In 1946 Bradner took a position at U.C. Berkeley that required him to dive. He consulted with U.S.N. frogmen on their experiences of loss of body heat and investigated the concept of thermal protection using a suit of insulated foam material which trapped water that warmed to the body's temperature.
The material was neoprene. He worked on developing the new suit in the basement of his family's home in Berkeley.
By 1952 he had perfected his concept using neoprene and he and other engineers founded the Engineering Development Company (EDCO) in order to develop the wetsuit. Bradner and his colleagues tested several versions and prototypes of the wetsuit at the Scripps Institution of Oceanography in La Jolla, California. Bradner applied for a U.S. patent for the wetsuit, but his patent application was turned down due to its similar design with a flight suit.
The United States Navy did not adopt the new wetsuits because of worries that the neoprene might make its swimmers easier to spot by underwater sonar.
In 1961 Bradner joined the Scripps Institute of Geophysics and Planetary Physics as a geophysicist. He became a full professor in 1963 and retired in 1980. Bradner never patented his invention and never benefitted from it financially.
Others divers went on to develop successful neoprene wetsuit product lines for diving and surfing. His invention of the wet suit was a giant leap forward for diving and was adopted around the globe.
Hugh Bradner died in San Diego, California in 2008.