Section 164(4) in The Coal Mines Regulations, 2011
(4)In every gassy seam of the second or third degree,-(a)two or more auxiliary fans shall not be installed in the same ventilating district or split, except with the permission in writing of the Regional Inspector and subject to such conditions as he may specify therein;(b)the application made under clause (a) for any such installation shall be accompanied by a plan showing the general system of ventilation, the quantity of air flowing in the split and the proposed position of the fans; and(c)the Regional Inspector may at any time, by an order in writing require that the Use of any auxiliary fan shall be discontinued.
