According to the present invention there is provided a neutron dosimeter sensitive in the region of from 1 eV to about 14 MeV which comprises a 10B miniature spectrometer for the region of 1 eV to 30 KeV, a 10B albedo detector for the range of 30 KeV to 1 MeV and a suitable polymer foil selected from polycarbonate foil and a plastic made from a diester of a carbonic acid, such as the product sold under the trade name of CR-39 with a thin proton radiator for the region of 1 MeV to 14 MeV.
