Electromagnetic Detection (EM)

EM utilizes several different methods to locate utilities know as passive, conductive and inductive. Our experienced EM Technicians evaluate each project while on site to determine the most effective methods to use.

EM works by detecting the electromagnetic radio frequency emitted by conductive materials. The radio frequency is conducted or induced onto the utility by a transmitter. This signal is carried by the conductor along its length and is detected above ground with the radio frequency antenna. Often, buried electrical and telephone utilities radiate their own electromagnetic field and can be readily detected using the radio frequency (RF) receiver without inducing a current. By detecting the maximum signal strength at several locations, the surface trace of an underground utility can be determined.