01554oam 2200433 a 450 991070187530332120120524120347.0(CKB)5470000002421353(OCoLC)794227711(EXLCZ)99547000000242135320120524d2010 ua 0engurbn|||||||||txtrdacontentcrdamediacrrdacarrierBrass compressed gas cylinder valves and associated fittings used in refuge alternatives[electronic resource][Arlington, Va.] :[U.S. Dept. of Labor, Mine Safety and Health Administration],[2010]1 online resource (10 unnumbered pages)Program policy letter ;no. P11-V-17Title from title screen (viewed on May 24, 2012)."Effective date 11/04/2011.""Expiration date 03/31/2013."Coal mines and miningUnited StatesMines and mineral resourcesUnited StatesMine accidentsUnited StatesMine safetyUnited StatesCoal mines and miningMines and mineral resourcesMine accidentsMine safetyUnited States.Mine Safety and Health Administration.GPOGPOGPOBOOK9910701875303321Brass compressed gas cylinder valves and associated fittings used in refuge alternatives3157492UNINA