A tight fitting respirator cannot provide its intended protection without a proper face seal. To meet OSHA respirator fit test requirements, employers must complete formal testing before initial use, repeat it at least annually, and test again when a change could affect the fit.
What is a Respirator Fit Test?
A respirator fit test checks how well a tight fitting respirator seals against an employee’s face. Fit testing is required for tight fitting respirators such as:
- Filtering facepiece respirators, including N95s
- Reusable half mask respirators
- Full facepiece respirators
- Tight fitting powered air purifying respirators
- Tight fitting atmosphere supplying respirators
A fit test isn’t the same as a user seal check. The fit test is a formal procedure completed before the employee uses the respirator at work and repeated when required. A user seal check is done by the employee every time the respirator is put on. Passing the annual fit test does not replace this daily check.
When and How Often Does OSHA Require Fit Testing?
Under OSHA’s Respiratory Protection Standard, 29 CFR 1910.134 an employee must be fit tested before first using a required tight fitting respirator. A medical evaluation must come first, then the employee can move forward with the fit test.
OSHA respirator fit test requirements call for another test:
- At least once every 12 months
- When the employee changes to a different respirator facepiece
- When the employee says the respirator no longer fits properly
- When a supervisor, program administrator, medical provider, or other qualified person notices a change that could affect the fit
Major weight gain or loss, dental work, facial surgery, and scarring near the seal are all reasons an employee may need to be tested again before the annual date.
The fit test is only valid for the exact respirator tested. If an employee passes a test in one N95 model and later receives another model, another fit test is required (even if both respirators are marked as the same size.)
Qualitative vs. Quantitative Fit Tests
OSHA allows qualitative and quantitative fit testing, the right method depends on the respirator and how much protection is required for the job.
Qualitative Fit Testing
A qualitative fit test is a pass/fail test. It relies on the employee detecting a test agent that has leaked into the respirator. Depending on the procedure, the employee may notice a taste, smell, or irritation.
OSHA accepted qualitative test agents include:
- Saccharin, which produces a sweet taste
- Bitrex, which produces a bitter taste
- Isoamyl acetate, which has a banana like odor
- Irritant smoke, which causes an involuntary response
Qualitative testing may only be used for negative pressure air purifying respirators that must achieve a fit factor of 100 or less. This generally includes N95s and many reusable half mask respirators.
Quantitative Fit Testing
A quantitative fit test uses an instrument to measure how much air leaks into the respirator. It doesn’t rely on the employee’s taste or sense of smell. The equipment provides a numerical fit factor at the end of the test.
OSHA requires a minimum fit factor of:
- 100 for half mask respirators
- 500 for full facepiece respirators
Quantitative testing can be used for any tight fitting respirator. It is required when the respirator must provide more protection than a qualitative test can verify. Employers must use an accepted procedure listed in Appendix A of OSHA’s Respiratory Protection Standard.
| Test Type | How It Works | Result | Common Use |
| Qualitative | Employee detects a test agent | Pass or fail | N95s and many half mask respirators |
| Quantitative | Instrument measures facepiece leakage | Numerical fit factor | Half mask and full facepiece respirators |
During either test, the employee goes through several exercises. These may include normal breathing, deep breathing, turning the head, moving the head up and down, speaking, and bending over. The test checks how the seal holds while the employee is moving, not only while standing still.
OSHA N95 Fit Test Requirements
When an employer requires an employee to wear an N95 for protection from a workplace hazard, OSHA requires a medical evaluation, fit testing, safety training, and the other parts of a respiratory protection program.
The employee must be tested with the exact N95 that will be used on the job. A qualitative or quantitative test may be used.
The rules are different when an employee voluntarily wears an N95 in an area where respiratory protection is not required. If the employer determines that voluntary use will not create a hazard, the employer must provide the information found in Appendix D of the OSHA standard. The full fit testing requirement does not generally apply to voluntary use of filtering facepiece respirators.
An N95 only filters particles. It does not protect against gases, vapors, or an oxygen deficient atmosphere. The respirator has to match the actual hazard found in the work area.
Facial Hair and Other Fit Test Problems
OSHA does not allow an employee to wear a tight fitting respirator if facial hair comes between the sealing surface and the face or interferes with valve function. Beards, heavy stubble, and some mustache styles can prevent a proper seal.
Other items that may interfere with the fit include:
- Eyeglass temples passing through the sealing area
- Head coverings caught under the facepiece
- Straps placed in the wrong position
- Jewelry near the seal
- Facial changes since the previous test
- A different respirator than the one used during testing
Employers need to provide enough respirator models and sizes for employees to find one that fits correctly. If an employee cannot get a safe seal with a tight fitting facepiece, another type of respirator may need to be considered based on the hazard.
What Fit Test Records Must Employers Keep?
OSHA requires employers to document every qualitative and quantitative fit test. Each record must include:
- The employee’s name or identification
- The type of fit test performed
- The respirator’s make, model, style, and size
- The test date
- The pass or fail result for a qualitative test
- The fit factor and test record for a quantitative test
The employer must keep the employee’s most recent fit test record until another fit test is completed.
The records also need to match the respirators employees are actually wearing. If an employee is issued a different model or size, the old test does not apply to that respirator and a new test will be needed.
Respiratory Protection Support from Safety By Design
While fit testing is one part of an OSHA compliant respiratory protection program, employers also need to evaluate respiratory hazards, select the correct equipment, complete medical evaluations, train employees, and check how respirators are being used and maintained.
Safety By Design can help your company evaluate workplace safety practices, develop written programs, train employees, and address all OSHA compliance concerns.
Contact Safety By Design to discuss respiratory protection requirements for your workplace.
