Laser wavelengths selection for remote monitoring of propane leaks

Absorption spectra of propane and main atmospheric gases have been analysed in the spectral band around 3.3 µm. It has been shown that a pair of the sensing wavelengths, namely 3.370 µm (that corresponds to the maximum of propane absorption) and 3.570 µm, is appropriate, but this is not the best option. In terms of minimising measurement errors of propane concentration a pair of 3.465 µm and 3.569 µm wavelengths is optimal. The relative concentration errors of propane for this pair of the wavelengths are appreciably less.