XPost: sci.space.policy, sci.physics   
   From: jfindley@cinci.nospam.rr.com   
      
   In article <1q2uvbliqtpcvf8fe057sqoomncsigdsj7@4ax.com>,   
   fjmccall@gmail.com says...   
   > No, you don't.  From your own cite, the problems occur when you have   
   > oxygen partial pressures of 0.5 bars (around 7.25 psi) or higher. Note   
   > that these problems will occur when you get to those sorts of O2   
   > partial pressures whether you have 'cut the O2' with something else or   
   > not.   
   >   
   > Normal partial pressures of O2 in the atmosphere are around 3 psi.  A   
   > 3 psi pure oxygen atmosphere won't hurt you, since it's the same   
   > partial pressure of O2 that you get at sea level on Earth.  Pretty   
   > much ALL US space missions before the Shuttle (the exception is   
   > Skylab) were flown with pure O2 atmospheres.   
   >   
      
   And Skylab used a 74-percent oxygen and 26-percent nitrogen breathing   
   mixture at 5 pounds per square inch (versus 14.7 pounds per square inch   
   on Earth).  Cite:  http://history.nasa.gov/SP-400/ch2.htm   
      
   So you do *not* need a "breathable" atmosphere that is mostly N2.   
      
   Jeff   
   --   
   All opinions posted by me on Usenet News are mine, and mine alone.   
   These posts do not reflect the opinions of my family, friends,   
   employer, or any organization that I am a member of.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)