UNITED STATES MARINE CORPS
Field Medical Training Battalion
Camp Lejeune
FMST 1221
M-40 Field Protective Mask
Terminal Learning
Objectives
1. Given
the current M40 series field protective mask and carrier, spare parts, and
cleaning materials, maintain the M40 Field
Protective mask, to
ensure serviceability. (FMST-FP-1221)
2. Given
a tactical scenario in any combat environment, the current M40 series field
protective mask in its carrier and an NBC alert or an order to mask,
don the M40 field protective mask,
to provide timely NBC protection. (FMST-FP-1222)
Enabling Learning
Objectives
1. Without
the aid of references given a description or title
identify the components of the M40 field protective mask,
per the student handout. (FMST-FP-1221a)
2. Without
the aid of references given an M40 field protective mask and exposure to
irritant gas in a chamber or simulated combat environment,
don and clear the mask,
per the student handout. (FMST-FP-1222a)
1. M40
FIELD PROTECTIVE MASK (FPM)
Characteristics of the M-40 FPM
- The M-40 FPM is used to
protect the individual’s face, eyes, and lungs against field concentration of
chemical and biological (CB) agents, toxins, and radioactive fallout particles.
- The
M-40 FPM will not protect the wearer against industrial gases such as ammonia or
carbon monoxide. It is not effective in confined spaces, where the oxygen
content of the air is low.
- The
M-40 FPM allows the wearer the capability of drinking water while worn.
- The
M-40 FPM comes in three sizes: small, medium and large. The size mark is
located on the top left portion of the mask.
Components of the M-40 FPM
When you receive a FPM you
should inspect the following components for serviceability (see figure 1):
Face-piece Assembly
- foundation
of the protective mask. Everything else is attached to it. The face-piece fits
closely against your face to form a seal. It is made of silicone rubber.
Visually inspect interior and exterior surfaces of face-piece for dirt, mud, and
greasy or oily substances. Check face-piece for holes, tears, and splits by
holding it in front of a light source. Look closely at edges of face-piece.
Check for soft or sticky spots. Check silicone rubber next to eye lenses to be
sure they will not pull away from the face piece. Also check all face-piece
housings to be sure silicone is not pulling away.
Head Harness
- these adjustable straps are attached to the face-piece. When adjusted
properly, they will secure the face-piece to your face creating an airtight
seal. It consists of a head pad; forehead straps, temple straps, cheek straps,
and donning tab. Check the head harness for loss of elasticity and dirt. Check
straps for cuts, tears, missing parts, or deterioration such as mildewing or
fraying. Look at the buckles for bends, cracks, or corrosion. Check for
missing or broken buckles. Make sure finish on buckles is not chipped or
scratched exposing bare metal.
Eye-lenses, Eye-rings and
Out-serts -
made of clear plastic or ballistic glass and enable you to see clearly while
wearing the mask. Check eye-lenses for cracks, scratches, or discoloration that
affect vision. Check eye-rings for distortion or corrosion. Clear and neutral
gray eye lenses out-serts are provided with the mask. The purpose of the out-sert
is to protect the eye-lens from damage and to reduce fogging in cold weather,
neutral gray out-serts reduce glare. There are separate out-serts for left and
right eye-lenses. To install the out-sert, fold back the rubber apron, place it
over the eye-lens, and fold the apron back into place. Check both sets of out-serts
for cracks, chips, or discoloration that affects your vision. Check rubber
aprons for tears, looseness, brittle spots, soft or sticky spots or cracked
rims.
Canister
- filters chemical and biological agents and other particles from contaminated
air. It can be quickly and easily replaced and may be installed on either side
of the face-piece to allow use by left-handed or right-handed shooters. Do not
allow the inside of the canister to become wet. A wet canister is useless.
Check the canister, especially around the seams, for cracks, dents, or holes,
and damaged threads. Ensure the air intake is not clogged with dirt. Shake the
canister and listen for any signs of loose absorbent particles. The canister is
installed into the side port of the face piece, over the inlet valve. Tighten
the canister hand tight by turning clockwise.
Outlet Valve Disk and Outlet
Valve Cover -
releases exhaled air and prevents unfiltered air from entering the face-piece.
Do not use the mask if the outlet valve disk is missing or damaged because the
face-piece will leak. The outlet valve cover protects the outlet valve disk and
secures the external drinking tube. To check the outlet valve disk, grasp the
tab on the bottom of the outlet valve cover and lift. Check to see if the
outlet valve disk is present and is not curled or distorted. Place your thumb
on the disk and rotate it to make sure it is not sticking. Do not remove the
outlet valve disk from the outlet valve. Look at the disk for nicks, tears, or
rips. Wipe off any moisture with a clean cloth. Check the outlet valve seat
for dirt. Smooth the outlet valve disk so it lies flat on the outlet valve
seat. Check the outlet valve cover for cuts, tears, or holes. Look at the
inside of the outlet valve cover for dirt or moisture.
Internal/External Drink
Tubes - the
M40 Field Protective Mask is equipped with a system which allows the wearer to
drink while wearing the face-piece. The internal tube is grasped by the
person’s mouth. The external tube has a quick disconnect coupling which
connects the face-piece to the NBC Canteen Cap. Check that both tubes are
present and are free of cracks or cuts. Ensure the internal drink tube has
proper alignment and the external drink tube has solid connections. Connect the
coupling to the canteen cap and blow air through the system to ensure it is not
clogged.
Airflow Deflector
- located on the inside of the face-piece below either the left or right eye
lens depending on the canister location. It directs inhaled air over the eye
lenses to prevent fogging. Check that the airflow deflector is securely mounted
inside the face-piece and that both flanges are in the mounting holes of the
face- piece and are not broken. Check the mounting holes for cuts or tears.
Inlet Valve Disk
- allows filtered air to enter the face-piece and prevents moist exhaled air
from entering the canister. Do not use the mask if the valve body or inlet
valve disk is missing. Check that the inlet valve disk and valve body are
properly mounted on the airflow deflector post. Blow on the disk to make sure
it is not stuck to the valve body. Ensure the disk is free of cuts, holes,
tears, or dirt.
Nose-cup Assembly
- inside the face-piece is the nose-cup. It has one nose-cup valve disk on each
side. The nose-cup allows filtered air to pass through the nose-cup valve disks
and into your respiratory system from the upper part of the face-piece and
directs exhaled air out through the outlet valve in the bottom of the
face-piece. This ensures good airflow, which prevents moist exhaled air from
fogging the eye lenses in cold weather. Check that the nose-cup and nose-cup
valve seats are free of dirt, cracks, cuts, holes, or tears. Check that the
nose-cup is securely attached to the back of the face-piece by gently pulling it
away. Rotate the nose-cup valve disks to be sure they are not stuck and check
them for curling or tears. Smooth the nose-cup valve disks over the nose-cup
valves.
Voicemitter
- the face-piece is equipped with a front voice-mitter, which transmits the
user’s voice outside the face-piece, and a side voicemitter, located opposite
the inlet valve, which aids in the use of communications equipment. Check the
retaining rings around both for corrosion, cracks, or nicks. Try to tighten the
retaining rings by hand to check for looseness. Ensure both voicemitters are
free of dents, cracks, punctures, or dirt and that the four beads in the center
of each voicemitter are facing outward.
Carrier
- provides for storage, protection, and carrying of the mask and additionally
authorized items. Check carrier for dirt, sharp edges, torn straps, broken
stitches on seams, or missing hardware. Make sure there are no pencil or pen
markings on the carrier. Mildew, solvents, or abrasive materials on carrier may
harm the face-piece. Check the Velcro for dirt or debris. Check metal hooks
and D-rings for bends or breaks that make them unusable.
Waterproof Bag
- keeps the mask dry when required by climate or mission. It includes rubber
bands for sealing and instructions for use. Storage of the mask in waterproof
bag can degrade the protective capabilities of the face-piece. You must remove
the face-piece as soon as protection of the mask is no longer required. Check
the waterproof bag for cracks, tears, holes, and brittleness. Food should not
come in contact with the waterproof bag because of possible toxic effects. It
is stowed in the left end pocket of the carrier.
Face form
- Maintains mask shape
Figure 1.
Components of the M-40 FPM
Accessories of the M40 FPM
M1 canteen cap
- contains a hole that
allows the external drinking tube to be connected to the canteen. Always check
that the surfaces are free of contamination before connecting the drinking
system.
M291 decontaminating kit
- used for personal decontamination. It will be discussed further during the
lesson covering MOPP Gear (FMST 1223).
Optical inserts
-
available by medical prescription for personnel who must wear
glasses. Do not wear eyeglasses or contact lenses with your mask. Check you
inserts for broken lenses, frame, loose screws, or becoming disconnected from
the face-piece.
2. USING THE DRINKING SYSTEM OF THE M40
FPM
Prior to using the drinking
system, use M8 chemical agent detector paper to check for contamination. If
contamination is detected, decontaminate the drinking tube and the M1 canteen
cap with the M291 decontamination kit. After decontamination, recheck the
surfaces with M8 chemical agent detector paper.
- By pressing in on the top of
the outlet valve, the internal drinking tube can be grasped between your teeth
(See figure 2a)
- Pull the quick connect
coupling out of the outlet valve cover (See figure 2b)
Figure 2a Figure 2b
- Remove the cap cover from the canteen cap (decontaminate if
necessary)
- With the canteen right
side up, insert the quick connect coupling into the M1 canteen cap and blow
air into the drinking system to create positive pressure within the canteen
(See figure 3)
- Raise and invert the canteen
and begin drinking water
Figure 3
3. FITTING THE
M40 FIELD PROTECTIVE MASK
Before the mask can be donned and cleared, adjustments must be
made to the head harness so that it fits properly. The adjustment steps are:
- Completely loosen all head harness straps and pull the head
harness over the front of the face-piece.
- Put your chin in the pocket and hold the face-piece against
- Grasp the donning tab and pull the head harness over your head.
Be sure your ears are between the temple and cheek straps.
- Be sure that the head harness pad is centered at the back of
your head. Straps should lie flat against your head.
- Tighten the straps with short-jerky pulls to the rear in the
following sequence: forehead straps, cheek straps, and temple straps. Ensure
the head harness pad stays centered at the back of your head.
-
Cover openings at bottom of the outlet valve with palm of
one hand. Breathe out hard so that air escapes around edges of face-piece.
- With the palm of your free hand, cover the inlet port of the
canister and breathe in. The face-piece should collapse against your face, and
remain so while you hold your breath. If it does, the face-piece is airtight.
If the face-piece does not collapse, check for hair, clothing, or other matter
between the face-piece and your face. Check that the head harness straps are
not twisted or that the head pad is not centered.
- Clear your face-piece again and recheck for leaks.
- To remove your face-piece, loosen the cheek straps only. Place
one hand on front of voicemitter to hold face-piece on face with the other hand
grasp the donning tab and pull the head harness over the front of the face-piece
and remove face-piece.
Masking Procedures
- when the verbal (“GAS! GAS! GAS!) or visual signal sign for an NBC attack has
been given, you must follow these procedures in a time limit of 9
seconds without hood
or 15 seconds with hood
or risk becoming
contaminated.
- Stop breathing and close your
eyes.
- Open carrier and grab the
face-piece. The mask is stored with the head harness pulled over the front of
the mask.
- Place your chin in
chin-pocket of the face-piece.
- Clear the field protective
mask
- Cover the
outlet valve with the palm of one hand.
- Exhale sharply
so that the air escapes around the edges of the face-piece
- Cover the air
inlet port of the canister with the palm of your free hand, and breathe in. The
face piece should collapse against your face and remain there while holding your
breath. If the face piece collapses consider it airtight.
- Grasp the tab
and tighten straps and adjust. Make sure the square harness patch is centered
in the rear of your head.
- Resume
breathing.
- After completing these steps the following actions should
be taken:
(1) Put on your helmet. Be sure not to upset the seal between
your face-piece and the side of your face when putting on helmet.
(2) Close the carrier.
(3) Continue your mission.
Unmasking -
remove your mask only when competent authority issues the
“UNMASK” command. The following steps accomplish this:
- Hold your rifle between your legs; remove your helmet placing
it on the ground next to you.
- Loosen cheek straps.
- Place one hand on the front of the voice-mitter-emitter to
hold the face-piece on your face and with the other hand grasp the donning tab
and pull the head harness over the front of the face-piece and remove the face
piece. Put your helmet back on your head.
- Continue your mission.
4. CARE
OF THE GAS MASK
Stowing the M40 FPM
-
properly stowing the mask will ensure that it remains serviceable
and easily accessible when your life depends on it. The following steps will be
used when stowing the mask in the M40 Carrier:
- Check that the eye-lens out-serts are installed on the
face-piece. Abrasives, such as sand and grit, will scratch the eye
lenses.
- Check that your face-piece is dry and free of oils and solvents
before stowing.
- Check that the interior of the carrier is free of dirt and
trash or other unauthorized items.
- Hold face-piece in a horizontal position.
- Pull head harness over front of face-piece.
- Hold the face-piece upright and put it in the carrier with the
lenses facing away from your body.
- Stow your other out-serts, waterproof bag, and operator’s
manual in the inside pockets of the carrier.
- Close the carrier.
- Store your face-piece in its carrier and put it in a cool, dry,
dark place, preferably hooking it on the short strap.
Wearing Your Carrier
There are three ways to carry the M40 Field Protective Mask and
Carrier:
- The shoulder carry.
- The leg carry. The following steps will be used:
- Put waist strap D-ring around waist and attach to hook
on carrier. Adjust strap.
- Bring leg strap from back and around inside of leg.
- Pass leg strap through round ring, hook to D-ring, and
adjust strap.
- The pistol belt carry.
Cleaning the M-40 FPM
- Wash mask anytime it needs
cleaning. A white or rust colored waxy film is not dirt; it is from the
preservatives built in the rubber. It will bleed off as long as the face-piece
is good.
- Required materials: soft
cloths, soft bristle brushes, warm soapy water, and warm clear water.
- Procedural Steps:
-Remove the canister by
unscrewing it from mask.
-Dip clean, soft cloth in warm
soapy water and wring it out. Wash mask inside and out. Wash voicemitter,
outlet valve cover, and inlet valve assemblies. Be careful with rubber disks.
- Rinse cloth in clear, warm
water and wring it out. Wipe all washed parts.
- Dry all parts and mask with
dry, soft cloth. Use brush in hard to reach areas.
- Replace parts taken off.
Make sure rubber disks are snug and flat. Clean the lenses using polish or
warm, soapy water.
Canister Replacement
Replace the canister if:
- It has been immersed in water.
- Canister has splits, or cuts, a bent or split thread connector,
or has been crushed.
- You feel excessive resistance to breathing and inspection shows
that the canister is clogged with foreign matter.
- After removing the face-piece you see charcoal dust on your
face.
- Your unit commander directs replacement of canister.
- The filter lot becomes unserviceable.
- Every 30 days after initiation to toxic chemical operations and
after each confirmed blood agent attack.
REFERENCES
Unit Maintenance Manual for
Chemical-Biological Mask M40, TM 09204A/09205A-20&P/4
REV: June 2008
M-40 Review
1. Describe the problem with
allowing water to get inside the canister.
2. List
three accessory items associated with the M-40 Field Protective Mask.
3. Identify
the first step in donning your gas mask once you have received word of possible
contamination.
4. Once the order is given to
don mask, how long do you have to don your gas mask without a hood. What about
with a hood? |
