Joseph F. Shea, ASPO Manager, approved Crew Systems Division's recommendation to retain the "shirtsleeve" environment for the CM. The design was simpler and promised greater overall mission reliability; also, it would be more comfortable for the crewmen.

Wearing part of the space suit would compound problems with humidity and condensation inside the cabin. Accordingly, the crew would be clad only in their constant-wear garments or would be fully suited. (MSC and North American had explored the feasibility of putting a water separator in the cabin heat exchanger for airframe 012. It was hoped that, through partially suited operations, the crew could gain confidence in the spacecraft's pressurization system. North American advised, however, that considerable cost and schedule impacts could be expected. Moreover, such a device would be only partly successful -condensation would still be a major problem, Shea therefore vetoed the water separator and the idea of partially suited operations during the first manned Apollo flight.)