From demographic mortality and disability of, in total, 424965 y from workers in 29 coal or coloured/metal mines in Human province of China during the period 1980-1984, we calculated the length of expected working life (EWL) as well as the life expectancy (EL) of the workers in the different types of mines and between those working on the surface and those working underground. The average life expectancy in the coal mines for those starting work at 15 y was found to be 58.91 y and 49.23 y for surface and underground workers respectively. In the coloured/metal mines they were 60.24 y and 56.55 y respectively. If only the mortality data was taken into account; for the coal mines, the EWL at the age of 15 y of surface workers and underground workers was 48.46 and 45.10 y respectively; whilst in the coloured/metal mines the figures were 48.25 and 45.99 y respectively. If both mortality and morbidity data is used the EWL at the same age and in the same population is for the coal mines 39.42 (surface workers) 25.54 (underground workers) and for the coloured/metal mines 42.05 (surface workers) and 30.02 (underground workers). The main causes of the lowered EWL of the underground workers were industrial accidents and pneumoconiosis which indicates that safety measures need to be increased and working conditions improved to protect underground workers.