The purpose of this study was to complete an exposure assessment for flock workers lung using data available from a flock manufacturing facility in an effort to explore associations between different exposure metrics and disease. Two different populations of workers from the facility were studied. The first population (study population A) included all workers for whom a detailed work history and symptom data were available (n = 152). The second population (study population B) included all workers in study population A who were evaluated at the MHRI and who have had a HRCT scan (n = 45). The case definition for the study population A, based on the responses to the NIOSH questionnaire or on medical evaluation was: any worker reporting cough and shortness of breath beginning after starting work at this facility and lasting for a period of two months or longer. The case definition for the study population B described above will be any worker with a finding of either diffuse ground glass opacity, micronodularity, or honeycombing on HRCT scan. Six exposure metrics were used in the epidemiologic analysis.- duration of employment in production area, ever/never worked in each job category, ever/never having worked in a job category with peak exposures, duration in job categories with peak exposures, cumulative total dust, and cumulative respirable dust. This study showed that development of chronic respiratory symptoms among workers in a flock manufacturing plant and subsequent development of objectively diagnosed illness were not associated with duration of employment, work in particular job categories, or with a history of the potential for peak exposures. Symptoms of cough and shortness of breath were, however, shown to be associated with work in the production area of the plant and with cumulative respirable dust exposures while controlling for gender. Abnormal CT scans in symptomatic individuals were also associated with cumulative respirable dust exposures while controlling for gender.