428-GX-USN 1163593:   U.S. Naval School of Diving and Salvage, Washington Navy Yard, Washington, D.C.   U.S. Navy men keep close watch on the gauges denoting oxygen used by the divers while they are making a dive during open sea helium and oxygen training dives.   Photographed by PH1 (DV) S.L. Waterman, July 1975.  U.S. Navy Photograph, now in the collections of the National Archives.  (2016/06/14).
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