Abstract: A device and a method of remotely locating &agr; particle sources. In the method of remotely locating sources of &agr; particles in an environment, a scintillating gas is used that may contain nitrogen and fills the environment (10, 30), the scintillating gas is used to convert the &agr; particles emitted by the sources (14) into ultraviolet radiation, and an image of the ultraviolet radiation is formed on a photosensitive surface (20). This image can be displayed on film or on a video screen and may be superimposed on the visible image of the observed field. The device and method may be applicable to radioprotection and to the detection of the presence of radioactive materials and sources of radiation leaks.

Abstract: The invention makes it possible to measure the degree of radioactive radiation emitted by large pieces. It includes two large gamma ray detectors (12A, 12B) placed opposite each other and whose spacing is adjustable. They are completed by a photoelectron multiplier (14A, 14B). The piece (2) to be measured is suspended so as to be brought between the two detectors (12A, 12B). The positioning of these detectors is obtained with the aid of a computer and a system (22) for recognizing the shape of the piece (2) functioning with the aid of optical clip-on lenses. The fact that the two detectors are position-adjustable makes it possible to take account of the shape of the piece to be measured. An application is the recovery of materials originating from nuclear installations with the view to re-using the materials.