From 1964-1965 NASA conducted a series of nine experiments in "minimal personal hygiene" at the Wright-Patterson Air Force Base in Ohio. Minimal was defined as "no bathing or sponging of the body, no shaving, no hair and nail grooming...no changing clothes and bed linen, the use of substandard oral hygiene, and minimal use of wipes" for, depending on the experiment, anywhere from two to six weeks.