What is BS6

With the introduction of new and updated automobiles, the environmental pollution level also began to increase. As the pollution grew, the government of India realized the need for automotive emission standards. In 2000, Bharat Stage Emission Standards (BSES) were introduced by Central Pollution Control Board to mandate vehicular emissions. 

Bharat Stage 6 (BS6) 

BS6 is the sixth mandate to control rampant air pollution in India. It is a more restrictive approach implemented by the government, making India equivalent to the US and European emission norms. BS6 full form is Bharat Stage 6, it falls under the Bharat Stage Emission Standards (BSES); these are decrees set to control the air pollutants from an internal combustion engine. BS6 was applicable in India from 1st April 2020. 

Here are some changes that BS6 contains as compared to BS4

• BS6 brings major changes in the fuel, under which BS6-compliant engines require BS6 fuel. Oil companies in India were required to distribute the BS6 grade petrol and diesel.

• Under the BS6 series of changes, the most notable change is the need for all automobiles to have Onboard Diagnostics (OBD).

• Real Driving Emission (RED) is introduced under BS6 standards, which refers to the emission by a vehicle during real-world scenarios against modeled circumstances.

• Additionally, the introductions of Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR) are made for Diesel Engines under Bharat Stage 6

BS6 vs BS4 : How is BS6 Different from BS4?

Bharat Stages are the criterias set for reducing pollution levels, BS6 is the 6 modified version of these criteria known to be the most restrictive version till now. BS4 and BS5 are emission standards set to minimise the quantities of pollutants emitted from a vehicle; BS6 emission requirements are more rigorous than BS4. 

• Under the BS4 norms, an automobile cannot emit NO2 more than 80mg/km; however, under BS6, the emission limit for NO2 is reduced to 60mg/km. 
• BS6 standards have reduced the particulate matter (PM) for petrol vehicles to 4.5mg/km.
• BS6 Norms significantly decreased the pollutant limit by allowing only 80mg/km emission for NOx from diesel vehicles, while BS4 allowed 250mg/km. 
• A drastic reduction in HC+NOx discharge is limited to 170mg/km from 300mg/km under BS6. These norms also reduce PM levels from 25mg/km to 4.5mg/km.
• The fuel under BS6, compared to BS4, contains 5 times less sulphur traced; along with this, the NOx (Nitrogen Oxide) levels are also brought down by 70% for Diesel Engines and 25% for Petrol Engines.

What is a BS6-ready engine?

A BS6 ready engine is a combustion engine that is significantly altered to make it cleaner and malleable with the BS6 emission regulations. BS6 is operated by Selective Catalytic Reduction units. It is a modern emissions device created to regulate emissions. BS6 Engines have adjustments such as better fuel quality and consistent DPF and SCR in diesel cars. 

How Do BS6 (BSVI) Diesel Engines Work?

With the help of a catalyst, Selective Catalytic Reduction (SCR) units produce diatomic nitrogen and water from Nitrogen Oxide. The SCR unit reduces NOx emissions by using AdBlue or diesel exhaust fluid. This fluid contains urea and deionized water. When exhaust fumes interact with AdBlue fluid, urea is transformed into ammonia and carbon dioxide, and ammonia reduces NOx to nitrogen and water vapour, lowering pollution.

In smaller passenger vehicles, AdBlue is stored in a 10-litre tank. As of now, distributors sell AdBlue at a premium level; however, with the rapid growth in sales of BS6 diesel engines, the cost of AdBlue is likely to fall. This is how BS6 Diesel Engines work.

What is the difference between a BS6 Compliant and a BS6 Ready car?

A BS-ready car indicates that the existing non-BS6-compliant car can technically and mechanically get updated to be BS6 compliant with simple changes and adaptations without any engine replacement. The phrase BS6 ready car also refers to the car’s ability to operate on new BS6 fuel without any issues or hassles. A BS6 car, on the other hand, is already built to BS6 standards by the factory.

Best BS6 compliant car in India

Here’s a list of best BS6 compliant cars in India

1. The Mercedes Benz S 350D
2. Jeep Compass Trailhawk
3. Audi Q7
4. Range Rover 
5. Kia Seltos
6. Mahindra XUV700
7. Maruti Brezza

Take Away

The full form of BS6 is Bharat Stage 6, the six modifications of pollution norms under Bharat Stage Emission Standards (BSES) regulated by the Central Pollution Control Board, India. Compared to BS4, BS6 covers notable changes in automobile engine components, which effectively controls air pollution.