A water filled unitary flexible pouch for use with a heating element for delivering humidified air to a user, comprising a disposable pouch formed from a first and a second flexible polymer sheet sealed to the first flexible polymer sheet, wherein the second flexible polymer sheet comprises a flexible metalized area adapted to contact the heating element. A premeasured amount of distilled water is in the disposable pouch in contact with the flexible metalized area, and forms vaporized water when the flexible metalized area contacts the heating element. An integral inlet port is used to flow continuous pressurized air into the disposable pouch at a titrated pressure ranging from about 4 centimeters of water to about 30 centimeters of water, and an integral outlet port is used to flow vaporized water and pressurized air from the disposable pouch at a pressure up to about 30 centimeters of water.