a “ as —_— exposures exceeding the maximum perrigsap @ precluded. Pre~shot safety planning was accomplished for each event to insure that men, material and facilities would not be subjected to avoidable hazards, Of prime consideration was the threat of radioactive fall-out resulting from the detonations. Prior to each test event a predicted fall-out area was established and only when this area was clear of inhabited locations was the detonation executed. Of the shot delays encountered during Operation FARDTACK, more than ninety per cent were due to undesirable fall-out indications. These fall-out areas were posted in the air Operations Center so that controllers could keep aircraft clear of the danger areas, Pre-shot planning also dealt with damage predictions con- cerning blast, heat and water action, Cn two (2) events at Enivetok and one (1) event at Bikind it was necessary to evacuate liaison type aircraft to preclude blast danage and on one (1) event it was necessary to require complete body covering for all personnel to preclude the possibility of burns. A constant program was pursveda to insure that no one observed detonations with his naked eyes. The possibility of retinal burns constituted a continual threat through the entire operation. Through darnase predication and the precautionary measures dictated by these predictions, no unplanned damage occurred to aircraft and only minor damages were inflicted on base facilities. The most difficult Task Group 7.4 radiological problems of the operation existed in the support of the cloud sampling program. Prior to the operation and based on the scheduled number of detonations planned for HARDTACK, maximum permissable exposures of ten (10) roentgens equivalent man (rem) for cloud sampling and effects aircrews and five (5) rem for all F POPIED/DOE LANL RC eee eeod akeeeae ad me Foe” Tenpioneer,ra