Schematic for triage and response to a large-scale radiation event developed by the Office of the Assistant Secretary for Preparedness and Response. Triage centers are located in concentric rings around the affected area, providing initial stabilization and decontamination (RTR1-RTR3), more extensive Medical Care (MC), and rapid screening of unexposed or minimally exposed individuals at Assembly Centers (AC). Patients who require further care are evacuated to referral centers in unaffected regions. Complete details will be outlined in a separate publication.