Project SHAD (Shipboard Hazard and Defense) was a series of tests conducted by the Department of Defense (DoD) in the 1960's to investigate the effectiveness of shipboard detection of and protection procedures against chemical and biological warfare agents. Within each test there were typically several separate trials involving exposure of vessels with various agents. In some cases, all the trials within a particular test used the same agent, but for some tests, different agents were used in different trials. Agents included chemical warfare agents sarin and VX; biological warfare agents Pasteurella tularensis, Coxiella burnetti, and staph enterotoxin (type B); chemical warfare simulants such as zinc cadmium sulfide; and biological warfare simulants such as Bacillus globigii, Serratia marcesens. Although the tests were originally classified, public and media interest has led DoD to investigate these tests and to declassify and make publicly available relevant information from them, in the form of fact sheets for each test (http://fhp.osd.mil/CBexposures/shad.jsp).

The research examined the current health of participants in the Project SHAD tests and compared their health with that of a comparable group of non-participant veterans. Data on current health status came primarily from a telephone survey, and mortality data were also collected and analyzed. A panel of experts advised the Medical Follow-up Agency investigators in the conduct of this study.