During World War II, both sides produced millions of tons of chemical agents and also made preparations for their use but never employed them in combat. The United States focused its research on the development of protective clothing and skin ointments that would prevent or lessen the severe blistering of mustard agents. 

There were three basic types of experiments that potentially exposed Service members: 

1. Patch or Drop Tests

These were the most common tests and the Chemical Warfare Service used them to evaluate the effectiveness of protective or decontamination ointments in protecting against or treating mustard agent burns. These tests also evaluated how multiple exposures affected an individual’s sensitivity to mustard burns and the effects of physical exercise on these burns. Additionally, a drop of mustard agent was commonly applied to the forearms of basic trainees to impress them with the toxicity of the agent and the need to take appropriate action if exposed. 

2. Chamber Tests

These tests evaluated the effectiveness of protective clothing against mustard agent. 

3. Field Tests

These tests involved the contamination of an area of land with blister agent. Human subjects traversed this terrain to test protective clothing, to monitor the effects of agent on animals in the test site, and to measure agent concentrations in soil and water samples.