Section 126(4)(d) in The Indian Electricity Rules, 1956
(d)a flame safety lamp shall be provided and maintained in a state of continuous illumination near an apparatus (including portable or transportable apparatus) which remains energised and where the appearance of the flame of such safety lamps indicates the presence of inflammable gas, the supply to all apparatus in the vicinity shall be immediately disconnected and the incident reported forthwith to an official of the mine; [and such apparatus shall be interlocked with the controlling switch in such a manner as to disconnect power supply automatically in the event of percentage of inflammable gas exceeding one and one quarter in that particular district:]