An industrial hygiene and epidemiologic survey was conducted to determine the extent of exposure to styrene (100425) at 7 fiberglass reinforced plastic boat manufacturing facilities. The properties of styrene are described, and the compounds to which exposure is most likely, are identified. The health effects associated with exposure are discussed, and the routes of exposure are described. The hand lay up and spray up techniques used for contact molding are described, and the materials used in the manufacturing process are identified. The facilities surveyed are described, and survey methods and results are summarized. A substantial variation in exposure to styrene and acetone (67641) was evident in air samples taken throughout the various facilities. Over 20 percent of the personal time weighted average styrene exposures were over the 100 parts per million eight hour standard. Some exposure control measures were adequate, while others were not. Styrene exposure concentrations were highest for job categories involving the hull, deck, small parts, and gel coat operations. There was no trend evident in job categories for acetone exposure. The author recommends the use of local and general ventilation systems, styrene suppressed resins, and work practice guidelines designed to reduce worker exposure concentrations.