Testimony was presented to aid in the determination of an acceptable level of exposure for vinyl-chloride (75014). The testimony pertained to the areas of epidemiology and surveillance, sampling and analysis, respiratory protection, and exposure levels. Three deaths from angiosarcoma of the liver among polyvinyl-chloride (PVC) workers triggered the organization of a surveillance network to establish the number of deaths from this disease and its possible relationship to occupational exposure to VC and/or PVC. A total of 18 cases among PVC workers has been identified and one for a VC monomer production worker. Average age at death for the PVC workers was 48.5 years. The estimated latent period for this disease was about 20 years. Two additional cases were recently discovered among men employed at factories using PVC to fabricate other products. This tumor has been induced in two animal species exposed to VC down to and including 50 parts per million (ppm). Other health effects from VC exposure may include a disabling liver fibrosis. Results of NIOSH Walk Through Surveys were briefly presented. A compilation of data from air sampling in seven PVC fabrication facilities showed that breathing zone samples ranged from 0.3 to 12ppm with a mean of 3ppm. Estimated time weighted average exposures were about 2ppm. Peak levels of at least 300ppm were noted. Extended exposures at these levels were not considered probable; however, maintenance and repair workers may experience such levels.