Method of measuring the radiation activity of an object under water by means of collimated gamma-spectrometric underwater measurement

摘要

Method for gamma-spectrometric underwater measurement in which the radioactivity of an object 7 under water is determined. A water-free collimator tube 3 is arranged in the water between the measurement object 7 and a detector 1. The detector is enclosed in a watertight container 2. The container with the detector enclosed in the container is moved in the water and brought into position relative to the object. A protective screen 4 is suitably arranged on the container in order to screen the detector from the activity in the water. The protective screen is preferably exchangeable so as to be capable of being adapted to the activity of the water. The collimator tube is fixed in the protective screen and arranged in an exchangeable manner so as, by varying length and diameter, to adapt the measuring sensitivity of the method to the source strength of the object. IMAGE