Aspects of the invention provide a system for disinfecting a humidifier containing a volume of water. An enclosure, such as a humidifier, includes a first chamber, a second chamber, a humidifier component, a third chamber, and a control unit. The first chamber contains a volume of water and a portion of the water flows into the second chamber. A first set of ultraviolet radiation sources within the first chamber can be configured to generate UV-A radiation, while a second set of ultraviolet radiation sources within the second chamber can be configured to generate UV-C radiation. In operation, the humidifier component adjacent to the second chamber creates water vapor using the portion of the volume of water within the second chamber. The water vapor flows into a third chamber that contains the water vapor and releases the water vapor into the ambient.