of the Gemini space suit with a colleague in a pure oxygen chamber at Brooks Air Force Base in San Antonio, Texas, when a fire broke out, destroying the chamber. Smith and his partner narrowly escaped. On November 17, 1962, a fire broke out in a chamber at the Navy's Air Crew Equipment Laboratory during a pure oxygen test. The fire was started because a faulty ground wire arced onto nearby insulation. After attempts to extinguish the fire by smothering it, the crew escaped the chamber with minor burns across large parts of their bodies. On February 16, 1965, United States Navy Divers Fred Jackson and John Youmans were killed in a decompression chamber fire at the Experimental Diving Unit in Washington, D.C., shortly after additional oxygen was added to the chamber's atmospheric mix. In addition to fires with personnel present, the Apollo Environmental Control System experienced several accidents from 1964 to 1966 due to various hardware malfunctions. Notable is the April 28, 1966 fire, as the subsequent investigation found that several new measures should be taken to avoid fires, including improved selection of materials and that ESC and Command Module circuits have a potential for arcing or short circuits. Other oxygen fire occurrences are documented in reports archived in the National Air and Space Museum, such as: Selection of Space Cabin Atmospheres. Part II: Fire and Blast Hazaards in Space Cabins. (Emanuel M. Roth; Dept of Aeronautics Medicine and Bioastronautics, Lovelace Foundation for Medical Education and Research. c. 1964–1966) "Fire Prevention in Manned Spacecraft and Test Chamber Oxygen Atmospheres". (Manned Spacecraft Center. NASA General Working Paper 10 063. October 10, 1966) Incidents had also occurred in the Soviet space program, but due to the Soviet government's policy of secrecy, these were not disclosed until well after the Apollo1 fire. Cosmonaut Valentin Bondarenko died on March 23, 1961, from burns sustained in a fire while participating in a 15-day endurance experiment in a high-oxygen isolation chamber, less than three weeks before the first Vostok crewed space flight; this was disclosed on January 28, 1986. During the Voskhod 2 mission in March 1965, cosmonauts Pavel Belyayev and Alexei Leonov could not completely seal the spacecraft hatch after Leonov's historic first walk in space. The spacecraft's environmental control system responded to the leaking air by adding more oxygen to the cabin, causing the concentration level to rise as high as 45%. The