Background: Following employee respiratory concerns, we investigated the health effects of rayon flock exposure at a card manufacturing plant. Methods: We conducted a cross-sectional survey including environmental evaluation, standardized questionnaires, spirometry, carbon monoxide diffusing capacity testing, and methacholine challenge testing. Results: From a total of 239 participants, 146 (61%) reported working at least 1 hr per week in areas where flock-coated cards are processed (‘‘flock workers’’) and 47 (20%) reported cleaning equipment with compressed air. These workers had generally higher prevalences of respiratory symptoms. Flock workers and employees with longer tenure at areas where flock-coated cards are processed were more likely to have restrictive impairment of lung function. Although dust and fiber samples were largely below the detection limits, peak exposures to airborne particulate occurred during cleaning with compressed air. Conclusions: Working with rayon flock and cleaning with compressed air were associated with health effects in workers at this plant.