Section 241(1) in The Coal Mines Regulations, 2017
(1)No person shall go into, or work, or be allowed to go into, or work in a mine, other than the precincts of a mine occupied by an office building, canteen, crèche, rest shelter, first aid room or any other building of a similar type, unless he wears a helmet of such type as may be approved by the Chief Inspector by a general or special order in writing:Provided that where the Chief Inspector is of the opinion that due to special circumstances, it is not necessary or reasonably practicable for any person or class of persons going into, or working in a mine to wear a helmet, he may, by a general or special order in writing and subject to such conditions specify therein, exempt such person or class of persons, from the operation of the provisions of this sub-regulation.