How to conduct user seal checks on 3M™ Disposable and Reusable Respirators

March 20, 2018

Imagine what it would feel like to wear a baseball hat that is too big. You’d have a hard time keeping it in position and it would constantly  fall down, obstructing your vision. While a hat that doesn’t fit properly is an inconvenience, a respirator that doesn’t fit properly is much more than that. A poorly fitting respirator will not create a proper seal and can put your health at risk.

That’s why per CSA Respiratory Standard Z94.4, all workers required to wear tight-fitting respirators must be fit tested prior to initial use, when there are changes to the user’s physical condition, a change in respirator, difficulty completing a user seal check, a change in other PPE that may affect the respirator and at least every two years. In addition to this, workers need to perform a seal check each time they don their respirator before entering a contaminated area to ensure adequate protection.

Respirators can help reduce exposures to on-the-job hazards such as particles, gases and vapours. If the respirator doesn’t fit properly, it may not form a tight seal to the wearer’s face, allowing contaminants to leak around the edges and be inhaled instead of passing through the filter.

Since a user seal check must be performed every time a respirator is worn, it’s important to ensure it’s done correctly each time. Below you’ll find how to perform both positive and negative pressure user seal checks on 3M™ Disposable and Reusable Respirators.

How to conduct a user seal check on a respirator with an elastomeric facepiece

Positive pressure user seal check

1. Cover the opening in the exhalation valve cover with your hand and exhale gently. If the facepiece bulges slightly and no air leaks are detected between your face and facepiece, a proper seal has been obtained.

2. If face seal air leakage is detected, reposition the respirator on your face and/or readjust tension of the elastic straps to eliminate leakage.

Negative pressure user seal check

1. Place the palms of your hands to cover the face of the cartridge or filter.

2. Inhale gently. If you feel the facepiece collapse slightly and pull closer to your face with no leaks between your face and facepiece, a proper seal has been obtained.

3. If face seal air leakage is detected, reposition the respirator on your face and/or readjust the tension of the straps to eliminate air leakage.

How to conduct a user seal check on a non-valved disposable respirator

To check the respirator-to-face seal, place both hands completely over the respirator and exhale sharply. Be careful not to disturb the position of the respirator. If air leaks around your nose, readjust the nosepiece. If air leaks at the respirator edges, work the straps back along the sides of your head. If you CANNOT achieve a proper seal, DO NOT enter the contaminated area. See your supervisor.

How to conduct a user seal check on a valved disposable respirator

To check the respirator-to-face seal, place both hands completely over the respirator and inhale sharply. Be careful not to disturb the position of the respirator. A negative pressure should be felt inside the respirator. If air leaks around your nose, readjust the nosepiece as described in step 3. If air leaks at the respirator edges, work the straps back along the sides of your head. If you CANNOT achieve a proper seal, DO NOT enter the contaminated area. See your supervisor.

If you need more information about your respirator, fit testing or how to perform a user seal check, please contact the 3M Canada Safety Centre at 1-800-267-4414.

Previous Article
Features of 3M™ Filtering Facepiece Disposable Respirators
Features of 3M™ Filtering Facepiece Disposable Respirators

With Advanced Electrostatic Media, 3M™ Disposable Respirators allow you to breathe easier.

Next Article
Can I have facial hair under my respirator?
Can I have facial hair under my respirator?

Any welders wondering if they can have facial hair under their respirator? The short answer is that it depe...