The estimation of the number of underground coal miners and the annual dose to coal miners in China.

This paper introduces an estimation method for the number of underground coal miners and the annual dose to coal miners in China. It shows that there are about 6 million underground miners at present and the proportion is about 1, 1 and 4 million for national key coal mines, state-owned local coal mines, and township and private-ownership coal mines, respectively. The collective dose is about 1.65 x 10(4) person-Sv y(-1), of which township and private-ownership coal mines contribute about 91%. This paper also points out that the 2000 UNSCEAR report gives the number of miners of coal production and their collective dose, which are underestimated greatly because the report only includes the number of underground miners in national key coal mines, which only accounts for 1/6 of the workers all working under the best ventilation conditions in China.