Heath Consultants Remote Methane Leak Detector (RML) - Manual (Page 6)

Overview
The HEATH Remote Methane Leak Detector (RMLD™) is a highly advanced
technology, capable of detecting methane leaks from a remote distance. The RMLD is
the first of a new generation of leak survey instruments that will greatly improve the
productivity and safety of a walking survey.
With the RMLD it is now possible to survey areas that are hard to reach or not easily
accessible. The RMLD does not have to be within the gas plume because it uses laser
technology known as Tunable Diode Laser Absorption Spectroscopy. As the laser passes
through a gas plume, the methane absorbs a portion of the light, which the RMLD then
detects. This technology makes it possible to detect leaks along the sight line without
always having to walk the full length of the service line.
Fig. 1-2
Using laser technology, remote detection allows you to safely survey areas that may be
difficult to reach such as busy roadways, yards with large dogs, fenced off areas, and
other hard to access places.
It is designed to be selective to detecting methane only, and will not false alarm on other
hydrocarbon gases. Gas concentration is calculated by the amount of Infrared light
absorbed by the gas. Since gas is detected along the line of sight of the laser, the
concentration is reported as Parts-per-Million-Meter (ppm-m). Thus, the RMLD
measures the gas cloud concentration times the width of the gas cloud. Based on the
local meteorological conditions, a given amount of gas escaping from the ground will
produce a plume that varies in size and uniformity of concentration levels. The plume,
by nature, is variable and dependent on the soil conditions, temperature, wind, and leak
rate.
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101515-0 RMLD MANUAL REV E