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Health and Safety Plan 1319 & 1327 South Madison Street, Stockton,CA 432770 El Consultants Pipe Tracing Metal Detector A deep focused metal detector acts as a pipe and cable locator and tracer to detect and trace metallic utilities, utility tracing wires, or warning tapes. In pipe and cable search mode, the instrument is essentially a deep-sensing metal detector that detects any highly electrically conductive material (metals) by creating an electromagnetic field with a transmitting coil. A receiving coil at a fixed separation from the transmitter measures the field strength. As the instrument is swept along the ground surface,subsurface metallic bodies distort the transmitted field.The change in field strength or orientation is sensed by the receiver and triggers an audible alarm and deflection of an analog meter.The instrument can nominally detect a 2-inch metal pipe to a depth of 8 feet and a 10-inch metal pipe to a depth of 14 feet. This technique's effectiveness is limited to metallic objects. It is not useful for plastic,ceramic,or fiberglass utilities. Metal Detector WN Electromagnetic Tracing The electromagnetic technique locates buried materials having a high conductance.This method is commonly used to locate underground storage tanks (UST), buried manhole covers or any subsurface objects with a large ferrous metal content. Alternating electromagnetic waves generated at the surface are induced into the ground during the survey.When thewaves pass through a conducting body,they induce an alternating electrical current in the conductive materials. These currents become the source of secondary magnetic fields,which can be detected at the surface. The strength of the field is directly proportional to the average conductivity of the subsurface materials. Limitations of this technique that can adversely affect the electromagnetic measurements include power lines and metal debris.