Section 152(2) in The Coal Mines Regulations, 2011
(2)Except with the permission of the Chief Inspector in writing and subject to such conditions as he may specify therein and subject to the provisions of sub-regulation (1), every entrance into a mine shall be so designed, constructed, and maintained that its lowest point (which means the point at which a body of rising water on surface can enter the mine) shall be not less than 1.5 metres above the highest flood level at that point.
