PADI Co-Founders, Ralph Ericson and John Cronin (From left to right) John Cronin, A Scuba Equipment Salesman for U.S. Divers, and Ralph Erickson, an educator and Swimming instructor, were concerned About The Scuba Diving Industry. They felt that the current scuba certification agencies were unprofessional, didn't use state of the art instruction and made it unnecessarily difficult for people to enter the sport. John and Ralph knew there had to be A Safer, Easy Way for People to Learn to. Breathe Underwater.