Patent Document ID: 20130208262
Application ID: 13823296
Patent Flag: 0

Claim One:
1. A method for the quantification of the flow from the soil of a fugitive gas from a dispersed source (A) of said gas, comprising the following steps: providing an aircraft (UAV) equipped with a remote detection optical instrument; defining a downwind sampling plane (S) perpendicular to the wind direction, having a width (W) sufficient to contain the projection of the site to be monitored and placed at such a distance from the site as to contain, at the aircraft sampling height, the whole gaseous effluent released by the site; said method being characterized in that it further comprises the steps of flying over said sampling plane (S) for the whole width (W) at a height (H) with said aircraft (UAV) so that said whole fugitive gas remains below said height, carrying out discrete vertical measurements of fugitive gas concentration averaged over said height along the whole width (W) of said plane (S) to yield corresponding mean vertical concentration values, detecting mean wind speed values at said discrete vertical measurements of concentration; integrating the product of said mean vertical concentration values and said corresponding mean wind speed values with respect to the surface of the sampling plane (S) to obtain a value of the fugitive gas flow (Q); correcting the obtained value of the fugitive gas flow (Q) by a corrective factor (α) dependent from the vertical gradient of speed and concentration and obtainable by comparing concentration values obtained by direct measurements and values calculated by dispersion models in order to take into account the speed variation with the height.