Operation Top Hat was a "local field exercise" conducted by the

United States Army Chemical Corps The Chemical Corps is the branch of the United States Army tasked with defending against chemical, biological, radiological, and nuclear (CBRN) weapons. The Chemical Warfare Service was established on 28 June 1918, combining activities that unti ...

in 1953. The exercise involved the use of Chemical Corps personnel to test biological and chemical warfare decontamination methods. These personnel were deliberately exposed to these contaminants, so as to test decontamination.

Background

In June 1953 the

United States Army The United States Army (USA) is the land warfare, land military branch, service branch of the United States Armed Forces. It is one of the eight Uniformed services of the United States, U.S. uniformed services, and is designated as the Army o ...

formally adopted guidelines regarding the use of human subjects in chemical, biological, or radiological testing and research. The guidelines were adopted per an Army Chief of Staff memo (MM 385) and closely mirrored the

Nuremberg Code The Nuremberg Code (german: Nürnberger Kodex) is a set of ethical research principles for human experimentation created by the court in '' U.S. v Brandt'', one of the Subsequent Nuremberg trials that were held after the Second World War. Tho ...

. These guidelines also required that all research projects involving human subjects receive approval from the Secretary of the Army. The guidelines, however, left a loophole; they did not define what types of experiments and tests required such approval from the secretary, thus encouraging "selective compliance" with the guidelines.Pechura, Constance M. and Rall, David P. ''Veterans at Risk: The Health Effects of Mustard Gas and Lewisite'',
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, U.S. Institute of Medicine: Committee to Survey the Health Effects of Mustard Gas and Lewisite, National Academies Press, 1993, p. 379–80, ().

Tests

Under the guidelines, seven research projects involving chemical weapons and human subjects were submitted by the

Chemical Corps The Chemical Corps is the branch of the United States Army tasked with defending against chemical, biological, radiological, and nuclear (CBRN) weapons. The Chemical Warfare Service was established on 28 June 1918, combining activities that unti ...

for Secretary of the Army approval in August 1953. One project involved

vesicant A blister agent (or vesicant), is a chemical compound that causes severe skin, eye and mucosal pain and irritation. They are named for their ability to cause severe chemical burns, resulting in painful water blisters on the bodies of those affe ...

s, one involved phosgene, and five were experiments which involved

nerve agent Nerve agents, sometimes also called nerve gases, are a class of organic chemicals that disrupt the mechanisms by which nerves transfer messages to organs. The disruption is caused by the blocking of acetylcholinesterase (AChE), an enzyme that ...

s; all seven were approved. Operation Top Hat, however, was not among the projects submitted to the Secretary of the Army for approval. Moreno, Jonathan D. ''Undue Risk: Secret State Experiments on Humans'',
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, Routledge, 2001, pp. 179–80, (). Operation Top Hat was termed a "local field exercise" by the Army and took place from September 15–19, 1953 at the Army Chemical School at

Fort McClellan Fort McClellan, originally Camp McClellan, is a decommissioned United States Army post located adjacent to the city of Anniston, Alabama. During World War II, it was one of the largest U.S. Army installations, training an estimated half-million tr ...

, Alabama. In a 1975 Pentagon Inspector General's report, the military maintained Top Hat was not subject to the guidelines requiring approval because it was a "line of duty" exercise in the Chemical Corps. The experiments used Chemical Corps personnel to test decontamination methods for biological and chemical weapons, including mustard gas and nerve agents. Chemical Corps personnel participating in the tests were not volunteers and were not informed of the tests.

Background

Tests

See also

References

Further reading