Page 27 - Advances In Productive, Safe, and Responsible Coal Mining

of mining
Percentage surface 9.2 23.9 29.5 43.8

Productivity (tons/miner/year) 962 1164 2294 4221

production tons)

1940–70 US (million 513 562 435 610

data: incidence IR equiv )

productivity fatal Equivalent (Fatal 0.260 0.133 0.171 0.180

and of rate

safety Number fatalities 643 325 260

of 1388
Summary of Number miners 533,267 483,239 189,679 144,480

2.1
Table Year 1940 1950 1960 1970