actually very feasible and only required checking every few minutes (more often during exercise and when close to the surface perhaps). He developed a successful prototype, initially using two oxygen sensors in two separate larger blocks. With the availability of miniature readouts, he advanced the design to use a triple oxygen sensor system in order to allow there to be a "voting ability" for which sensor was malfunctioning if there was an error in one. He continued to innovate, including at one time experimenting with a "hands-free" tongue-based oxygen injection system he wryly called the "snog valve". He then perfected the system over several years, building further prototype units that were test dived by friends Natasha Dickinson and Daniel Reinders. In time he came to see the potential for commercial sales of the system, and began Jetsam technologies. Over time, he would begin to explore also a smaller recreational-sized version of the KISS rebreather as well. He also pursued a pneumatic air compressor system for rebreathers, whereby partially full standard scuba tanks could be used to top-up the smaller rebreather tanks without the need for a motorized compressor. See also KISS Principle Rebreather References External links History of Jetsam Gordon Smith, popular inventor of the KISS rebreather, dies from illness, by Andy Carroll, January 12, 2006, Scuba Geek 1950 births 2006 deaths People from Flin Flon 20th-century Canadian inventors