humidifier
Device that increases the humidity level in the air of a room.
water level 
tray 
water tank 
Reservoir containing the water to be vaporized in the room.
vaporizing grille 
Perforated panel dispersing the humidified air.
vaporizer 
Device blending air with a fine mist of water before blowing it into the room.
control panel 
Panel containing the controls for operating the humidifier.
air filter 
Device that absorbs dust suspended in the air.