A method for detecting contamination on a moving object moving in a longitudinal direction past a plurality of detectors, wherein a count rate is captured repeatedly by each of the detectors during the movement of the object past the detectors, the captured count rates are weighted in that the count rates of the detector(s) that have a greater separation distance from the object to be measures are weighted lower than the count rates of the detector(s) that have a smaller separation distance from the object to be measured.