Question
Can all utility detectors detect depth of utilities?
Answer
In Hong Kong, underground utility detectors are as a rule separated into two categories- electromagnetic detector and ground penetrating radar (GPR).
For electromagnetic detector, it can detect signals emitted by metallic utilities themselves by passive mode. As in active mode, detector has to pick up signals through a transmitter and sonda connected directly to non-metallic utility. Both alignment and depth be able to be found in active mode as only alignment is able to be found in passive mode. Electromagnetic detector available in market can detect utilities up to depth of 3meter.