One hundred and twenty-two sheet metal workers in New England were examined over a 10-year interval for loss of pulmonary function and the development of asbestosis or asbestos-related pleural fibrosis. Regression models using the generalized estimating equation (GEE) approach were created to investigate the relationship between exposure and pulmonary function after adjusting for smoking status, age, height, and asbestos-related x-ray changes. A history of shipyard work was a significant contributor to the loss of forced vital capacity (FVC). Among smokers, loss in forced expiratory volume at 1 sec (FEV1) also had a significant relationship to prior shipyard work. There was a borderline significant relationship between percentage predicted FEV1 and cumulative years of asbestos exposure in smokers, as well as years-since-initial-exposure in never-smokers. This study supports previous findings of obstructive airway changes in asbestos-exposed workers and identifies shipboard work as an important predictor of loss in pulmonary function even years after shipyard exposure to asbestos has ceased.