A circular area (less zones I and II) determined by using minimum safe distance III as the radius and the desired ground zero as the center in which all personnel require minimum protection. Minimum protection denotes that armed forces personnel are prone on open ground with all skin areas covered and with an overall thermal protection at least equal to that provided by a two-layer uniform.
ZONE III (NUCLEAR)
Meaning of ZONE III (NUCLEAR) in English
DOD English dictionary of military terms. Английский словарь военных терминов DOD. 2012