India shifts to Bharat Stage VI emission norms (Euro 6) by April 2020.
India shifts to Bharat Stage VI emission norms (Euro 6) by April 2020.Photo: The Quint
  • 1. How Are BS-6 Norms Different From BS-4?
  • 2. What New Tech Is Required For BS-6 Petrol Vehicles?
  • 3. What New Tech Is Required For BS-6 Diesel Vehicles?
  • 4. Can I Run My BS-6 Vehicle With BS-4 Fuel?
  • 5. Can I Run My BS-4 Vehicle with BS-6 Fuel?
BS-VI Tech vs BS-IV: How Different Are The New Emission Norms?

From 1 April 2020, all cars, two-wheelers, three-wheelers, buses and trucks sold in India will have to meet the country’s stringent emission standards: Bharat Stage 6 or BS-VI / BS-6. This is equivalent to Euro 6 emission standards that are already in place in many countries since 2015.

India is leap-frogging from BS-IV emission standards directly to BS-VI to become at par with the developed world in emission norms and battle rising pollution levels in many Indian cities.

That doesn’t mean that by April 2020, all other vehicles will have to be off the road. Vehicles that adhere to BS-III / BS-IV emission standards can continue to ply as long as they have a valid registration (of 15 years). Diesel vehicles in the Delhi-NCR region will be allowed to ply for only 10 years, in a bid to reduce the number of diesel vehicles on the road.

  • 1. How Are BS-6 Norms Different From BS-4?

    Bharat Stage VI emission norms drastically reduce the number of pollutants from vehicular exhaust, compared to the current Bharat Stage IV norms. While the difference in emission levels is not that drastic for petrol engines, it is significant for diesel vehicles.

    The nitrous oxide emission levels (responsible for acid rain) will drop by 25 percent in the case of petrol vehicles and 68 percent for diesel vehicles. Particulate matter emissions, which is the main concern among diesel vehicles in Delhi, will come down by 89 percent for BS-6 diesel vehicles.

    In addition, all vehicles will have real-time monitoring of emissions. All vehicles will have on-board software and OBD (on-board diagnostic) ports to be able to monitor emission levels and give out warnings.

    The changes are not related to just vehicles. Fuel quality will also have to be changed, with low-sulphur petrol and diesel being introduced to meet BS-6 norms. Petrol will have to meet a minimum octane rating of 91 RON (which even BS-4 petrol meets).


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