An automatic evaluation system for NTA film neutron dosimeters

At CERN, neutron personal monitoring for over 4000 collaborators is perform ed with Kodak NTA films, which have been shown to be the most suitable neut ron dosimeter in the radiation environment around high-energy accelerators. To overcome the lengthy and strenuous manual scanning process with an opti cal microscope, an automatic analysis system has been developed. We report on the successful automatic scanning of NTA films irradiated with Pu-238-Be source neutrons, which results in densely ionised recoil tracks, as well a s on the extension of the method to higher energy neutrons causing sparse a nd fragmentary tracks. The application of the method in routine personal mo nitoring is discussed.