Sub:    Approval under Regulation 208 (3) of the Coal Mines Regulations, 2017 for Flameproof DOL Starter rated up to 50 HP, 550/440 V, 3 phase, 50 Hz, size 1, Type No. SF-1 manufactured by M/s. Volga Engineering Co. Pvt. Ltd., Kolkata, in the name of M/s. Prabhu Industrial Udyog Pvt. Ltd, Kolkata, conforming to IS/IEC 60079-1:2014, and IS/IEC 60079-0:2017 for use in below-ground Coal Mines– Renewal thereof.–

Sir,

Please refer to your online application No. E-29021/62510/2025/Electrical (HQ) dated 23.08.2025, on the above subject and CIMFR Test & Assessment Report No. : IN/CIMFR/TR20/797 dated 11.03.2020; No. CIMFR/TC/P/1444 dated 29.01.2013, BIS License No. CM/L- 1855466 and other documents submitted therewith in this regard. 

I, in exercise of powers conferred upon Chief Inspector of Mines (also designated as Director General of Mines Safety) under Regulation 208(3) of the Coal Mines Regulations, 2017, hereby renew the approval (DGMS Approval No. 175 of 1979) granted vide this Directorate's letter No. 335/78/97/EHQ dated 20.01.1979 for a further period of five years, i.e. up to 24.10.2030  for use in belowground Coal Mines.  The conditions mentioned in the original approval and subsequent renewal letters shall be strictly complied with. 

Please note that application for renewal should be made at least three (03) months before the date of expiry of the approval.