Sorry this is long, buuut ... I recommend going to
http://www.northland.cc.mn.us/Terry_Wiseth/gas%20transport%20part%201/index. htm Keep in mind that there are all sorts of hyperbaric chambers available. There are others that are smaller but not capable of great pressures. The only one I was in was a large one on City Island NY which took us down to the equiv of 160 ft under the ocean. It was capable of going much deeper. Assuming 33 ft of depth in salt water for every 1 atmospheric pressure, 160 ft is roughly 4.8 atmospheres or 71 lbs/in^2. They were doing alot of work with fire fighters who had succumbed to smoke inhalation. Depending upon the medical case involved, they can go as high as 4 atmospheres. One case there involved a motorcycle accident victim with a crushed knee. Had he remained in the hospital, he would have lost his leg. In the chamber, the partial pressure of O2 was high enough so that the little amount of blood that got around the injury managed to keep the tissue alive and eventually saved his leg. Oh, yea, the doc got stuck in there with the victim for the duration. On another note - Look up Pashen's Law to get a rough idea what you're up against. It goes roughly like this - Paschen's Law: breakdown for uniform gaps V(kV)= 24.2Sh +6.1(Sh)^0.5 where V is the breakdown voltage in KV S=(293p)/760T h is electrode spacing in cm. p is pressure mm of mercury T is temperature in degrees Kelvin At STP, S = 1 so 30KV/cm is a pretty good approximation for 1 cm. At 1, 2, 3, and 4 atmospheres for 1 cm it goes something like this ... Atmospheres separation (cm) Breakdown voltage (KV) 1 1 30 KV 2 1 57 KV 3 1 83 KV 4 1 109 KV The reason for the increase in voltage threshold is due to more charge carriers being present for charge transportation across the gap. Neon lights won't work at elevated pressures inside the tube. The inside has to be evacuated to a partial vacuum get the light to glow. You may also want to check for the flammability of materials at elevated percentages of O2. Side Note: The use of pure O2 during Apollo 1 and the earlier space flights like Mercury was merely a copy of using pure O2 in planes before the space program. Up until that point in time, there was nothing unique nor unusual about using pure O2. --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
