Abstract
Testing of the permeation resistance of seven glove and suit materials against commercially available chlorosilanes was performed using the ASTM F739-91 standard test method. In addition to determining the performance of the barriers, the guestion of the validity of selection of protective clothing based on performance against the hydrolysis product (hydrogen chloride) was investigated. The chlorosilanes used as challenge agents were methylhydrogendichlorosilane, dimethyldichlorosilane, trifluoropropylmethyldichlorosilane, trichlorosilane, silicontetrachloride, methyltrichlorosilane, phenyltrichlorosilane, and vinyltrichlorosilane. Protective glove barriers tested were Neoprene® rubber, nitrile rubber, butyl rubber, Viton® polymer, 4H® laminate, Silver Shield® laminate, and latex rubber. Protective clothing barriers were polyvinyl chloride (PVC), Tychem® 7500, CPFIV®, Barricade®, Responder®, Saranex 23P® laminated Tyvek® and Chemrel® Latex performed poorly, with breakthrough noted in 5 minutes or less. Nitrile, Neoprene, and butyl provided some resistance to breakthrough against most of the chlorosilanes but in all cases less than 2 hours. Viton, 4H, and Silver Shield provided in excess of 6 hours of breakthrough resistance with one exception for Viton (over 4 hours against dimethyldichlorosilane). All protective clothing barriers provided at least 8 hours of breakthrough resistance; however, some evidence of degradation was noted for the Saranex-laminated Tyvek, PVC, and Barricade. It was found that the use of the hydrolysis model as a guide for the selection of protective clothing was not valid. Apparently the chlorosilanes more closely mimic the permeation behavior of organic compounds such as carbon tetrachloride (i.e., they are assumed to permeate the barrier as chlorosilanes). This finding is important for others who have considered the use of analogy or other such models in selecting protective clothing.