limits of chlorination at that time, behavioral measures were used to maintain water quality. In 1933, in addition to recommending nudity, all bathers were required to empty their bladder and shower before entering the pool. Those suffering from skin or repiratory disease were prohibited from using the pool. In 1940 health experts continued to favor boys wearing bathing suits only in pools visible to both sexes. Girls were issued cotton suits that could be boiled to disinfect them between uses; the wool suits used by boys could not because they would shrink. It was also noted that wool suits that had previously been used in salt water could not be washed effectively because salt prevents soap from lathering. In 1926, the American Public Health Association (APHA) standards handbook recommended that indoor swimming pools used by men adopt nude bathing policies and that indoor swimming pools used by women require swimsuits "of the simplest type". Students bringing their own suits was discouraged, the institutions not having control of decontamination. In 1947 girls at the Liberty School in Highland Park, Michigan, also swam nude in their classes. Boys not having worn suits for years, girls requesting to do the same in order to give them more time in the pool rather than changing. After six weeks, the girls in the middle school were ordered to wear suits, but the elementary school girls continued to be nude. While following the wishes of parents who believed older girls should behave modestly, all the board members disagreed, stating that there was "no moral issue involved". New developments in pool chlorination, filtration, and nylon swimsuits led the APHA to abandon its recommendation of nude swimming for males in 1962. However, the custom did not immediately cease. During the 1970s, the adoption of mixed-gender swimming led to the gradual abandonment of nude male swimming in schools. Federal Title IX rules mandating equality in physical education led most schools to switch to co-educational gym classes by 1980, ending nude swimming in public schools. In the 21st century, the practice has been forgotten, denied having existed, or viewed as an example of questionable behaviors in the past that are no longer acceptable. However, Jungian psychoanalyst Barry Miller views the sexualization of nudity in male only situations such as locker rooms and swimming pools as a loss. Contemporary practices In many countries in the 21st century, nude swimming mostly takes