NFPA 410-2020 Standard on Aircraft Maintenance.
5.9.6.2 A pressure gauge shall be provided downstream of the orifice as a means of indicating the pressure in the aircraft oxygen ssstein being filled.
5.9.7 Dehumidifiers or Drsers.
5.9.7.1 Any drying agent used shall 1w approved for itse with oxYgen.
5.9.7.2 Construction Material.
5.9.7.2.1 The container housing the drving agent shall he constructed of an approved material and shall 1w strong enough to withstand the pressure to which it could be subjected.
5.9.7.2.2 If steel is used, it shall be protected from corrosion,
5.9.7.3 Gasket materials used shall be approved fur use with oxYgen.
5.9.8 Hose.
5.9.8.1 1 lose shall 1w approved for use with oxvgeiz.
5.9.8.2 Hose shall Fw strong enough to withstand an’ pressure to which it might he subjected.
5.9.8.3 1 lose oiiIIectiui,s shall 1w secured to present loosen— ing.
5.9.8.4 The otitlet end of the how shall be equipped with a sliiiofT salve.
5.9.8.5 The valve outlet shall iw attachable to the system fill receptacle and shall be secured to prevent loosening.
5.9.9 Precautions.
5.9.9.1 Oil, grease. or other such combustible material shall not be permitted to come iii contact with the equipment.
5.9.9.2 Tliread-sealiiig coinpotiiid_s. when used, shall 1w approved br use with oxygen.
5.9.9.3 All pails of the equipment shall be cleaned of oil or grease befoir l)rueg asscinblrsl.
5.9.9.4 The transport unit manifold outlet valve immediateh upstl’eam of the regulator shall be in the closed position before the cylinder valves are opened.
5.9.9.5 Oxygen salves shall be opened slowly to avoid rapid pressure rise.
5.9.9.6 Afier ihc cylinder salves on the transportation unit arc opened, the manifold outlet salve shall not be opened for (30 seconds to allow heat to dissipate.
5.9.9.7 Where the regulator is not the self-relieving type, the regulator shall 1w relieved of pressure before the manifold outlet salve to the regulator is opened.
5.9.9.8 Before disconnecting, the salve at the end of the fill hose shall be closed to asoid whipping.
NFPA 410 pdf download.