November 22 this year in Russia, in St. Petersburg from the master to repair domestic refrigerators oxygen cylinder exploded. Cylinder was 1 liter, examined by the working pressure 250 bar cylinder, but the cylinder was loaded with up to 170 bar. The man disconnected the empty cylinder connected the complete, slowly opened the valve to check the cylinder pressure per the pressure gauge and the explosion occurred.Valve with reducer punched a hole in the car and flew off in an unknown direction. The explosion shattered the man hand (well, that he was in shock myself unable to put a bandage to stop bleeding), and later at the hospital amputated hand. In the wizard experience over 30 years. Be careful!