System and method for directional detection of radiation

A method of decontaminating a region, comprising:

• detecting radiation direction using a directional radiation detection system,
• locating a radiation source based on said direction, and
• decontaminating or isolating said radiation source;
• wherein said directional radiation detection system comprises:
• a plurality of scintillating crystals, responsive to the radiation and being arranged three-dimensionally, with voids between adjacent crystals, such that there are crystals that are inner and crystals that are outer within said arrangement;
• and
• a plurality of light sensors coupled to said crystals for receiving optical signals from said crystals and responsively generating electrical signals;
• wherein said detecting said radiation direction comprises receiving an electrical signal separately from each light sensor, and calculating at least a direction of the radiation based on relative intensities of said signals and mutual occultation among different crystals.