Abstract: A device and method are disclosed for measuring heat flux, as is a method for forming a device for such use. Thermopile junctions are formed on a belt-like support so that the heat flux from an article, such as a pipe or process equipment, is sensed while the support is positioned against a surface of the article, and a voltage indicative of the sensed heat flux is generated and coupled to an outlet connector adapted for connection to a voltage readout device. The belt-like support is relatively narrow, flexible, and has one side of a polymer with high infrared emissivity and the other side of a metal foil with low infrared emissivity.