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 The Radiological Safety Technical Service Units were composed of instrument repair personnel, photometrists, and analysts. The instrument repair personnel maintained, repaired, and calibrated all instruments used by the radsafe section. They supplied monitoring equipment to all aircraft operating in the test area that did not carry monitors, and they trained pilots in use of that equipment. The photometrists (dosimetry technicians) calibrated film dosimetry badges, prepared casualty and personnel badges, processed film from badges that had been worn, calculated exposure from film data, and recorded the results. Analysts collected and analyzed samples of water, soil, and marine life for radioactivity (Reference B.0.1, p. E-II-6; Reference B.0.4).

PERSONNEL PROTECTION

Tolerance Exposure

The Operation Plan set the maximum allowable dose or tolerance for exposure over a long period at 0.1 roentgen (R) per 24 hours (Reference B.0.1, p. E-I-3). The National Bureau of Standards had established that limit in 1934, and it was used in manufacturing plants in the United States (Reference B.0.8). The Chief of the Radsafe Section stated that this dosage was based on 2 to 2-1/2 years of experiments with dogs, mice, and fruit flies, and on experience with a workforce of 8,000 people (Reference B.0.9). The Operation Plan also stated that an individual was not to have a total exposure of over 50 or 60 R in 2 weeks. If an individual received 10 R in 1 day or 60 R in 2 weeks he was to be withdrawn from active participation in the operation (Reference B.0.1, p. E-I-3). Such action was never required. The highest accumulated recorded exposure for the operation was 3.72 R, which was received by an Army assistant radsafe monitor badged for 6 days. The highest number of badges issued to a single individual was 19. He was also a radsafe monitor and his cumulative exposure was 2.48 R.

Provision was made for special situations (Reference B.0.1, p. E-II-9) that might:


 * ...permit the assuming of a calculated risk in order to let certain key personnel enter a hazardous area to make highly desirable observations when the total amount of radiation to be received is less than 10 roentgen units. This may be permitted only on direct instructions from Radiological Safety Control. Details of the situation and clearance therefore will be carefully logged by the accompanying monitor and at Radiological Safety Control.

There is no record that this special provision was involved during the operation.

On 5 August the Medico-Legal Board recommended that three monitors refrain from monitoring for 1 or 2 days because of badge readings in excess of 0.1 R (Reference C.0.10). Later, monitors who exceeded the tolerance were removed from work on USS Salt Lake City (CA-25) (Reference C.0.11).

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