A method for determining the location of a fecal insult, includes: detecting the concentration of at least one gas indicative of feces at a plurality of locations in a defined space; and determining whether said concentration of said gas exceeds a predetermined first threshold value. The method includes: detecting the concentration of hydrogen gas at each of said locations; detecting the concentration of at least one further gas component being indicative of feces in said space; and determining that a fecal insult has occurred in a location where said detected concentration of hydrogen gas exceeds said first threshold value, provided that the detected concentration of said further gas component also exceeds a predetermined second threshold value in said location.