Section 235(10) in The Coal Mines Regulations, 2011
(10)Testing of earthing system of the gas transportation pipe lines at a interval of not more than one month shall be done by a competent person authorised for the purpose and record of the same shall be kept in a bound paged book duly signed by the competent person and counter signed by the official in - charge of CBM or CMM or AMM project, colliery engineer and manager.
