Advanced gas leak detection methods in industrial environments are of vital importance as they may translate into a reduction of accidents and economic efficiency. In this paper two approaches for detecting and localizing those leakages remotely, based on the measurement of variables involved when a leak is present, are proposed. Registration and fusion of thermal, depth and visual images as well as gas concentration scanning are the two methods to be compared and integrated in order to predict, with high veracity, whether a gas leak is present.