A drink tube clean enough to drink from.

THAT SOLDIER SHOULD HAVE PAID MORE ATTENTION TO KEEPING THE DRINK TUBE CLEAN.

Imagine how gross it would be to drink through the same straw day after day. It will be equally gross if you don't keep the drinking tube in your M40 or M42 mask clean. Lots of nasty stuff can form in the tube over time and you end up drinking it in. Keeping the tube sanitary doesn't take that much effort.

Simply flushing the tube with water will get rid of most gunk. Be sure to remove the filter canister before flushing. Fill your canteen with clean water and attach it to the external drinking tube. Turn the canteen upside down and squeeze it while holding the facepiece upside down with the internal drink tube facing away from the facepiece. Do this until all the water runs through the drinking tube. Do this twice.

But if you've been training with your mask quite a bit, the tube may need more serious cleaning. Get calcium hypochlorite, NSN 684000-242-4770, from your NBC NCO. It's part of the expendable supplies for the masks. Mix 1/2 teaspoon of the hypochlorite with a gallon of clean water and fill your canteen with the mixture. Make sure the hypochlorite is completely dissolved. Run the mixture through the drinking tube and then run 2 canteens of clean water through the drink tube.

THESE PROCEDURES CAN BE FOUND ON PAGE 2-77 IN TM 3-4240346-20&P

Never drink anything but water through the drinking tube. Stuff like sports drinks will really foul the tube.

NBC NCOs, when you're issuing a used mask to a new soldier, put on a new internal drinking tube. Tubes are cheap and a new tube helps stop the spread of germs.

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