This study measured the performance of flashspun polyethylene clothing fabrics and the spunbonded polypropylene composite (spc) fabrics as barriers to chrysotile asbestos fibers. The spc fabric samples were taken from clothing samples obtained from several manufacturers. Ten fabric samples and two controls were concurrently exposed to chrysotile asbestos aerosols. Fibers that penetrated the fabric specimens were captured on sub-micron filters. These fibers were counted and sized from SEM micrographs of random sections of those filters. The aerosol challenge concentration was obtained from filters directly exposed to the asbestos aerosol without an intervening fabric. Penetration percentage was based on the number of fibers that penetrated the fabric versus the number of fibers observed on the uncovered filters. Five different exposures were performed. The penetration of chrysotile fibers through flashspun polyethylene fabrics ranged from 0.24% to 1.0%. In contrast, the penetration of chrysotile fibers through the commercial spc fabrics ranged from 13.4% to 26.8% under the conditions at which these evaluations were conducted. The results demonstrated that the method consistently differentiates performance of protective clothing materials to chrysotile fiber penetration and that flashspun polyethylene fabrics provide greater resistance to asbestos fiber penetration when compared to several different spc fabrics available from several manufacturers.