The Maharashtra Pollution Control Board on October 21, 2026, revised the Directions for Retrofitting Emission Control Devices on Diesel Generator Sets.
The following has been stated:
• The Board has amended its earlier circular concerning the retrofitting of Retrofit Emission Control Devices (RECDs) on in-use diesel generator (DG) sets in Maharashtra, incorporating directions issued by the Central Pollution Control Board (CPCB) on March 22, 2024. For DG sets with capacity from 61 kW to 800 kW, the prescribed options include installing certified RECDs from approved manufacturers on in-use DG sets older than five years, up to their useful life of 15 years from manufacture or 50,000 operating hours, whichever is earlier; adopting dual-fuel systems for eligible in-use DG sets below 800 kW; shifting to generator sets complying with emission norms under GSR 804(E) dated November 3, 2022; installing new gas-based generators; or retrofitting existing DG sets to operate on a diesel-gas mixture.
• For DG sets of 800 kW and above, suitable Air Pollution Control Devices (APCDs) shall be adopted, subject to compliance with the emission standards under GSR 489(E) dated July 9, 2002, applicable to DG sets exceeding 800 kW. Alternatively, for diesel generating engines exceeding 800 kW (1,000 KVA), RECDs shall be tested by CPCB-approved laboratories under the ISO 8175-5 Mode D2 cycle for the equivalent KVA rating and demonstrate reductions of more than 70% in particulate matter, carbon monoxide, and hydrocarbons.
• The specified equivalent-engine criteria shall also be met. Shifting to new gas-based generators or retrofitting existing sets to operate on a diesel-gas mixture are additional alternatives. All other conditions of the earlier MPCB circular remain unchanged except as modified. Industries, establishments, projects, buildings, utilities, airports, data centres, railway stations and other locations operating DG sets of capacities up to or above 800 kW shall comply with the prescribed measures within 90 days from the date of issuance of the circular.
• Failure to comply with RECD requirements may result in forfeiture of the bank guarantee stipulated in the relevant Consent. MPCB Regional Offices are directed to communicate the requirements to stakeholders and ensure timely compliance.
