text: Project GABRIEL  opened a wide range of questions about formation, transformation, fallout and biological hazards due to bomb debris. GABRIEL supported work in research projects that might apply to the side effects of nuclear war. It was the sole support of the major research effort of Project SUNSHINE, which tested biological damage from radioactive fallout of Sr-90. By 1954 Project GABRIEL included about 70 investigations supported by the Division of Biology and Medicine. At a summer conference that was hosted by the RAND Corporation the estimate of detonations was revised and increased to 25,000 megatons worth of damage. Project Sunshine was led by radiation physicist Willard Libby on July 21, 1953. Libby realized GABRIEL lacked data in other aspects of fallout, examined carbon-14 and developed radiocarbon dating.  The Project GABRIEL report by the AEC was issued in 1954, while the RAND Corporation issued their report on Project SUNSHINE in 1953. Both Project GABRIEL and SUNSHINE played a direct role in the reorganization of the AEC's Division of Biology and Medicine in 1957.