Provides the testing and evaluating criteria for Radiation Detection Portal Monitors to detect radioactive materials that could be used for nuclear weapons or radiological dispersal devices, (RDDs). Portal monitors may be used in permanent installations, in temporary installations for short-duration detection needs, or as a transportable system. These systems are used to provide monitoring of people, packages and vehicles to detect illicit radioactive material transportation, or for emergency response to an event that releases radioactive material.