Objectives: The objectives of these investigations completed on workplaces in the Hungarian mining industry were to characterize the physiological strain of workers by means of work pulse and to examine the effects of work-related psychological factors. Material and Methods: Continuous heart rate (HR) recording was completed on 71 miners over a total of 794 shifts between 1987 and 1992 in mining plants of the Hungarian mining industry using a 6-channel recorder -Bioport (ZAK, Germany). The work processes were simultaneously documented by video recording along with drawing up the traditional ergonomic workday schedule. All workers passed health evaluation for fitness for work. The effects of different psychological factors (simulated danger, "instrument stress," presence of managers, and effect of prior involvement in accidents as well as different mining technologies and work place illumination) on the work pulse were evaluated. The statistical analysis was completed using SPSS software (version 13.0, SPSS Inc., USA). Results: The work-related physiological strain differed between work places with different mining technologies in groups of 12-18 workers. The work pulse was lowest in bauxite mining (∆HR = 22±8.9 bpm) and highest in drift drilling in dead rock with electric drilling machine (∆HR = 30±6.9 bpm). During sham alarm situation the work pulse was significantly higher than during normal activities with the same physical task (∆HR = 36.7±4.8 bpm vs. 25.8±1.6 bpm, p < 0.001). When work was performed under different psychological stress, the work pulse was consistently higher, while improving the work place illumination decreased the physiological strain appreciably (∆HR (median, 25-75 percentiles) = 23, 20-26 bmp vs. 28, 25-31.3 bpm, p < 0.001). Conclusions: Recording the heart rate during whole-shift work along with the work conditions gives reliable results and helps isolating factors that contribute to increased strain. The results can be used to implement preventive and health promotion measures. Apart from the physiological strain associated with heavy physical work and psychological stress, it is plausible that, due to dust exposure, work in the mines is likely to result in adverse respiratory effects. The coal miner's pneumoconiosis and silicosis are well-known, however, there was no similar effect on the lung function of miners in Australian bauxite mines [15]. The serum aluminum levels were also comparable to normal control subjects [16]. More importantly, however, in a similar geologic area in Hungary, Kovacs found that the thoron to radon concentration ratio was > 0.25, suggesting that there might be an increased health risk [17]. In a systematic screening for cardiovascular limitations by ergometry, we found that the limitations occur roughly twice as often among uranium miners [18] and in coal miners [19] compared to the reference population. This suggests that heavy physical work itself might present increased risk factor for cardiovascular diseases. In underground mining, the heavy ph...