Leak Detection Instruction
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4.2
The Relationship between Propagation Distance and Leak Noise Intensity
Pipes made of different materials have different noise propagation rates. For instance, with
metal pipes, the leak noise fades after traveling a longer distance, while with a polyethylene
pipe, the said distance is considerably shorter. In other words, the leak noise generated by a
metal pipe remains discernible from relatively long distances, but with a polyethylene pipe,
the distance from the leak point should be much shorter so that the leak noise would be
discernible.
4.3
The Relationship between Leak noise and Burial Depth of Leaking Pipe
As may be seen in the images above, the frequency of the leak noise at the point where it is
generated is much higher, but, after going through soil and what fills the space between the
pipe and the surface, the leak noise hugely decreases. Similarly, the intensity or amplitude of
the leak noise is also dampened as the noise makes its way to the surface of the ground from
its source. Therefore, the deeper the pipe is buried underground, the less intense the leak
noise will be and the harder to detect.
