Remote laser detection of natural gas leakages from pipelines

A differential absorption lidar based on a tunable TEA CO₂ laser emitting at 42 lines of the 'hot' 01¹1 — 11¹0 band in the range from 10.9 to 11.4 μm is developed for detecting natural gas leakages from oil pipelines by measuring the ethane content in the atmosphere. The ethane detection sensitivity is 0.9 ppm km. The presence of methane does not distort the measurement results. The developed lidar can detect the natural gas leakage from kilometre heights at the flying velocities up to 200 km h^-1 and a probe pulse repetition rate of 5 Hz.