on such places. If it appears that fallout may occur which is in multiple roentgens or approaches the conservative off-site guide of 3.9 roentgens in one year, the shot would of course be postponed. Computations allow sizable margins for the errors which necessarily accompany pin-pointed forecasts of wind directions. \ Monitoring Teams in Test Site Area ‘ The off-site monitoring program for Operation Plumbbob was organized to take numerous radiological measurements and to provide close liaison with the citizens of nearby communities. U. 5S. Public Health Service personnel assigned to the Test Organization operate the programs under which the area around the Test Site was divided into 17 zones. One or more technically qualified men have been assigned to live in each zone, Their duties consist not only of normal monitoring activities but also, prior to and during the test series, of learning the communities and families in their zones, getting to know the people and being known by them. Teams are stationed at Las Vegas, Alamo, Caliente, Pioche, Ely, Tonopah, Mercury, Lincoln Mine, Overton, Mesquite, and Bureka (Nevada); St. George, Cedar City and Beaver (Utah); Barstow and Bishop (California); and Kingman (Arizona). In addition to the zone monitors there are eight mobile moni~ tering teams on call to go to any locality to assist if needed or to travel to areas outside the 17 zones, (Twelve fixed-station teams and four mobile teams were utilized during the 1955 Nevada series.) The monitors distribute and collect film badges (used for measurement of radiation dosage), monitor radioactivity on the ground and in the air, collect water and milk samples, and answer public inquiries regarding test fallout. Film Badges Since photographic film is extremely sensitive to radiation, badges containing film have been used extensively in the atomic energy program to measure radiation exposure. During the 1955 series, badges were placed on the interiors and exteriors of buildings in the Test Site area, on trees, fence posts and fences in communities and in the open country. In addition, some of the residents of the nearby area wore badges as a means of aiding the Test Organization in determining the radiation exposure actually experienced by persons in the area. A total of 555 such film badge "stations" were used in the 1955 series. More than 2,000 film badge stations have been established for the 1957 series. In several small communities near the Test Site, all residents except infants and small children have been asked to. ~-~ 54, -