Fit Checking Your Respirator

It's important to check your respirator for the proper fit each time you put it on. Respirators can only work effectively if they fit correctly. A respirator that
does not fit appropriately may allow contaminants to enter around the
facepiece and be inhaled by the wearer.
Additional Resources:
How to Select a Respirator
Types of Respirators and Cartridges
How to Fit Test Your Respirator
Putting on (Donning) Your Respirator
Perform respirator fit checking each time
you put it on. Follow these instructions for
properly fit checking your respirator.
Fit Check for Disposable Filtering Facepiece Respirators
Fit Check for Disposable Filtering
Facepiece (Particulate or Dust/Mist/Fume) Respirators:
1. Cup both hands over the front of the mask
    (to cover the filter media) and inhale.
    Do not push on the mask.
2. Check to see if the facepiece pulls in
    toward your face.
3. If the mask is drawn in and no air leaks are
    detected around the facepiece, you have a proper
    fit. If you detect any leakage of air, try readjusting
    the nosepiece and/or the straps until you
    achieve a good fit.
Fit Check for Half Mask and Full-face Respirators
Fit Checks for Half Mask and Full-face Respirators:
Positive Pressure Fit Check:
1. Block the exhalation valve with the palm of
    your hand.
2. Gently exhale and hold for
    about 10 seconds.
3. Check to see if the facepiece
    is bulging slightly.
4. If the facepiece remains bulging and there
    are no air leaks between your face and the
    facepiece, your respirator fits properly. If
    you do detect leaks, readjust the straps
    and check again for a proper fit.
Fit Checks for Half Mask and Full-face Respirators: Fit Check for Half Mask and Full-face Respirators
Negative Pressure Fit Check:
1. Block the cartridges/filters with the palms
    of your hands.
2. Gently inhale and hold for
    about 10 seconds.
3. Check to see if the facepiece is
    collapsing slightly.
4. If the facepiece remains collapsed and
    there are no air leaks between the face and
    facepiece, you have a properly fitting respi-
    rator. If you detect leaks, readjust the straps
    and check again for a proper fit.