*Cleaning of M40 Series Protective Mask*
By: Skid600

1. The easiest way to disassemble your mask is to start with the Head Harness. Taking this off is easy. All you have to do is slide the straps out and turn the ends just a little sideways to pull them through the buckles.
2. Once you have the Head Harness off, turn the hood back over the mask and remove the Eyepiece Outserts. They can just be pulled off, if you have trouble removing them slide a finger around the edge and pop out the rubber at one of the corners then pull them off.
3. Next remove the Filter. Just twist it off counter-clockwise.
4. Next remove the Outlet Valve Cover. To do this you pull the External Drink Tube out of the Cover then lift up gently on the bottom of the Cover. Once the bottom is up, work the Cover off the two tabs. Be careful not to rip the cover.
5. Next remove the Side Voicemitter Retaining Ring. Again twist counter-clockwise. If it is tight, use the D-Ring on the long strap of the Mask Carrier. Once the Retaining Ring is off, reach inside the mask and gently push out the Side Voicemitter. Be careful not to dent the inside of the Voicemitter. Finally pull out the O-Ring.
6. Next remove the Eyelense Outserts, just pull them off.
7. Now you’re ready to remove the Hood with Second Skin. Detatch the velcro on both sides of the Outlet Valve. Once that’s done, turn the mask inside out and grab hold of the Facepiece at the top and gently work the Second Skin over the Eyepieces, the Front Voicemitter and the Outlet Valve Seat. Note: Some masks have a one-piece hood with second skin attatched. There is a newer version that is called a Quick Doff Hood with a separate Second Skin. I prefer the latter because it is easier to remove and replace the quick doff hood. If you have one of the quick doff hoods, you can remove that at any time and remove the second skin at this step.
8. When you have the hood off, you need to remove the Outlet Valve Disk. Do this by pulling it out carefully so you don’t break the post on the disk.
9. Next you need to remove the Inlet Valve Assembly. I do this by pushing from the outside on the Inlet Valve Wheel (being careful not to break any of the spokes) so that the whole thing is on the inside of the mask. Once that is done, reach inside and pull the Airflow Deflector off the pins one at a time. Make sure you don’t tear the Airflow Deflector Flanges when removing it. When you have it out, you can disassemble that by just pulling off the wheel first, then pull off the Inlet Valve Disk.
10. Once that is out, you remove the Internal Drink Tube by simply pulling it off the mounting post.
11. The last things you remove are the Nose Cup Disk Valves, there are 2, one on each side of the Nose Cup. Simply pull them out of the Disk Valve Seat. Again be careful not to rip or tear them, or to pull off the post on them.
12. Now, if I haven’t told you how to remove something, that’s because it should never be removed. Examples are: the Front Voicemitter, the Nose Cup Disk Valve Seats, the Nose Cup and the External Drink Tube. These things should NEVER be removed under any circumstances!!!

1. Cleaning your mask is really very simple. You only need a few items to do it properly. You need some type of detergent or soap (dish soap will work,) bleach, a lint-free cloth, a scrub brush and three 5 gallon pails.
2. To set up you want to fill the first pail with HOT soapy water. The second pail gets HOT water mixed with bleach, you don’t need much bleach (it should be about a 5% bleach solution guestimated.) And the third pail gets just warm water.
3. With all cleaning steps you will first dip the part in the soap solution and scrub with the cloth to clean it, second dip into the bleach solution and scrub to sterilize and third you dip into regular water and swish it around to get off excess bleach and detergent. After the part is clean you set it somewhere, preferably in a sunny and warm place to dry.
4. The first thing I usually clean is the Hood because it takes the longest to dry. After it’s clean find somplace to hang it so it can drip dry.
5. Next is the Facepiece, you don’t want to actually dip the facepiece in any of the pails because water can get in and rust can form around the Front Voicemitter or the Eyelenses which would cause a bad seal. What you want to do with this is use the lint free cloth, dip that in the solutions and scrub the entire facepiece, making sure to get into all the nooks and crannies.
6. After that, all the indiviual pieces can be cleaned in whatever order you choose. Just make sure that you DO NOT get the Filter wet, if you do, you will have a useless filter.
7. Finally, clean your Carrier using the scrub brush. You do not want to soak your carrier because it can ruin the material. Just brush off all the dirt/stains (you can dip the brush, but not the carrier) and also clean out the inside of the carrier to remove all dirt/sand.

1. Once all the pieces are completely dry, you can begin reassembly. You do not want to assemble the mask with wet components because mold could form and deteriorate the mask.
2. I like to reassemble the mask by starting on the inside with the Inlet Valve and Airflow Deflector. To do this you need to put these three pieces back together. First take the Inlet Valve disk and slide it onto the Airflow Deflector, you should notice that there are two lips where the valve disk could sit. You want to slide it over the first so it is seated on the second lip. Next take the Inlet Valve Wheel and check it to ensure that all spokes are present and undamaged, also check to ensure that it is not cracked or deformed. Then install it over the valve disk with the two "longer/taller" spokes up. Now that that is together, take the whole thing and slide it into the side of the mask that you want the filter on (right handed firers should put filter on left side and left handed firers should put it on right side.) Start with the flange furthest from you and push the pin on the airflow deflector through the little hole in the flange on the mask. Then work the other pin through the flange nearer to you. Once both pins on airflow deflector are seated properly, go to outside of mask and gently pull the inlet wheel through. Once it is through, gently push on the edges of the wheel so that it is seated snugly around the inlet hole. Make sure that it spins with little resistance.
3. Next I like to put in the Nose Cup Disk Valves (the 2 black disks with pin.) These are simply put with the disk on the inside with the pin pushed through the center of the valve seat then pulled from other side untill they "snap" into place, you should feel it go in.
4. After that I go to the Outlet Valve Disk (the white/clear disk similar to nose cup disks only larger.) From the outside of mask, push the pin through center of outlet valve and reach inside mask with thumb and forefinger and grip the pin and gently but firmly pull it through while pushing from the other side, be very careful not to tear the pin off. If you have larger hands, you can try using needle nose plyers, but you must be very careful not to rip the disk.
5. Now you can put in the Internal Drink Tube, but first check to ensure that it is not cracked, ripped or torn and also make sure it is not blocked (blow through one end.) To reinstall this, take the smooth end and slide it over the drink tube mount until it is seated firmly in place. Then rotate it where it can be easily worked into mouth while wearing the mask.
6. Before we move to the ouside of the mask, you must check to ensure that the Nose Cup itself is seated properly. It should not be loose around the front voicemitter or around the outlet valve area either (the area where the internal drink tube mount is) There is a lip here that the nose cup should be seated under, take your thumb or finger and gently push the nose cup down in a circular motion and it should slide into place.
7. Now we can go to the outside of the mask, it is time to install the hood (or the separate second skin with the hood going on last.) Before installing the hood, check it for noticeable cuts, tears, or rips. Also hold it up and look through the inside, if you see a lot of small holes, you should replace it, a couple pin holes are fine. You want to install the hood so that the velcro will be on the outside. I like to get the hood turned right side out, then slide the mask in from behind. I find it is easier to put the hood/second skin around the front voicemitter first, then stretch the hood around the eyepieces and last around the outlet valve seat, make sure the external drink tube is on the outside of the hood/second skin when you secure the velcro tabs.
8. After that, you can put in the side voicemitter assembly. Start with the O-Ring making sure that it is not cut, cracked or torn you slide it into the port opposite where the filter will go. Next check the side voicemitter to make sure that it is not dented and put that in over the O-Ring. It should be installed black side (one side shows black, the other shows brass) or "nipples" (the nipples are four little things on the black side of the voicemitter) out. Next put the Retaining Ring on and tighten it using the D-Ring on the long strap of your Carrier. You want it tight enough that you cannot remove the retaining ring by hand.
9. Next you can put on the Eyepiece Outserts. Check the outserts to ensure they are not cracked or scratched so bad you can’t see through them and the rubber is not torn. Install them by flipping the rubber up onto the outsert then putting the outsert in place and flipping the rubber down so the outsert is secure. After they’re in place, wiggle them a little to ensure they’re seated properly.
10. Time for the Outlet Valve Cover, make sure it is not ripped or torn so badly it won’t stay on. Small rips or holes in the cover are ok (it is basically there to protect the outlet valve disk.) Put it on by putting the pins on the seat through the holes in the cover, then pull down on the bottom of the cover so it is seated firmly around the edge of the outlet seat. Put the end of the external drink tube in the space in the side and snap the tube itself into the space under the outlet valve cover.
11. Now install the Filter Canister. Twist it on clockwise until it is snug.
12. Finally, flip the hood over the mask and lay the mask down with the side that goes towards your face up and the chin of the mask towards you. Check the Head Harness to ensure there are no cuts or frays also check for elasticity. Lay the Head Harness on the mask with the sewn portions up and the tab towards the chin of the mask. Slide each strap through the buckle, first under the moving portion of the buckle then back through over the moving portion of the buckle so the loose end of the strap is out.
13. You should now have a clean and functional mask.

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