To illustrate a real situation, a test was performed at a North Sea offshore gas platform.

As illustrated in the graphic below real gas was released (through a 3 mm hole at a gas pressure of 55 BAR). On the platform several traditional point detectors and open path detectors were installed in order to detect hydrocarbon gas leaks. The test team carried hand held LEL gas detectors to investigate in which range such a gas leak could be detected.

To their astonishment, the gas cloud was diluted to 0% LEL only 4-5 metres in front of and 1 metre to either side of the leak. But most alarming was that none of the traditional fixed gas detectors on the platform ever detected the gas from the test leak! - the Gassonic ultrasonic gas leak detector detected the same leak instantly up to 19 metres away!