Until the two travel ways are made as required by § 45.1-161.162, not more than twenty miners shall work underground in the mine at one time. No additional development shall be permitted until the connection is made to the second opening. In mines where final pillar removal operations necessitate closing the second opening, not more than twenty miners shall be permitted to work in the mine.
Code 1950, § 45-71; 1954, c. 191; 1966, c. 594, § 45.1-94; 1994, c. 28; 1996, c. 774.