Before going in-depth into the BS 6 or Bharat Stage 6 norm, let’s start with the basics. The Bharat Stage Emissions Standards (BSES), introduced in the year 2000 are automotive emissions standards mandated by the government of India to keep a check on air pollutants from an internal combustion engine in a vehicle. These standards are set by the Central Pollution Control Board under the Ministry of Environment and Climate change.

Update [October 2018] In a recent ruling, The Supreme Court has ruled that BS4 vehicles will not be sold after March of 2020 when the BS6 norms are put in place.

The BS (Bharat Stage) norms are based on EURO (European) emissions standards. The “India 2000” was rolled out in the year 2000, followed by BS2 and BS3 in 2001 and 2005 respectively. It wasn’t until BS4 (4th stage) (BSIV), that more stringent emissions mandates were enforced. In 2016, the government of India decided to skip BS5 altogether and implement Bharat Stage 6 (BS 6) by the year 2020.

What is BS6 (Bharat Stage 6)?

The Bharat Stage 6 (BSVI) norm is the sixth mandate for vehicular emissions and a much welcome change amidst the rampant air pollution in India. BS 6 is a stricter, more restrictive norm that will give a jumpstart to India’s long battle with air pollution. With the roll-out of the BS 6 norms, India will come at par with the US and European equivalent emissions norms.

Update [April 2019] Maruti Suzuki India Ltd (MSIL) chairman R.C. Bhargava has announced that it will cease production of all diesel cars by April 2020.

How is BS6 different from BS4?

  1. The norm will bring a change in the fuel, as the BS6 compliant engine require BS6 fuel. A BS6 vehicle using BS4 fuel will not adhere to the BS6 norms. Indian oil companies have already started distributing BS6-grade Petrol and Diesel at 391 filling stations in Delhi with plans to make BS6 fuel available in all 13 major metro cities by April 2019.
  2. A vital difference between BS6 and the outgoing BS4 fuel is that the BS6 fuel contains 5 times fewer sulphur traces (10 parts per million) compared to BS4 (50 ppm). NOx (Nitrogen Oxide) level will be brought down by a staggering 70% for Diesel engine and 25% for Petrol Engines.
  3. The BS6 brings along a plethora of changes, most significant being the mandatory OBD (Onboard Diagnostics) for all vehicles.
  4. RDE (Real Driving Emission) will be introduced for the first time that will measure the vehicle’s emission in real-world conditions against simulated conditions.
  5. Introduction of DPF (Diesel Particulate Filter) and SCR (Selective Catalytic Reduction) for Diesel engines.

Must Read: Ethanol | Is It The Future Fuel For India?

What are the challenges with BS6?

While it all sounds good to the consumers, it isn’t all hunky-dory with car manufacturers. With the eventual phase-out of BS4 and introduction of BS6, automakers are pressing round-the-clock to develop BS6 compliant vehicles. In fact, due to non-compliancy, the Diesel engine has taken a massive hit with sales dropping to an all-time low.

Also Read: The Future Of The Diesel Engine

Update Automobile manufacturers need to get rid of their BS4 stock before April as the Supreme Court of India has ruled that no BS4 vehicles will be sold after April 2020.

Billions have been invested in technology, research and development of BS6 fuel compatible engines. Also, with the BS6 upgrade, the cost of manufacturing will shoot up with analysts claiming car prices to soar up by 10%-15%. Luxury carmaker; Mercedes Benz recently introduced their BS 6 ready made-in-India S-Class, way ahead of the deadline.

Can BS4 cars run on BS6 fuel?

Update [April 2019] The Ministry Of Petroleum And Natural Gas has officially announced that it will start rolling BS6 fuel in Delhi NCR (Gurugram, Noida, Ghaziabad, Faridabad) BY April 2019.

Say you have an old car, pre-2020, BS4 compliant vehicle. You might be wondering if this new BS6 fuel will damage your car.

First, let’s get this one straight. If you drive a petrol-powered car, you don’t have to worry about compliance. BS4 petrol and BS6 petrol have very little differences in terms of their chemical composition. Petrol car owners can take a chill pill.

Now, this is not the same with diesel though. BS4 diesel had a much higher Sulphur traces (50 ppm), whereas BS6 diesel contains only 10 ppm of Sulphur which is much forgiving for the environment. But why is Sulphur so important? A diesel engine relies on its injector to ionise the fuel for it to become combustible. Sulphur in diesel cars acts as a lubricant for diesel injector. Using BS6 diesel in a BS4 car will cause the injector to wear out prematurely due to less lubrication (low sulphur). This can also inadvertently increase emissions, due to disruption in the flow pattern of the fuel.

Can BS6 cars run on BS4 fuel?

Update [July 2019] BS6 ready fuel has reached 60% of fuel stations in Delhi NCR. Will increase to 80% by October 2019 as reported by ET Auto.

Let’s flip the case. You have bought a brand new BS6 ready car (perhaps the new 2019 Maruti Suzuki Ertiga BS6) and you fuel your car at a petrol station that only stocks old BS4 fuel. Now you wonder, will BS4 fuel damage my BS6 car?

Again, lets put petrol aside as the chemical composition of both BS4 and BS6 is identically the same. For diesel-powered cars, using BS4 fuel in a BS6 vehicle can cause a host of expensive problems. BS6 diesel engines have very sophisticated electronics and a re-developed exhaust system. With the introduction of DPF (Diesel Particulate Filter) and SCR (Selective Catalytic Reduction), using BS4 diesel with high sulphur content will drastically increase the emission (due to increased sulphur ppm) eventually clogging up the diesel particulate filter. This will also affect the fuel economy in diesel cars.

Popular Read: Electric Car In India | The Clear Picture

Will BS4 Car Be Banned?

Yes, after April 2020. As per the Supreme Court’s verdict on October 2018, sale and purchase of all BS4 vehicles will be banned after April of 2020. The court has even given an ultimatum to car manufacturers to clear their old stock of BS4 vehicles before the deadline. The court has also further made it clear that no extension whatsoever will be given to car companies for old BS4 car stock clearance at any cost.

Update [August 2019] As reported by Finance Minister; Smt Nirmala Saitharaman, BS4 cars purchased till March 2020 will remain operational till the entire period of registration.

Top BS6 ready cars available in India

  1. Maruti Suzuki Ertiga Petrol (1.5-litre K15B Smart Hybrid Petrol)
  2. Mahindra Bolero Power Plus (1.5-litre, Three-Cylinder, Turbo-Diesel)
  3. Kia Seltos (1.5-litre Petrol)
  4. 2019 Hyundai i10 (1.2-litre Petrol and Diesel)
  5. 2019 Mercedes Benz E200e and E200d (2.0-liter Petrol and Diesel)

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Akshat Ajeya

Lead, Content & Creatives at GoMechanic | Automobile Scale Model Collector | DIY guy | Consumer of many foods |

5 Comments

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