dosimetry for still other participants did not cover the entire period of exposure; reconstructed doses will be required in these cases to supplement the doses already recorded. However, while the numbers in table 4 will be adjusted with further research and analysis, the overall results will not change appreciably--the preponderance of doses are expected to remain in the level below 0.5 rem. During Operations UPSHOT-KNOTHOLE (1953), TEAPOT (1955), and PLUMBBOB (1957), all at the Nevada Test Site, about 10,000 military observers and maneuver troops were exposed to neutron radiation while observing nuclear tests from forward locations in the shot areas. Of these, 44 were volunteers positioned closer to ground zero than the other troops. Through reconstruction methods described in chapter 7, neutron doses for the volunteers were determined to be as high as 28 rem, while the highest neutron dose received by regular troops was 1.5 rem for the 500 observers at Shot TESLA, Operation TEAPOT. Neutron doses to all other troops were calculated to be less than 0.5 rem. ‘ At some operations, the circumstances of radiation exposure were such that some participants may have ingested or inhaled radioactive materials. The internal dose from such exposures, determined through a screening methodology in most cases, resulted in a 50-year bone dose commitment of less than 0.15 rem for over 85 percent of the participants. 21