"A Radiological Defense (RADEF) Program is essential to minimize effects of radiation hazards in the event of a nuclear attack and to facilitate recovery efforts. RADEF provides: (1) Shelter monitoring to assess and evaluate protection of occupants against radiation. (2) Radiological monitoring for self-protection of personnel engaged in emergency services functions, operation of primary facilities, and in recovery operations. (3) Recovery techniques including decontamination and related countermeasures". (USACE, Planning and Operations Guidelines, Annex B: Emergency Relocation Sites, 1985, p. B-6)