Re:The Book said it (Score 1)

Actually a small group of human test subjects involved in a project known as "Metabolic Factors" performed at Brooks AFB in summer 1966 helped save the the Apollo 13 crew. This research project was focused on the levels of CO2 humans could endure and still perform complex task, like maneuver a space craft. The results of this testing were significant in determining how effective the 'ad hoc' CO2 scrubber the crew built needed to be. This allowed the crew to stretch the utilization of available O2 to the max. I know this because I am one of those test subjects and my parents were proud of the letter they received from the Air Force. we all played our part in the mission....