During the course of improvement in design of nuclear devices, several accidents have occurred involving irradiation of personnel with radioactive materials resulting from experimental detonations. Knowlton and associates1 described burns on the hands of four persons who were handling fission-product material. Beta lesions and epilation in a large number of Marshall Island people have been described* resulting from fall-out contamination following detonation of a large thermonuclear device in the Pacific in the spring of 1954. This was the same incident in which 23 Japanese fishermen on the "Lucky Dragon" were involved. The lesions in this group were similar to those in the Marshallese.4 There were also a number of American service men who received minor skin lesions in this incident. This report concerns an additional case of an Air Force Officer who developed a skin lesion which was apparently due to contamination with