Industrial Mask Fit Testing

A fit test is a test protocol conducted to verify that a respirator is both comfortable and provides the wearer with the expected protection. Fit testing uses a test agent, either qualitatively detected by the wearer’s sense of taste, smell, or involuntary cough (irritant smoke) or quantitatively measured by an instrument, to verify the respirator’s fit.

For more information, view the OSHA Respirator Fit Testing video and NIOSH fact sheet, Filtering out Confusion: Frequently Asked Questions about Respiratory Protection, Fit Testing.

Tight-fitting respirators used within a workplace respiratory protection program are required to be fit tested prior to use. Tight-fitting respirators include filtering facepiece respirators, elastomeric half and full facepiece respirators, tight-fitting powered-air purifying respirators, self-contained breathing apparatus, etc..

For more information, see the NIOSH fact sheet, Filtering out Confusion: Frequently Asked Questions about Respiratory Protection, Fit Testing.

You should be fit tested at least annually to ensure your respirator continues to fit you properly. Because each brand, model, and size of respirators will fit slightly different, you should be fit tested every time you wear a new model, manufacturer type/brand, or size. Also, if your weight changes or facial/dental alterations occur, a fit test should be done again to ensure your respirator remains effective.

For more information, see the NIOSH infographic, Why are annual fit tests required?

No. A fit test only qualifies you to use the specific brand/make/model/size of respirator for which you successfully passed a fit test. Respirator sizing varies across different manufacturer brands and models. Therefore, you should only wear the specific brand, model, and size respirator that you wore during a successful fit test.

A qualitative fit test (QLFT) relies on the respirator wearer’s senses to determine if there is a gap in the seal of the respirator to the wearer’s face. The OSHA-accepted fit test protocols provide complete instructions for conducting QLFTs with the accepted test agents. Note: NIOSH does not endorse or recommend the use of the irritant smoke fit test. To learn more about preparing solutions for qualitative fit testing, view the NIOSH webpage.

For more information, see the NIOSH fact sheet, Filtering out Confusion: Frequently Asked Questions about Respiratory Protection, Fit Testing.

A quantitative fit test uses a fit testing instrument(s) to provide quantitative, or numerical, measurements of the amount of face seal leakage present when a user wears a respirator. Quantitative fit testing requires a hole punched in the respirator to perform the test. Therefore, the fit tester must dispose of the respirator after the test.

For more information, see the NIOSH fact sheet, Filtering out Confusion: Frequently Asked Questions about Respiratory Protection, Fit Testing.

A user seal check is a quick procedure you conduct every time you wear a respirator to make sure you donned the respirator properly. The user seal check can be either a positive pressure or negative pressure check. The appropriate type of user seal check depends on the respirator.

• Positive pressure user seal check—The person wearing the respirator exhales gently while blocking the paths for air to exit the respirator to make sure there aren’t any leaks. A successful check is when slight pressure builds up in the respirator without any leakage.
• Negative pressure user seal check— The person wearing the respirator quickly inhales while blocking the paths for air to enter the facepiece. A successful check is when the facepiece collapses slightly under the negative pressure.

According to the OSHA respiratory protection standard, appendix B-1, once  you successfully pass a fit test, you should complete a user seal check every time you put on the respirator to ensure you achieve an adequate seal.

According to the OSHA respiratory protection standard, appendix B-1, once  you successfully pass a fit test, you should complete a user seal check every time you put on the respirator to ensure you achieve an adequate seal.

Follow the manufacturer’s instructions to perform a user seal check on the specific model you are wearing. This information is available on the box or individual respirator packaging. There are positive and negative pressure user seal checks, and not every respirator can be checked using both.

Please refer to our fact sheet, Filtering out Confusion: Frequently Asked Questions about Respiratory Protection, User Seal Check, for additional information.

A medical evaluation determines your ability to wear a respirator. You must complete a medical evaluation before you are fit tested and before using a respirator in a workplace.

Yes. The Occupational Safety and Health Administration (OSHA) standard (29 CFR 1910.134) requires a medical evaluation as an element of the written respiratory protection program.

How often do I need to get a medical evaluation

A medical evaluation is required once, prior to initial fit testing and use in your workplace. However, you may need an additional medical evaluation if you, your supervisor, or your respiratory program administrator recognize signs or symptoms that may affect your ability to use the assigned respirator. Additionally, a licensed healthcare professional may determine that you have a condition that causes you to need another medical evaluation.

View the OSHA Medical Evaluations for Workers Who Use Respirators video