What does 7.5 to 13µm mean related to depth ?

[mckeever1000]

The specifications of a thermal imaging camera state 7.5 to 13µm, what does this mean ??

[dundurn]

It's the range of wavelengths - µm is micrometres - to which the detector is sensitive.

[mckeever1000]

Ah right, so the chances of a thermal imager finding a water leak 2 ft undergorund are virtually impossible ?? I Have a leak in my garden which no one can pinpoint exactly. i was hoping to rent a thermal imager to locate it. Any Advice ??

[Muppit]

Eddie, are you suggesting that wet ground wouldn't be of a different temperature to dry ground?

I work for a scientific consultant / non-destructive testing firm and there are a multitude of uses for thermal imaging and leak detection is one of them. Of course technology solves nothing, it is the skill and ingenuity of it's user that bring value!

Mckeever, depending on the length of pipe and the value of solving the problem there are numerous techniques that could be applied including the following:

Reisitivity survey (dry ground is more resistive than wet ground)
CCTV pipe survey (if you have access to an open end of the pipe and it's big enough to fit a camera down it)
Ground Penetrating Radar (radio signals are dissipated in wet ground)
Low Voltage Leak Detection (two probes, one attached to the pipe,one stuck in the ground with an current passing through - the closer to the leak you get with the probe stuck in the ground the less the resistance will be and the higher the voltage reading)

I won't go on, but I must admit that a thermal imaging camera is probably not the best way to go!