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When you must wear a respirator to protect
yourself against airborne contaminants in
your workplace, it is very important to
follow proper procedures for putting it on
and taking it off. The process of putting on
and taking off your respirator is also referred
to as “donning and doffing.” Respirator
manufacturers supply instructions on how to
properly don and doff (put on and take off)
each respirator they produce.
The manufacturer also supplies instructions
on how to properly conduct a user seal
check. A “user seal check” is a way to
verify that the respirator has been properly
positioned on your face to assure a proper seal.
Sometimes, workers confuse the term “user
seal check” with the term “fit test,” which is
different. A user seal check is not a
substitute for a fit test, which is a more
involved process that uses a test agent or
instrument to verify the respirator’s fit. A fit
test must be performed before you wear a
respirator for the first time and at least
annually thereafter. A user seal check must
be performed each time you put on a
respirator to check that it has been donned correctly.
Remember, always follow the respirator
manufacturer’s instructions for the specific
respirator model that you are using.
Here are some general instructions for
properly donning and doffing and properly
conducting a user seal check for the two
most common types of respirators.
Let’s begin with general instructions for a
disposable filtering facepiece respirator,
which is often referred to as an “N95” or a
“dust mask”:
Inspect the respirator, including the straps,
for tears or damage. If you find any damage
to the respirator, replace it. If your respirator
comes out of its original container folded
flat, open the folds fully, following the
manufacturer’s instructions.
Using one hand, place the respirator on your
face with the nosepiece at your fingertips,
allowing the headbands to hang freely. The
nosepiece should span and cover the bridge
of your nose, and the respirator should cup
your chin.
Pull the top strap over your head, resting it
high at the back of your head. Pull the
bottom strap over your head and position it
around your neck and below your ears. Be
sure not to criss-cross the straps. Make sure
that your mouth and nose are covered
by the respirator.
If the nosepiece has a metal nosepiece or
strip, use both hands to mold the nose strip
to conform to the shape of your nose by
pushing inward while moving your fingertips
down along both sides of the nosepiece.
Next, conduct a user seal check. It’s
essential to follow the manufacturer’s user
seal check instructions because the
manufacturer knows the best method for
checking their respirator.
Generally speaking, the manufacturer’s
instructions are based on covering the
surface of the respirator, usually with your
hands, so that air is prevented from passing
through the filtering facepiece. A positive
pressure seal check is performed by gently
exhaling to see if the facepiece bulges
slightly. For a negative pressure seal check,
take a quick, deep breath to see if the
facepiece collapses slightly.
During either test, if air leaks out between
your face and the respirator’s faceseal, the
respirator may not fit your face properly.
One way that you can identify leakage is if
you feel air blowing through the seal onto
your face or eyes. If you feel leakage,
readjust the fit of your respirator and check
the seal again.
If you cannot achieve a proper seal, you are
not protected and should not enter a
hazardous area. See your supervisor to
determine what the problem may be.
When you’re finished wearing the respirator,
carefully remove it without touching the
exterior, because the exterior may be
contaminated. Discard your respirator
according to your company’s procedures.
Now, let’s explore the general instructions
for properly donning and doffing and
properly conducting a user seal check for a
half facepiece elastomeric respirator,
sometimes referred to as a “half mask.”
Remember, these are just general
instructions. You should always follow the
manufacturer’s instructions for the specific
respirator model that you are using.
To begin, inspect the respirator, including
the straps, valves, and gaskets, for loose,
missing, or damaged parts. If you find any
damage to the respirator, repair or replace it.
Then, pull the bottom strap over your head.
Place the respirator facepiece under your
chin and over your nose, with the narrow
part of the facepiece over your nose.
Pull the head harness over the crown of your
head and adjust its placement until it is
stable, but comfortable.
Be sure that the neckstrap is flat and smooth
against the back of your neck. Adjust the
neckstrap, but be careful not to over-tighten
the respirator to your face.
Next, perform a positive pressure user seal
check. Place the palm of your hand over the
exhalation valve outlet. Do not push so hard
that you distort the natural shape of the
facepiece. Exhale gently and hold your
breath to create and maintain a slight
positive pressure inside the facepiece. If the
facepiece bulges slightly and no air leaks are
detected between your face and the
facepiece, a proper fit has been achieved.
If, on the other hand, you detect faceseal
leakage, reposition the facepiece and
readjust the straps, and then retest. If you
cannot achieve a proper seal, you are not
protected and should not enter
a hazardous area.
See your supervisor to determine
what the problem may be.
Next, perform the negative pressure seal
check. Cover the respirator cartridges or
filters with the palms of your hands. Inhale
gently. If you feel the facepiece collapse
slightly and pull closer to your face with no
leaks between the face and facepiece, a
proper seal has been made. If you detect
faceseal air leakage, reposition the respirator
on your face and readjust the straps, then
recheck. If you cannot achieve a proper seal,
you are not protected and should not enter a
hazardous area. See your supervisor to
determine what the problem may be.
When you have finished wearing the
respirator, carefully remove it by loosening
the straps and taking it off without touching
the cartridges or filters, because they may be contaminated.
Follow your company’s procedures for
maintenance of the respirator, including
proper cleaning and disinfecting and storage.
Remember, respirators must be used in the
context of a comprehensive respiratory
protection program, according to OSHA
standard 29 CFR 1910.134.