TM 3-4240-280-10

WARNING (CONT)
Canister insert filter MUST be already installed in canister. Filter insert prevents
leakage of dust particles during operational use.
If you become overheated in very cold weather, do not remove your facepiece
outdoors until your head cools and any sweat has dried. Frostbite may result if the
facepiece is removed while your face is still wet. These precautions are not
required if you are in a warm snelter.
Keep mask dry. Moisture could clog the canistef and make it useless. Moisture
could also short microphone connectors, which could cause a loss of communication
in the tank or aircraft.
Keep face clean shaven. An unshaven face could cause a bad seal between face
and facepiece.
Do not expose your facepiece to temperatures above 120”F
(48.89°C). If facepiece is exposed to air or water
temperatures above 120”F, allow lens to cool below 120”F
for at least 15 minutes before flexing or stowing mask in
carrier. After cooling, check lens carefully for cracks,
especially around periphery.
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