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 that the L&W meter was the most reliable instrument for these measurements because it was energy-independent and insensitive to temperature and humidity changes (Reference C.0.16). Six assault meters, brought out by individual monitors, were used during the operation. They were very rugged and ideal for quick and rough determination of radiation levels from 0.1 to 10 R/24 hours. They proved useful for boarding ships and similar operations (Reference C.0.12, p. 31). The "cutie pie" survey meter was a small instrument capable of measuring beta and gamma radiation up to 100 R/24 hours. Few of these were available for CROSSROADS, but a monitor aboard PGM-32 after BAKER used one and decided it was an excellent portable rate meter (Reference C.0.15, p. 4).

The task force had several instruments for measuring alpha contamination. None, however, proved reliable for field surveys. Photographs of task force activities show the Zeus counting meter, the Zeuto, and the X-323. These three instruments were mentioned in training lectures for monitors (References C.0.17 and B.0.11). One or all may have been the Poppy or Walkie Poppy referred to in radsafe reports after BAKER. The three devices appear to have been small, and each had a carrying handle, but apparently they did not work well outside of USS Haven's (AH-12) air-conditioned laboratories in the hot, humid Bikini climate (Reference C.0.14, p. 4). In addition, the Radsafe Section had five Filter Queen Air Samplers. Basically, these were tank-type vacuum cleaners with an alpha detector and filter paper mounted in the intake tube. Samples collected in the filter papers aboard the target ships had to be returned to Haven where alpha counts were made. Initially, the alpha detectors worked well, but humidity, along with personnel opening the detectors improperly, caused them to fall (Reference C.0.12, pp. 8 and 9).

Personnel Decontamination

Personnel working in radioactive areas sometimes picked up radioactive particles on their bodies and their clothing. Procedures were established to minimize the spread of this contamination and potential internal and external exposure from these radioactive sources. The procedures spelled out for the USS Ajax (AR-6) crew working on repair of Salt Lake City following BAKER were typical and are summarized in the following paragraphs.

Ajax crewmembers slated for work on Salt Lake City left their own compartments wearing only their own shoes. These shoes were removed and left in a compartment adjacent to a designated head (bathroom) where the men donned work clothing. They then left Ajax via a Jacobs ladder into a small boat while carrying canvas gloves and shoe covers. The gloves and shoe covers were put on immediately before boarding the target ship for work and were taken off just before leaving.

Upon return to Ajax, the men boarded by Jacobs ladder and went to the upper deck were they were monitored. They walked only on a deck covering, which presumably was disposed of after use. The men first washed their hands and forearms with hot water and salt-water soap. Then each man washed his own clothing. These were first scrubbed in hot water and salt-water soap and then rinsed in a special hot rinse and rinsed again in plain hot water. The clothes were hung on lines to dry on the upper deck.

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