From: mshaw@panix.com   
      
   J.D. Baldwin  wrote:   
      
   > Now, this is something I do happen to know a little bit about. A NRB   
   > mask delivers 60-90% inspired concentration of the gas being delivered   
   > at 15 l/m. At the *low* end of that delivery range, the inspired gas   
   > is going to be 92% N2. That will always, always, always be lethal, and   
   > pretty quickly so. You will probably deliver more N2 -- again, even   
   > assuming the NRB is operating at the bottom of its range -- than you   
   > could in any "gas chamber" you could realistically construct. There is   
   > simply no reason for that.   
      
   Interesting, and contrary to my crossthread guess. How do you keep   
   the mask from leaking O2 - well, room air - into it? Or will such   
   leakage simply not be enough to matter?   
      
   Positive pressure differential? I think that that would make sense.   
      
   --   
   Mark Shaw                                        moc TOD liamg TA wahsnm   
   ========================================================================   
                        "Anyway, we delivered the bomb."   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)