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Respiratory Fit Testing



You must be fit tested before you use a respirator in the workplace, and you must be retested at least every 12 months to make sure that the respirator you use still fits you. You must be fit tested with the specific make, model, style, and size of respirator that you will be using.

Not everyone can get a good fit with one specific respirator. If the respirator fails the fit test, then another make, model, style, or size must be tried until one is found that fits you properly. Therefore, your employer needs to provide you with a reasonable selection of sizes and models to choose from. When you’ve completed the fit testing process, it’s very important that you know which make, model, style, and size respirator fits your face properly, and when and where you’ll need to wear it for protection.

Also, the fit of your respirator must be retested whenever you have a change in your physical condition that could affect the fit of your respirator. Such changes could include:

  • Large weight gain or loss;
  • Major dental work (such as new dentures);
  • Facial surgery that may have changed the shape of your face; or
  • Significant scarring in the area of the seal.
  • Any of these changes could affect the ability of your respirator to properly seal to your face, which could allow contaminated air to leak into your respirator facepiece.

If you find that the fit of your respirator becomes unacceptable, you must be allowed to select a different type of respirator and be retested. The selection may include a new make, model, style, or size of respirator.

Facial hair, like a beard or mustache, can affect your respirator’s ability to protect you. Anything that comes between your face and the respirator’s seal or gets into the respirator’s valves can allow contaminated air to leak into the respirator facepiece and you will not be protected. For example, if you have long hair, make sure it doesn’t get between the respirator seal and your face because this can allow contaminated air to leak into the respirator.

Fit testing can be done by your employer or an outside party, including a union, an apprenticeship program, a contractor’s association, or a past employer. Your current employer is permitted to accept fit testing you have received from an outside party (such as a former employer) within the last 12 months, as long as you use the same respirator make, model, style, and size at your new worksite. This is known as “fit testing portability.”

While recent fit testing can follow you from job to job, it is still your current employer’s responsibility to ensure that the fit testing and record keeping requirements of Canadian Standards Association ( CSA) respiratory protection standard have been met before you use a respirator for protection against hazardous exposures at work.

Sometimes workers own their own respirators and bring them to a job where respiratory protection is required. If your employer allows you to use your own personal respirator for protection, then your employer still has to comply with all of the requirements of the CSA standard. For example, your employer must still ensure that:

  • Your respirator is appropriate for the hazards you face;
  • Your respirator is properly cleaned, maintained, and stored; and
  • The proper schedule for replacing cartridges and filters is followed.

Keep in mind, however, that while your employer may allow you to use your own respirator, your employer cannot require you to use your own respirator.

Remember, if you don’t know if a respirator is needed for the task you will be doing, or if you are unsure about how to properly use a respirator or which filter or cartridge to use, talk to your supervisor before entering the hazardous area. Please refer to WorkSafe BC for the complete Occupational Health and Safety Guideline (Part 8) on Personal Protective Clothing and Equipment.


A qualitative fit test is a pass/fail test that relies on the employee’s response to a test agent. The CSA protocols include saccharin, isoamyl acetate (banana oil), Bitrex and irritant smoke.

For a saccharin or Bitrex test, an fit tester challenges a subject wearing a respirator with a test aerosol. The subject dons the respirator and a fit test hood. The test aerosol (saccharin or Bitrex) is sprayed inside the hood while the subject performs prescribed exercises. If the subject can taste the test agent, the respirator fails the test and another respirator must be tested. Prior to conducting the test, the administrator must determine if the subject can detect the test agent. If the subject can’t detect the test agent, another one that can be detected must be used. The fit test procedure requires about 15 to 20 minutes.

A quantitative fit test measures the adequacy of a respirator’s fit by numerically measuring the amount of leakage into the respirator. The CSA protocols include use of a PortaCount, CNC or CNP test.

The PortaCount works by measuring the concentration of microscopic dust particles in the ambient air and then measuring the concentration of those dust particles that leak into the respirator. The ratio of these two concentrations is called the fit factor. The filters stop essentially all the particles so anything that gets into the mask must have come through the face seal. A quantitative fit test is not affected by the person’s sense of smell, taste or sensitivity to irritant chemicals.


From the SCBAs and military-quality gas masks used by fire service and law enforcement to N95 filtering facepiece (disposable) respirators donned by healthcare workers and the variety of respirators used by industrial organization, the goal remains constant – protect individuals from known and unknown respiratory hazards. But the highest protection level can’t be achieved if the respirator isn’t donned properly. That’s where TSI PortaCount® Respirator Fit Testers come in.


Have peace of mind knowing that you can trust your fit test results. Passing a quantitative fit test proves that the facepiece is sized correctly and the person knows how to put it on correctly. With our TSI PortaCount Respirator Fit Tester offer:

  • Faster fit testing, real-time feedback
  • Enhanced training with real time fit factor
  • Objective fit testing, eliminating the guesswork
  • Easy-to-use touch screen interface

The TSI PortaCount Respirator Fit Tester is designed to fit test all types of respirators and masks, including an N95 respirator. The PortaCount Pro+ Respirator Fit Tester is the only instrument with built-in N95 technology to perform a quantitative fit test on an N95 respirator. The PortaCount Respirator Fit Testers are CSA-compliant for all respirators.

  • Disposable filtering-facepiece fit testing (series 100, 99, 95, P1, P2)
  • Half-mask fit testing
  • Full-face fit testing
  • Gas mask fit testing
  • PAPR fit testing
  • SCBA fit testing

Qualitative fit testing is a pass/fail test method that uses your sense of taste or smell, or your reaction to an irritant in order to detect leakage into the respirator facepiece. Qualitative fit testing does not measure the actual amount of leakage. Whether the respirator passes or fails the test is based simply on you detecting leakage of the test substance into your face piece. There are four qualitative fit test methods accepted by CSA:

  • Isoamyl acetate, which smells like bananas;
  • Saccharin, which leaves a sweet taste in your mouth;
  • Bitrex, which leaves a bitter taste in your mouth; and
  • Irritant smoke, which can cause coughing.

Qualitative fit testing is normally used for half-mask respirators – those that just cover your mouth and nose. Half-mask respirators can be filtering facepiece respirators – often called “N95s” – as well as elastomeric respirators.

Many workers need to wear prescription glasses or personal protective equipment, such as safety goggles or earmuffs, while performing a job. If you fall into this category, then you must wear these items during the fit test to be sure they don’t interfere with the respirator’s fit.