In Reply to: Space Walking and the Bends posted by Elaine on July 30, 2005 at 04:34:30:

The reason for the hyperbaric stuff is only for the spacewalk in the EVA suits. If they weren't doing that, they wouldn't be playing with the pressure in the shuttle (I think). The EVA suits need to be lower pressure so there is some dexterity in the suit joints, especially the gloves. I think the suits have an internal pressure of like 4-5 PSI, so you're essenitally going from sea level to something pretty high, and need to make a stop on the way. They make that stop in the shuttle, breathing pure O2.