This definition appears somewhat frequently
See other definitions of ASA
Samples in periodicals archive:
Title : The nudist: sunshine & health; Artist: Williams, Carl Easton (editor.) | Knapp, Alois S. | Young, Robert J. (donor.) | American Sunbathing Association...
Yes, I know that every kid is a nudist. But I really was one. Like, officially. As in, card carrying member of the ASA (American Sunbathing Association.)