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More Mining Engineering Questions
The thickness of air stopping not less than . . . . . . . . centimeters.
The visible bands in bituminous coal.
In below ground booster or Auxiliary fans is electically driven, installed operated maintained as to prevent open sparking shall not be placed in . . . . . . . . air way.
It is a buff coloured deposit made up of angular fragments of unaltered mineral grains and is characteristically unstratified. The thickness of such deposit may vary from few inches to hundreds of feet
'Phons' is a unit of