Posted by NickD (24.241.112.117) on April 19, 2001 at 08:52:53:
In Reply to: O2 mask type posted by John on April 19, 2001 at 01:22:27:
If the mask has two valves, it can be converted to a one check valve mask with a piece of tape. Both diaphagms can be removed from a two valve mask where you will inhale the raw 02 plus room air from the two opened valves. I find this way too weak, and sometimes both those rubber disks will fall off and the O2 is not effective.
On the other hand with both disks on or one with a one check valve masks, the O2 of which you will be getting 100% of is very strong and can burn your lungs. So I leave one valve open that seems the best for me. When I first put the mask on, I can block that opening with my fingers and take a couple of deep breathes of pure O2 to get started hold my breathe for about 30 seconds until my lungs can take in that raw O2, then release the finger pressure that cuts the intake pure O2 ratio.
You can also block some of the holes on the check valve with RTV, By experimenting like this you can control the percentage of pure O2 intake. I shoot for the strongest O2 concentration I can stand without excessive throat and lung burning. No sense in helping one thing in your body while hurting another, breathing pure O2 for even a couple of minutes can cause your blood to boil, still need some nitrogen to calm things down. Believe me, you can feel the effects.