Castle Bravo
The decision to carry out the Bravo test under the prevailing winds was made by Dr. Alvin C. Graves, the Scientific Director of Operation Castle. Graves had total authority over detonating the weapon, above that of the military commander of Operation Castle. Graves appears in the widely available film of the earlier 1952 test "Ivy Mike", which examines the last-minute fallout decisions. The narrator, the western actor Reed Hadley, is filmed aboard the control ship in that film, showing the final conference. Hadley points out that 20,000 people live in the potential area of the fallout. He asks the control panel scientist if the test can be aborted and is told "yes", but it would ruin all their preparations in setting up timed measuring instruments. In Mike, the fallout correctly landed north of the inhabited area but, in the 1954 Bravo test, there was a large amount of wind shear, and the wind that was blowing north the day before the test steadily veered towards the east.
Alvin C. Graves
Graves became dismissive of the radiation risks from nuclear testing while serving as test director for the Nevada Test Site shots during the 1950s. He announced that the risks from fallout were "concocted in the minds of weak malingerers." As a spokesman for the Nevada Test Site, he spoke in local areas around Nevada assuring the population of no danger from the activities there. As the head of the Los Alamos Laboratory's J (Test) Division, he was the scientific director or deputy director of most of the nuclear tests from 1948 through the 1950s, including the Desert Rock exercises which exposed military personnel to radiation, and the Castle Bravo test that irradiated many native islanders and test personnel. Asked to testify before the Joint Committee on Atomic Energy on the danger of radiation causing cancer, Graves replied: