Abstract: A heat exchange humidifier for generation of steam-to-steam or fluid-to-steam humidity may include at least one steam tube in a heat exchanger array which may be coated with a non-stick surface such as tetrafluoroethylene (TEFLON.RTM.) coating or the like, to prevent the build-up of minerals. The steam tubes in the heat exchanger array are in a substantially layered configuration, each layer being offset and below the preceding upper layer, or in helical configuration. This organization of the tubes in the heat exchanger array maximizes convection currents in a fluid surrounding the steam tubes to minimize dead water films and maximize heat transfer from the steam or fluid inside of the tubes to the surrounding water, resulting in an overall increase in boil-off capacity for adding humidity to the air.