Section 115(7) in The Coal Mines Regulations, 2011
(7)Whether the method of extraction is to remove all the coal or as much of the coal as practicable, and to allow the roof to cave in, the operations shall be conducted in such a way as to leave as small an area of un-collapsed roof as possible with due regard to danger from an air blast or weighting on pillars and where possible, suitable means shall be adopted to bring down the goaf at regular intervals.
