Project 2.1 - Garma Exposure vs Distance - P, Brown OBTFECTIVE . The object was to measure initial and residual gamma radiation using NBS type film badges, quartz fiber dosimeters, and chemical dosimeters, DESCRIPTION AND EXPFRIMTNTAL PROCPDURES Standard film taiges and quartz fiter dosimeters were distributed at varicus positions throughout Pikini Atoll] anj on the ship stationed in the predicted fallout area. Some baires were exposed without interruption, while others were exposed in sequence or shielded from the fallout by dropping mechanisms activated after blast arrival. RESULTS . Since all of the results are total expcsures it was necessary to estimate the amount of residual in crier to evaluate the initial gamma exposure. The estimates were based on known residual exposures at Similar stations just outside the range of initial exposure and on rclative recovery times and recovery rates, The estimated residual contamination was 150 roentgens for the land stations and 15 roentzens for the reef stations from Airukiiji through Pniirikku. Since individ- val residual exposure values may fluctuate, the value of initial data from a few of the stations is questionable. all of the data should be of value. However, a curve based on Table 2.1-1 gives the initial results. CONCIUSTONS The initial gamma exposure results are in reasonable agreement - 29 ~ Qs with predictions contained in TM 23-200,

Select target paragraph3