Personal Radiation Detectors (PRDs) are designed to detect, and alert a minimally trained wearer when radiation exceeds natural background levels. While a PRD is not an accurate radiation dosimeter, there are models that will calculate and maintain exposure over time. The PRD does not require the attention of the wearer until it alarms. It enables the user to locate the source of the radiation and maintain a safe distance with little or no intrusion or disruption of activities. PRD’s small size and weight considerations are generally what limit functionality when compared to devices that employ larger detectors. PDRs are not typically considered to be a Radio Isotope Identification Device (RIID), but there are a number of small spectroscopic PRD’s devices that combine the capabilities of a PRD with the radionuclide identification capabilities of a RIID into one small package.