With direct coupling, an RF signal is applied to a cable or pipe where there is access to a contact point. With no access to the utility, the indirect mode is used. A transmitter is placed or walked along the ground surface above the conductor and the signal is induced through earth onto the pipe or cable. For non-conductive pipes and conduits, a plumber's snake can be inserted into the line and a signal induced along its length. Our utility locators, without exception, are all geophysicists and geologists with a strong understanding of geophysical principles and how they are effectively applied to utility location.
Utility location is an exacting science.
No single instrument can detect all types of underground utilities. Field sketches are made and later digitized using our CAD facilities, showing all detected underground utilities as they relate to permanent above ground facilities. A utilities mark-out prior to excavating or drilling should be the rule, not the exception.