In gassy mines, examinations for gas shall be made immediately before firing each blast or group of multiple blasts. Before work is commenced an examination of the face shall be made.
52 P.S. § 70-625
In gassy mines, examinations for gas shall be made immediately before firing each blast or group of multiple blasts. Before work is commenced an examination of the face shall be made.
52 P.S. § 70-625