ABSTRACT The edjectives ef Project 2.1 were: 1) to determine gamma exposures versus Gistance from the point of detonation of various high-yield thermo. maclear G@eviees; ani 2) to draw conclusions from the deta concerning gam exposure eentours for various types ef detonations, and the validity of scaling laws. fhe following types of dosimeters vere used as gamma-radiation detec Photographic, quarts-fiber, chemical, and phosphate~glass. Oorrection fa were applied te compensate for the nonlinear spectral response of the dos ané for stetion shielding. All detectors were calibrated vith co squge Photographic Goaineter film-badge service ané co” calibration facilities provided to other projects as requested. Initial gaame rediation was measured by a series of stations located about 1 to & miles from ground sero. Mechanisms were installed at some o these stations to shield the detectors from residual radiation. An analy of the date indicates that the initial games exposure at 3 miles from Che Sumi, end Navajo was about 1 r. Consequently, initial game radiation Ls Little military significance to exposed personnel as compared to therm! | blast damage resulting from high-yield devices. The curves in this report vary from those published in "4 23-200 (Re ence1), The field Gata fall below predictions at longer ranges, and cross to be greater than predicted at shorter ranges. ‘This difference betveen poedicted anf field data increases with increasing yield. Si. 5 WoW ais reac