[Respiratory tract diseases in coal miners. II. Chronic non-specific respiratory tract diseases in coal miners].

Miners of two coal mines were examined: mine "A"--2094 miners and mine "B"--1846 miners working underground. Both the examined population and work environment were thoroughly described in part I. Medical examinations involved disease history and occupational inquiry on a special questionnaire form, a part of this questionnaire being based on the BMRC questionnaire. In addition, spirometric examinations were conducted, VC, FEV1 was determined, and chest was X-rayed. Average PNChUO rate in both populations under examinations came to 16.5%; in the "A" mine it was significantly higher (19.1%), compared to the "B" mine--(13.5%). Obturative PNChUO constituted, on average, 1.7% of the total PNChUO rate in both mines and occurred more frequently in the "B" mine (2.1%), where work was more mechanized than in the "A" mine (1.3%). The highest PNChUO percentage was found in those working at most dusted work--stands. The PNChUO rate in its obturative form was found to be directly proportional to age and length of employment. No effect of PNChUO on the quality and rate of changes in EKG in those suffering from this disease was found.