Limited data was available regarding the effectiveness of commercially available and commonly used OSHA Level B suits to protect against CW agents. As a result, the U.S. Army Soldier and Biological Command (SBCCOM) created a program to test some Level B suit designs, using CW agents and test procedures developed for an assessment of military-issue CW protective equipment. Level B protection consists of chemical-resistant clothing (overalls and long-sleeved jacket; hooded one or two piece chemical splash suit; disposable chemical-resistant one-piece suit), inner and outer gloves, chemical-resistant safety boots, and hard-hat with pressure-demand full-face piece SCBA or pressure-demand supplied-air respirator with escape SCBA. Level B, rather than Level A, protection is used when a high level of respiratory protection is required but less skin protection is needed. Swatches of material from each suit design were tested for resistance to permeation for Sarin (GB) and Mustard (HD). A calculation was then made concerning the estimated time it would take it to permeate the suit with enough agent to result in physiological effects in a person wearing the suit. Each suit was also tested for its protection factor in an aerosol environment (the researchers’ aerosolized corn oil, which may be representative of a chemical or biological agent). Protection factor was defined as the ratio between the challenge concentration outside the suit and the measured concentration inside the suit. The results showed that the OSHA Level B suits tested could protect wearers from liquid CW agents but only provide minimal protection from a vapor or aerosol threat. Thus, the OSHA Level B material does provide limited skin protection, but the suit itself provides little or no skin protection. As a consequence, these OSHA Level B suits were not recommended for use where either vapor or aerosolized agents may be in the environment. 3 Tables