The Dec Scanner detects and evaluates the moisture conditions within roofing systems by non-destructively measuring the electrical impedance. A low frequency electronic signal is generated, transmitted into the material under test via one of the two electrodes incorporated in the rubber electrode mat, and received by the second electrode. The strength of this signal varies in proportion to the amount of moisture in the material under test. The Dec Scanner determines the strength of the current and converts this to a comparative moisture content value. By moving the Dec Scanner across a roof surface in a regular pattern, a continuous reading is obtained, and areas that contain moisture can be readily identified.
Operating procedure:
Moisture detection testing can be done at the time of installation for warranty auditing and quality control, as part of an ongoing maintenance program, or prior to re-roofing or repair of damaged roofs. The Dec Scanner is a durable but lightweight instrument that is easily transported to the roof surface. Having determined a known acceptably dry area, one of three sensitivity ranges is selected, and the Dec Scanner is ready to use. Without causing any damage to the roof surface, the Dec Scanner is moved over the tested area. The Dec Scanner gives continuous moisture condition readings, from which a moisture map of the surface can be drawn up, and leaks traced to their source.