Boilermakers are skilled building tradesmen who construct, repair, and dismantle boilers. The present study reports on the evaluation of members of a Michigan boilermaker's union for the presence of signs and symptoms of chronic pulmonary disease. Study variables included standardized evaluations of chest x-ray findings, pulmonary function testing, physical examination, and respiratory symptoms. An overall participation rate of 69% was achieved. A non-participant survey identified no significant differences between participants and non-participants in dyspnea, cough, age, or smoking history. Among participants with greater than 20 years experience in the trade, the mean FVC was 91% of predicted; the FEV, was 86% of predicted; 25% showed at least a 1/0 profusion of interstitial markings on chest x-ray; 30% had bilateral pleural abnormalities; and 52% had audible inspiratory rales on physical examination. Forced vital capacity and forced expiratory volume at one second both decreased with years in the trade. Chest x-ray findings of interstitial fibrosis and pleural plaques were related to ten or more years in the trade, as were respiratory symptoms of pulmonary rales, wheeze, and dyspnea.