til yo . . 17) ‘ . 7 G8 a, special one-day training course was arranged to prepare permanently as~ signed Air Force and Army officers at sniwetok to serve as project officers. (couriers). Also during April, tio important radiological safety regulations were published: Group regulation 55-8, “iiadiological Jefense of -niwetok," and 55-17, “Handling of hadioactive Haberials anc -yuipuent.” inese two regu- lations completed the estanlishment of radiological safety procedures be-un in the planning phase. The first of these regulations oresented the procedures for monitoring tniwetox Isiand for dstection of rsaui-logical contamination following test events; the second prescribed the policies for handling radioactive materials and equipuent, particularly tiose maintenance and supply perso.nel working swith contaminated aircraft equiorient,. After the beginning of the nuclear tests, the duclear itesearcn Jfficer was engaged with the routine duties cf pxoviding pre-snot fallout predictions, estimates of expected overpressures, and information relative to the vost-shot rudiological conaitions of airstrips and helicoster oads, as well as tie briefing of military cloud sample couriers. unly one significan. instance of radioactive fallout of Fred (uniwetok) Island was noted during dAacT‘CK, av 0500 hours on L4 may 1.998, The fallout was encountered first snd enued at avoroximately 1500 hours; the desosited meterial aecayed in 4 normal preaicted manner. By 1lY May, the majorportion vf the fallout had Cévayed, ieuving versonnei with an expo sure ranging from 5J) to 1,500 milli-rcentvens, ‘Inic oxposure co..stituted caly 2o00ut oneefiftn of that wnich inuividnals were permitted to receive uuring Gyeration Hamviava, AFWL/ HO