Fit Testing Guidance for Mandatory Use of Respirators

Using a respirator may place a physiological burden on employees that varies with the type of respirator worn, the job and workplace conditions in which the respirator is used, and the medical status of the employee.  Before an employee may be required to use any respirator, the employee must be evaluated to determine that they are medically able to wear the respirator.  The Occupational Safety and Health Administration (OSHA) requires that a medical evaluation be performed to determine an employee's ability to use a respirator, before the employee is fit tested or required to use a respirator in the workplace.

Use of a respirator requires proper fit testing, OSHA’s Fit Testing procedures are specified in Appendix A of 1910.134 - Fit Testing Procedures (Mandatory).

Fit Testing may be quantitative or qualitative. The individual performing the Fit Test procedure requires no special certification. However, the individual must be able to prepare the test solutions, calibrate the equipment and perform the tests properly, recognize invalid tests, and ensure that test equipment is in proper working order. The ability to calculate fit factors is also a requirement for the individual administering a Quantitative Fit Test.

Specific Fit Testing procedures will vary depending on which respirator is selected, whether a quantitative or qualitative protocol is used, and other factors. The following provides general guidance on Qualitative Fit Testing procedures for the use of a NIOSH-certified N95 filtering facepiece respirators. 

Directions for Proper Donning

Proper donning of an N95 filtering facepiece respirator may feel a little awkward at first, but it will become easier with repeated applications. The following instructions should be followed when donning fold flat respirators (see manufacturer’s instructions for other respirator models):

1. Separate the edges of the respirator to fully open it.
2. Slightly bend the metal nosepiece to form a gentle curve.
3. Hold the respirator upside down to expose the two headbands.
4. Using your index fingers and thumbs, separate the two headbands.
5. While holding the headbands with your index fingers and thumbs, cup the respirator under your chin.
6. Pull the headbands up over your head.
7. Release the lower headband from your thumbs and position it at the base of your neck.
8. Position the remaining headband at or near the crown of your head.
9. Conform the nosepiece across the bridge of your nose by firmly pressing down with your fingers.
10. Continue to adjust the respirator and secure the edges until you feel you have achieved a good facial fit. Now, perform a Fit Check.

Directions for Performing a User Seal Check

To ensure N95 filtering facepiece respirators are providing the intended level of protection, a “User Seal Check” MUST be performed each and every time they are worn.

To Seal Check a respirator, the wearer should forcefully inhale and exhale several times. The respirator should collapse slightly upon inhaling and expand upon exhaling. The wearer should not feel any air leaking between his/her face and the respirator. This is the sign of a good facial fit and a successful Seal Check.

If the respirator does not collapse and expand OR if air is leaking out between the wearer’s face and the respirator, then this is NOT a good facial fit. The wearer should adjust the respirator until the leakage is corrected and he/she is able to successfully perform a User Seal Check with the respirator.

Note: A User Seal Check is NOT a substitute for Fit Testing. A User Seal Check is a simple procedure intended to help the wearer verify that he/she has properly donned the respirator. Fit Testing is designed to determine that an appropriate size respirator and an adequate fit has been achieved for each wearer.

Tips for Achieving a Good Fit

If the wearer is having a problem successfully performing a User Seal Check with the respirator, he/she should try the following tips:

1. Use a mirror while adjusting the respirator.
2. Make sure the headbands are positioned properly. It is especially important that the top headband is on the crown of your head, as it is designed to hold the bottom of the respirator snug against your chin.
3. Note:It is important to stress to the wearer that:
   • The respirator must be User Seal Checked each and every time it is donned, and
   • He/she should not proceed with activities until a successful Fit Check has been completed.

Qualitative Fit Testing Protocol

This guidance provides instruction on Qualitative Fit Testing using the Bitrex^TM method. The Qualitative Fit Testing protocol consists of two parts: a Threshold Check and a Fit Test. The Threshold Check determines the subject’s ability to taste a weak solution of the challenge agent.

1. Pour the contents of Threshold Check Solution into the Threshold Check nebulizer. Prepare the Fit Test nebulizer with the Fit Test Solution in the same manner.
2. Assemble the hood by pressing the VELCRO® strips together and fitting the bouffant cap over the top, securing the seam of the cap under the tabs on the hood.
3. The Fit Test protocol should be explained to the test subject prior to testing. The test subject should not eat, chew gum, or drink anything but water for at least 15 minutes prior to the test.
4. Record the name of the test subject, type of respirator (N95), brand and size of respirator, and date of the test.

Threshold Check Procedure

1. Have the test subject put on the hood without a respirator.
2. Instruct the subject to breathe normally with his/her mouth open.
3. Instruct the subject to immediately report when the challenge agent is tasted.
4. Insert the nozzle of the Threshold Check nebulizer into the hole at the front of the hood being sure to point the nebulizer away from the nose and mouth area. Squeeze the bulb firmly ten times. (If the person reports a taste during this process, stop squeezing. Record “10” as the number of squeezes required, regardless of when the person reported the taste.)
5. If the subject has not tasted the solution, administer another 10 squeezes. (If the person reports a taste during this process, stop squeezing. Record “20” as the number of squeezes required, regardless of when the person reported the taste.)
6. If the subject has not tasted the solution, administer another 10 squeezes and ask again if they have tasted the solution. (If the person reports a taste during this process, stop squeezing. Record “30” as the number of squeezes required, regardless of when the person reported the taste.)
7. If no taste has been detected, and if saccharin is being used, then the subject should be tested with the alternative BITREX® solution using these same procedures. If the subject is unable to taste either saccharin or BITREX®, then the subject cannot be tested using this protocol. Instead, quantitative Fit Testing is suggested.
8. Remove the hood and allow the subject to rinse his/her mouth with water and wipe his/her face. The subject should not proceed to the Fit Test until the taste of the challenge agent has been allowed to clear, which usually takes several minutes.

Fit Test Procedure

1. Have the subject put on the respirator and perform a User Seal Check. The subject should be allowed to wear the respirator for at least five minutes prior to beginning the fit test, adjusting it as needed.
2. Place the hood on the subject, making sure that there is sufficient room for the subject to move his/her head from side to side and up and down without the mask touching the sides of the hood.
3. Instruct the subject to breathe through his/her open mouth for the duration of the test and to report if the taste of the solution is detected at any time during the test.
4. Insert the nozzle of the Fit Test nebulizer into the hole at the front of the hood, pointing it away from the nose and mouth, and spray 10, 20, or 30 squeezes into the hood, depending on which number was recorded from the Threshold Check.
5. Maintain the aerosol concentration in the hood throughout the test by squeezing one half the initial number of squeezes every 30 seconds into the hood.
6. Instruct the subject to perform the series of exercises below for 60 seconds each:
   • Normal Breathing
   • Deep Breathing
   • Turning head from side to side (pausing for a breath when head is to side)
   • Moving head up and down slowly (pausing for a breath while head is up)
   • Talking (reading the enclosed “Rainbow Passage,” reciting the alphabet, etc.)
   • Grimace (smiling or frowning) for 15 seconds
   • Jogging in Place
   • Normal Breathing
7. If the exercises are completed without the subject tasting the aerosolized solution, then an acceptable fit has been demonstrated and the subject has passed the test.
8. If the subject reported tasting the aerosolized solution during the test, then the subject has failed to achieve an acceptable fit. The test subject should be allowed to re-test with the same model respirator or with another model respirator of his/her choice. Wait at least 15 minutes before re-testing and begin by repeating the Threshold Check.

Cleaning-Up

1. Rinse the nebulizers with warm water to prevent clogging.
2. Wipe out the inside of the hood with a damp cloth or paper towel to remove any solution residue. A disinfectant, such as isopropyl alcohol, may be used for cleaning to reduce potential contamination.

This document provides general guidance only for employees covered by Title 5, United States Code, and does not, and is not intended to create or violate any legal rights.