Archive · 5 Sep 2026
IIT-Delhi Retrofit Device Could Cut Old Diesel Pollution 90%
IIT-Delhi-linked technology may help make old diesel trucks and buses less polluting.
The device is attached to an existing vehicle, so the engine does not need to be replaced.
It is expected to cost around ₹4,000–₹5,000.
Tests showed it could reduce tiny particle pollution by up to 90 percent.
It could also lower nitrogen oxide pollution by up to 60 percent.
Older BS-III and BS-IV vehicles may therefore produce emissions closer to newer BS-VI vehicles.
The government plans to create rules before allowing the devices to be widely sold.
Very old vehicles that are no longer useful may still need to be scrapped.
The retrofit emission control device is expected to cost about ₹4,000–₹5,000 per vehicle.
It can reduce particulate matter emissions by up to 90% and nitrogen oxides by 60%.
The device is designed for older BS-III, BS-IV and other diesel vehicles.
Testing reportedly showed retrofitted vehicles could approach Bharat Stage-VI emission levels.
The government is preparing rules under Automotive Industry Standard 228, alongside the existing scrappage policy.
- Who
- The Ministry of Road Transport and Highways, led by Minister Nitin Gadkari, is preparing the proposal for older diesel vehicle owners and fleet operators.
- What
- The government plans to allow retrofit emission control devices to reduce pollution from older diesel vehicles.
- When
- The technology was announced at a Society of Indian Automobile Manufacturers event; Bharat Stage-VI standards took effect in 2020.
- Where
- The proposal concerns diesel vehicles in India and is linked to technology developed through IIT-Delhi.
- Why
- Retrofitting could provide a lower-cost way to reduce emissions from usable older vehicles instead of replacing every vehicle.
- Estimated cost
- Approximately ₹4,000–₹5,000 per vehicle
- Particulate matter reduction
- Up to 90%
- Nitrogen oxide reduction
- Up to 60%
- Compatible vehicles
- BS-III, BS-IV and other older diesel vehicles
- Target emissions
- Levels closer to Bharat Stage-VI vehicles
- Regulatory framework
- Automotive Industry Standard 228
- Policy relationship
- Intended to supplement, not replace, the vehicle scrappage policy