.
  • Using 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 expanding the bulb on each squeeze. Hold the nebulizer in an upright position.
  • The respirator user will acknowledge when they detect the sensitivity solution. If tasted, note the taste threshold as 10 squeezes on Form B: Respirator Fit Testing and proceed to the Fit Test.
  • If not tasted, inject an additional ten squeezes. Repeat with ten more squeezes if necessary. Note on Form B whether 20 or 30 squeezes produced a taste response.
    • Note: If the respirator user is not able to detect the solution after 30 squeezes, the alternate test solution must be used.
  • Remove the test hood, and give the respirator user a few minutes to clear the taste from his/her mouth. It may be helpful to have the subject rinse his/her mouth with water.
Part 4: Fit Test
  • The respirator user will don their selected respirator and perform a user seal check per the instructions provided on the respirator package (See Appendix G).
  • Have subject wear any applicable safety equipment that may be worn during actual respirator use that could interfere with respirator fit.
  • Have the test subject put on and position the test hood as before, and breathe through his/her mouth with tongue extended.
  • Using Nebulizer #2 with Fit Test Solution, inject the fit test aerosol using the same number of squeezes as required in the Sensitivity Test (10, 20, or 30). A minimum of ten squeezes is required. Hold the nebulizer in an upright position.
  • To maintain an adequate concentration of aerosol during this test, inject one-half the number of squeezes (5, 10, or 15) every 30 seconds for the duration of the fit test procedure.
  • While the fit tester is challenging the respirator seal with the test solution, the test subject will perform the following fit test exercises (each exercise is to be done for 30 seconds):
    • Normal breathing
    • Deep breathing
    • Turning head side-to-side within a comfortable range of motion. Inhale and exhale when head is at either side and avoid bumping shoulder with the respirator.
    • Nodding head up and down within a comfortable range of motion. Inhale and exhale when head is at the top and bottom and avoid bumping the chest with the respirator.
    • Talking aloud. May recite the Rainbow Passage:
      • “When the sunlight strikes raindrops in the air, they act like a prism and form a rainbow. The rainbow is a division of white light into many beautiful colours. These take the shape of a long round arch, with its path high above, and its two ends apparently beyond the horizon. There is, according to legend, a boiling pot of gold at one end. People look, but no one ever finds it. When a man looks for something beyond reach, his friends say he is looking for the pot of gold at the end of the rainbow”.
  • The test is terminated at any time the taste of the aerosol is detected by the test subject because this indicates an inadequate fit.
  • If the reason for the leak can be identified and the respirator readjusted, the fit test may be repeated.
  • If the repeated fit test is unsuccessful, another size or model of respirator will need to be selected and the fit test repeated.
  • If the test subject does not report tasting the test solution, the fit test has passed.
  • When using the saccharin solution, periodically check the nebulizer to make sure that it is not clogged. If clogging is found, clean the nebulizer and retest.
Part 5: Cleaning
  • At the end of each fit-testing session or at least every four hours, discard the unused solutions from the nebulizers.
  • DO NOT pour unused solutions back into bottles. Rinse the nebulizers with warm water to prevent clogging and shake dry. Wipe out the inside of the hood with a damp cloth or paper towel to remove any deposited test solution.
  • Between test subjects, the inside of the hood may be cleaned with a sanitizing wipe (Benzalkonium Chloride 0.4%, or Hydrogen Peroxide 0.5%)