Mack MRU - Page 8

4SafetyInformation
PropertiesofLNG:
LiqueedNaturalGas/Methane(LNG)isacolorless,odorlessgasorliquid.
Atambienttemperatures,theproductisagas,butatcryogenic(super-cooled)
temperaturesitisaliquidorheavygasthatmaytravelalongtheground,riseasit
warmsandvaporizes,andbecometrappedunderanyclosed-inspace.
PropertiesofCNG:
CompressedNaturalGas/Methane(CNG)isacolorless,odorless(sulfur)gas.Itis
compressedat2400to3600poundspersquareinchandstored/usedinspecially
designedcylinders.
NormalMethaneVenting
Themethanefueltanksautomaticallyventtoreleasepressurewhenthevehicleis
parkedforsometime.Duringventingahissingsoundmaybeheard.Thefrequency
anddurationofthisventingwillvarydependingontankpressureandambient
temperature.Itwillcontinuetoventuntilthetruckisoperatedagain,therebydropping
thepressure,oruntilthetank(s)isempty.
PrimaryLNGTankVentPiping
Fromthefactory,theventpipingfromtheprimaryLNGtankventsisattachedtothe
intakestackbydisposableplasticstraps.Thepipingshouldberemovedfromthe
intakestackandplumbedupandoverthebodybythebodyinstallersasshownin
thefollowingillustration.Formoreinformation,seethesectiontitled"LNGTank
PressureV ents"intheOPERATIONsectionofthismanual.
CAUTION
Itisimportanttokeeptheprimary
pressureventfreeofblockagedueto
ice,snowordebris.