Radionuclide identification device

A radionuclide identification device (RID) is a hand-held measurement instrument for the detection and identification of radioactive substances. They are used at national borders, by the police and firefighters to localize radioactive sources and determine the radioactive substances they consist of. A RID measures gamma (photon) radiation and optionally neutron radiation. These devices are sometimes named radio-isotope identifying devices (RIID) or handheld isotope identifiers.