Spirometry, full-bodyplethysmography, and inhalation challenge tests are the most frequently used methods for lung function testing. In all, 677 examinations were performed among exposed employees at the Degussa carbon black plant in Kalscheuren/Germany using the above mentioned methods, in order to detect whether there is a measurable impact of carbon black fine dust on pulmonary function, or a higher prevalence of obstructive air-way diseases among the study candidates, and whether fine dust exposure is related to the prevalence of bronchial hyperresposiveness. Within the smokers' group carbon black dust exposure reveals a (minimal) impact upon the lung function of the study subjects. However, the impact of fine dust exposure within that group is less significant than the influence of smoking on pulmonary function. Nevertheless, smokers are displaying significant more frequently signs of obstructive airway diseases compared with nonsmokers. In the smokers' group we found 7.3% of study subjects with signs of obstructive airway diseases compared with 3.9% in the group of nonsmokers. No significant impact of fine dust exposure on lung function could be detected within former- and nonsmokers. The overall percentage of 5.1% is not higher than that of subjects with bronchial hyperresponsiveness in other comparable studies.