The Society of Indian Automobile Manufacturers (Siam)—the industry body comprising automakers—has suggested introducing these brake and tyre requirements from April 2035, but only after obtaining substantial feedback on tyre and brake suppliers’ readiness. The MoRTH issued the draft BS-7 rules on October 13, wherein it proposed introducing tyre-abrasion requirements and brake-particle emission limits for passenger cars from April 2031.
For brake particles, the proposed “PM10” emission limit in the draft BS-7 norms is 3 milligrams per kilometre (mg/km) for pure electric cars, and 7 mg/km for other specified vehicles, including petrol and diesel ones. From April 1, 2035, the limit would be 3 mg/km for all covered passenger cars. The numerical limits for tyre abrasion are yet to be notified. “PM10” is a category of tiny airborne particles that are 10 micrometres or smaller in diameter.
Siam has suggested implementing both—tyre-abrasion and brake-particle requirements—from April 2035 only. “This request was also put to the MoRTH before the draft was issued,” a source privy to the development stated.
According to an industry executive, one reason for seeking more time is that suppliers need to know exactly how the particles will be measured and what limits their products must meet. They may then need to test existing products, develop new materials or designs, and invest in equipment to demonstrate compliance. Vehicle-makers would also need to test the components as part of the complete vehicle.
Tyre-makers, during the last few days, have said they are technologically prepared for the proposed direction of travel, but have sought clarity on the final limits and testing methods. “That distinction matters. Being able to develop a solution is not the same as knowing exactly what standard a product must pass or how it will be tested…These things take time and this is why we requested for the 2035 deadline,” the executive added.
Siam as well as the MoRTH did not respond to Business Standard’s questions regarding this matter until press time.
Multiple industry executives in India pointed to Europe’s experience with Euro 7 emission norms, where their automakers had made it clear that new requirements needed realistic timelines and technical readiness. When the European Commission proposed the Euro 7 rules in November 2022, it wanted them to apply to new types of cars and vans from July 2025. In February 2023, the European Automobile Manufacturers’ Association (ACEA) stated that this deadline was too short. It asked for at least three years after the complete technical package was finalised, warning that limited supplier and testing capacity could increase costs.
The ACEA also raised specific concerns about pollution from brakes and tyres. It called for brake-particle limits to be introduced only when the testing procedure was fully developed, and said measures to reduce tyre-abrasion particles should be worked out directly with the tyre industry. The association stated that appropriate limits and deadlines depended on having reliable testing methods and enough time for manufacturers and suppliers to prepare.
Subsequent developments in Europe lent weight to the automakers’ concerns about technical readiness. The European Union (EU) adopted the final Euro 7 rules in April 2024, replacing its original July 2025 deadline with a phased rollout. The rules will apply from November 2026 to car models being introduced for the first time, while from November 2027, all new cars sold must comply, including models that were already on sale before the rules came into effect. Tyre-abrasion limits have a separate timeline, with requirements for new car and van tyre models scheduled from July 2028, and all such tyres from July 2030. For brake emissions, the EU adopted detailed testing rules in 2026, after further technical work.
“This experience offers a relevant comparison for India, where automakers want the timeline for brake and tyre emission rules linked to supplier readiness. Suppliers need the final limits and testing methods to assess whether products must be redesigned, what testing is required, and how much investment may be needed,” an executive stated.
When a driver presses the brake pedal, brake pads press against a disc or another braking surface to slow the vehicle. This friction wears down the materials and releases tiny particles into the air. These are known as brake-particle emissions. They are different from exhaust pollution and can occur even when a vehicle has no exhaust, as in a battery-powered electric car.
Tyres also wear down as they roll over the road, releasing tiny particles from the tyre material. This process is known as tyre abrasion. Some of these particles remain on the road or enter the surrounding environment. Tyre emissions also happen in electric cars.
BS-6, introduced in India in 2020, sets limits on air pollutants released by vehicles, including nitrogen oxide, carbon monoxide, and tiny particles from exhausts. BS-7 would expand the framework to cover other sources of pollution, and add checks on how vehicles perform over time.
