Centre proposes BS-VII emission norms from April 2029

The Centre has proposed Bharat Stage VII (BS-VII) emission standards for passenger cars from April 1, 2029, expanding pollution controls beyond exhaust emissions to include brake and tyre particles, battery durability and real-world monitoring of fuel consumption and emissions.

The draft amendments to the Central Motor Vehicles Rules, 1989, published in the Gazette on Wednesday by the ministry of road transport and highways, propose a phased rollout in 2029, 2032 and 2035, with progressively tighter emission limits. The draft is open for public consultation, with objections and suggestions to be considered after 30 days of its publication.

While current compliance frameworks evaluate tailpipe emissions through periodic external testing, the new notification mandates internal exhaust-path sensors that measure tailpipe emissions continuously and transmit real-time data directly to the driver’s instrument cluster.

The proposed framework sets limits for carbon monoxide, hydrocarbons, nitrogen oxides and particulate emissions, with both laboratory and real-world driving tests and also regulates the exhaust of ultrafine particulate matter. On-board systems would monitor emissions and flag nitrogen oxide and particulate levels exceeding prescribed limits.

From April 1, 2031, brake-particle limits would be three milligrams per kilometre for pure electric vehicles and seven milligrams for plug-in hybrids, other hybrids, fuel-cell vehicles and internal-combustion engine vehicles. From April 1, 2035, the limit would be three milligrams per kilometre for category M1 vehicles. Particle-number limits would be notified separately.

The draft also requires electric cars and plug-in hybrids to retain at least 75% of initial battery capacity after five years or 100,000 km, and 67% after eight years or 160,000 km, whichever comes first.

Vehicles manufactured from April 1, 2030, would have to provide fuel and electric-energy consumption data through a dedicated port. From April 1, 2032, further data would be accessible through the on-board diagnostics port and anonymously over the air. An environmental vehicle passport would provide information on fuel consumption, battery health and pollutant emissions.

The proposal also covers tyre-abrasion testing, anti-tampering measures and safety requirements for vehicles using compressed natural gas, hydrogen and fuels containing more than 20% ethanol. Some technical limits remain to be notified separately.

“Uniformity has been brought for NOx,” said Anil Chhikara, former deputy transport commissioner of Delhi, adding that the proposal sets a common nitrogen oxide threshold for petrol and diesel vehicles.

Chhikara said advanced sensors and monitoring systems could make roadside repairs difficult, requiring specialised facilities. He also warned that additional hardware and complex calibration could raise vehicle acquisition and logistics costs.