The Armstrong HumidiPack^® is a prefabricated steam humidifier system that is ready for insertion in the duct. The HumidiPack^® consists of a separator and header and multiple-tube dispersion assembly when supplied for use with an Armstrong steam-generating humidifier. A steam-supply control valve, strainer, steam trap and header drain traps are added when HumidiPack^® is used on pressurized steam.