目標：依據現行勞保局塵肺症殘廢審定標準，探討臺灣煤礦工單純塵肺症肺功能障害的盛行率，並觀察其與坑內工作年數間之關係。方法：本研究自1998年至1999年於礦工內科門診收集284位資料完整，且其胸部X光片依國際勞工組織塵肺症分類法顯現Category 0或Category 1，2或3之單純塵肺症變化的煤礦工，安排其作肺量測定及肺瀰散量檢查。進行性重度肺纖維化患者不包括在內。礦工的工作史由問卷調查而得知。結果：X光等級屬Category 1以上之單純塵肺症患者其FEV1/ FVC異常低下的盛行率為42.6%(69/162)，而FVC及FEV1異常低下的盛行率分別為4.9%(8/162)與10.5% (17/162)。盛行率隨著X光等級與坑內工作年數而提高。肺瀰散量異常的盛行率較FEV1/ FVC者為低。結論：煤礦工單純塵肺症肺功能障害的盛行率視參數的種類而有所不同，肺瀰散量測定可以補充肺量測定之不足。

　　　　　Objectives: To investigate the prevalence of respiratory impairment and its relation to underground exposure among coal workers with simple pneumoconiosis in Taiwan. Methods: This study investigated 284 coal miners, including 122 with X-ray Category 0 and 162 with Categories 1, 2, and 3 (simple pneumoconiosis), from the medical clinics of a hospital. Spirometric measurement and tests for pulmonary diffusing capacity (DLco) were conducted on each subject. Patients with progressive massive fibrosis (PMF) wer e excluded. Occupational histories were obtained from questionnaire survey. Results: The prevalence of an abnormally low FEV1/ FVC (forced expiratory volume in 1s/forced vital capacity) in subjects with simple pneumoconiosis was 42.6%(69/162). For FVC and FEV1, it was 4.9(8/162) and 10.5%(17/62), respectively. The prevalence of abnormally low spirometric values increased with higher X-ray categories and longer underground exposure. The prevalence of an abnormal DLco was also lower than that of FEV1/FVC. Co nclusions: The prevalence of lung functional impairment in simple pneumoconiosis varies with the parameter measured, and DLco determination may be helpful in case of normal spirometric measurement.