What is a Respiratory Fit Test?

What is a Respiratory Fit Test?


by Katie Palmer        09/24/2020


Why conduct a respiratory fit test?

If any of your employees wear respirators, whether optional or mandatory, you need a Respiratory Protection Program. N95 and KN95 “masks” are not masks, but respirators.

If you mandate any employees wear a respirator, then a fit test is a required aspect of the Respiratory Protection Program. If employees wear respirators voluntarily, you don’t need to conduct the test.

For employees you mandate to wear a respirator, failure to conduct a fit test can lead to an OSHA fine. The test is legally required. Why? Because a respirator can’t protect an employee if it doesn’t fit.

Who can perform the respiratory fit test?

Anyone trained to perform a respiratory fit test can conduct it. 

Smart Training’s Compliance Advisers recommend conducting the tests in-house. This cuts costs. However, you may decide to visit an occupational health clinic due to lack of available tests. Most of the clinics offer walk-in testing. If you conduct the medical evaluations yourself, you can save $20-40 per user.

Fit test vs. User Seal Check

You must complete a fit test for each required respirator user. The fit test must be completed before the employee uses the respirator. It also must be completed annually afterward. However, due to the COVID-19 pandemic, the annual requirement has been temporarily rescinded by OSHA. But only if you complete the initial fit test.

In contrast, a user seal check is a procedure every respirator user must conduct every time they don a respirator. This check ensures the respirator seals around the employee’s face correctly. 

Conducting a Respiratory fit test

There are two types of tests: qualitative and quantitative.

Qualitative fit testing is a pass/fail test method. It uses an employee’s sense of taste, smell, or irritation to detect leakage into the respirator. This type of testing does not measure the amount of leakage. Whether an employee passes or fails the test is based on if they detect leakage of the test substance into the facepiece. If employees can smell or taste the substance, or it makes them cough, they fail.

There are four qualitative test methods accepted by OSHA:

  • Isoamyl acetate, which smells like bananas
  • Saccharin, which leaves a sweet taste 
  • Bitrex, which leaves a bitter taste 
  • Irritant smoke, which can cause coughing

Qualitative fit testing is for half-mask respirators. These only cover the user’s mouth and nose. Examples include filtering facepiece respirators, such as the N95, and elastomeric respirators. The N95 respirator is most commonly used in dental practices. 


An example of qualitative fit testing.

In contrast, quantitative testing uses a machine to measure the amount of leakage. This test does not rely upon the employee’s sense of taste, smell, or irritation. 

There are three quantitative test methods accepted by OSHA:

  • Generated aerosol
  • Ambient aerosol
  • Controlled Negative Pressure

You can use quantitative testing for any type of tight-fitting respirator.

Many workers wear prescription glasses or personal protective equipment (PPE) on the job. If an employee needs to wear extra gear on their face, they must wear them during the test. This ensures the extra PPE doesn’t interfere with the respirator’s fit.


If at any time during the fit test the subject exhibits difficulty breathing, stop the test. Refer them to a health care professional.

Saccharin and Bitrex are concentrated, bitter substances. The person administering the test may want to wear gloves.

After the test

After passing a test with a respirator, employees must use the exact same make, model, style, and size respirator on the job.

If you want your employees to wear a different respirator, you will have to conduct another fit test.

Train Employees to Conduct Tests

Smart Training’s Platinum+ Dental Solution and OSHA & HIPAA Essentials, and our Complete Medical Compliance feature a Respiratory Protection Program for your practice. The set up time is 15-20 minutes. Check out our blog to learn more about setting up your program on our learning software.

These packages also feature respiratory training modules for both employees and administrators. The training for administrators teaches them how to perform the fit test.

Request a demonstration if you have none of the above plans and still want respiratory protection.

We handle your compliance, so you don’t have to.

Smart Training
820 W Spring Creek Pkwy, Ste 400-R Plano, Tx 75023