Each steam, foam, carbon dioxide, or clean agent fire fighting apparatus must be marked ``[CARBON DIOXIDE/STEAM/FOAM/CLEAN AGENT--as appropriate] FIRE APPARATUS'' in red letters at least 2 inches high. Branch pipe valves leading to the several compartments must be distinctly marked to indicate the compartments or parts of the vessel to which they lead. [USCG-2006-24797, 77 FR 33874, June 7, 2012]