Abstract: An electrical heating device is disclosed that is suitable to vaporize air treatment chemicals from an impregnated substrate. The device is provided with a PCT heater held between electrical contacts and a spring that is compressed between the housing of the heating device and one of the electrical contacts to maintain pressure thereon in spite of thermal expansion of the housing, ensuring good electrical contact between the PCT heater and the electrical contacts.

Abstract: Disclosed are methods of determining how effective a product that dispenses an insect repellent or insecticide is in controlling flying insects such as mosquitoes, with no or reduced need for human test subjects. An insect trap or other automated monitoring device is positioned in a test environment and operated in a manner so as to mimic some human attribute (e.g. by dispensing carbon dioxide). Trap/monitoring results in the presence and absence of the operating product are obtained in order to judge relative effectiveness of the active. Further, the real time evaluation of insect populations permits evaluation of time needed to achieve base effectiveness and length of time that effectiveness can be sustained.