Trade Analytics




Go Back

India's leapfrog strategy from BS-IV to BS-VI

IBEF, Knowledge Centre

Feb 13, 2020 14:56

The Ministry of Road Transport and Highways (MoRTH) issued a draft notification of Bharat Stage (BS) VI emission standards in 2016 for all major on-road vehicle categories in India. The standards will be applied to light and heavy vehicles, as well as two and three wheeled vehicles. As per the notification, the standards will go into effect for the vehicles manufactured on or after April 1, 2020. The draft proposal specified mass emission standards, type approval requirements, and on-board diagnostic (OBD) system and durability levels for each vehicle category.

The proposed BS-VI standards have wide applicable scope and include substantial changes to existing emission standards - Bharat Stage III and IV. Particularly, tightening of particulate matter (PM) mass emission limits and the introduction of particle number (PN) limits for LDVs and HDVs fitted with gasoline direct injection (GDI) and compression ignition (CI)/diesel engines. This step is likely to lead to almost a universal application of diesel particulate filters (DPF) to control PM emissions from new diesel LDVs and HDVs. This has been quite evident when nominally equivalent PM and PN standards in Europe were adopted.

The real emissions and health benefits from this jump are only possible if these advanced technologies are maintained and properly executed and the requirements for real world emissions tests are made tighter with strong prevention for tampering. This transition will be a challenging task, especially for OEMs, as this will require a significant engine technology changes like improvements in engine combustion and calibration, increased injection and cylinder pressures. These changes need heavy investments and co-ordination through the value chain to ensure a smooth transition.

BS-VI is an outflow standard which will bring truly essential changes in the vehicle industry in terms of pollutant discharge. This outflow standard is becoming effective, India will be at standard with the US, European nations and other progressive economies, globally. BS-VI is in line with Euro-VI norms which have already been adopted by European countries. Currently, India is following BS-IV norms, which were enforced in 2010, in select cities, and across the nation in 2017. The upcoming BS-VI standard includes the huge inventory of innovation changes in the engine, most notable being making on-board diagnostics (OBD) mandatory for all vehicles. OBD unit enables the proper working of the modern emission control device at optimum efficiency throughout the life of vehicle. This will give the large reduction of carbon emission from the vehicles.

Overview of the proposed standards

BS-VI refers to the sixth stage of the Bharat Stage Emission norms that will come into effect from April 1, 2020. The Bharat Stage emission norms implement strict control over emissions from vehicle and are based on the European emission norms. BS I was introduced by Central Pollution Control Board (CPCB), in 2000, under Union Ministry of Environment, Forests, and Climate Change. These were followed by BS II in 2005, BS III in 2010, and BS IV in 2017. The widespread concerns raised over deteriorating air quality in the country have prompted the authorities to skip BS V and move to BS VI.

How are BS VI emission norms different from BS IV?

The major difference between BS IV and BS VI is the quantity of sulphur content in the emissions. While vehicles compliant with BS IV release 50 ppm (parts per million) sulphur, BS VI compliant vehicles will release only 10 ppm sulphur. Further, nitrogen oxide level for BS VI-grade diesel engines and petrol engines will be brought down by 70 per cent and 25 per cent respectively.

The other differences include:

  • Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR) are being introduced with the roll-out of BS-VI norms, which were not a part of BS-IV.
  • Real Driving Emission (RDE) will be introduced in India for the first time with the implementation of Bharat Stage VI emission norms. With RDE, a vehicle’s emission will be measured in real-time conditions.
  • Onboard Diagnostics (OD) System has been made mandatory for all vehicles with the implementation of BS VI.
  • Also, change in the fuel used in vehicles is the major upgrade that is being brought about with the roll-out of BS VI emission norms. A vehicle with BS-VI compliant engine will require BS-VI fuel. If a BS-VI vehicle uses BS-IV-grade fuel, it won’t be able to adhere to the BS-VI emission norms. Similarly, if a BS-IV vehicle uses BS VI-grade fuel, its engine will increase emissions.

Is India prepared?

This nation-wide jump to BS-VI emission norms in 2020 will reduce emissions by as much as 80-90 per cent from new vehicles. A lot of carmakers showcased and launched BS-VI versions of their products in the recently concluded Auto Expo 2020. However, cities will have to upgrade their on-road surveillance, bus and truck operators need sensitisation on the supervision of advance and complex emissions control technologies and efforts which are needed to prevent entry of fraud devices to defeat the stringent operational requirement.

The discussion is needed immediately to fasten up the enthusiasm in cities by 2020 also to inform and influence next round of revision of regulations of BS-VI in 2023 for stronger real-world emissions and in-service compliance requirements for vehicle sold. To give a push to this discussion, Centre for Science and Environment has carried out a quick review of the available information on post Euro-VI reforms which have been introduced in Europe as well as carried out a stakeholder consultation in India to recognise the gaps in current regulations on BS-VI emissions standards and test procedures also to map the blueprint to inform the post-2023 reforms of BS-VI regulations. This stakeholder consultation has tapped into a diverse set of stakeholders with vehicle policy makers, vehicle testing agencies including Automotive Research Association of India and ICAT, automotive industry casing the key vehicles segments, emissions component manufacturer, oil companies, bus corporations, truck operators and international technical bodies like International Council on Clean Transportation.

What makes BS VI a leapfrog strategy?

BS-VI in 2020 is leapfrog not only because India is skipping BS-V standards. It is leapfrog because of several fundamental shifts in approaches to emissions control, monitoring and compliance that are becoming possible for real cuts in emissions. During the next three years, several parameters will be phased in.

  • India will be closed to fuel neutral standards as the difference between petrol and diesel emission will narrow down significantly. Till now, the emissions standards in India have allowed diesel light duty vehicles to emit several times higher nitrogen oxides and particulate matter as compared to the petrol vehicles. These are the pollutants of concern in India. To address this, China has adopted a mix and match approach in which they have taken the best of Euro-VI and California standards to make China-VI fully fuel neutral.
  • Under the new standards, particle numbers from tailpipe will be counted to ensure effective emissions control devices or particulate traps are adopted – to, at least, eliminate 95 per cent of the particles.
  • This is a paradigm shift where vehicles will be tested for real world emissions with portable emissions monitors over the driving pattern of vehicles on the road. This is a more effective way to monitor to check deviation from the certification level of emissions and ensure life-time performance of emissions control systems.
  • It has been projected that due to this move the health benefits would be much higher than the actual costs of the makeover. According to an assessment by the US based International Council on Clean Transportation (ICCT), the enforcement of BS-VI and fuel and emissions standards roadmap will help to avoid 280,000 cumulative avoidable deaths by 2030.

Way forward

Leap to BS-VI emissions standards is an important step forward that needs to be leveraged to maximize emissions and health gains. It can be observed that, although the country is looking to meet the best European standards, Europe stands as the third best standard across the globe. China has gone ahead of Europe by combining the key parameters from the US and Korea to frame its own regulations. China has adopted much tighter testing parameters including tighter RDE tests, limits of particle number linked to RDE, in-service conformity right from the beginning, OBD requirements, on-board NOx tracking, and evaporative standard requirements.

On the back of this global review, it is quite evident that after the introduction of BS-VI vehicles in 2020, significant measures are needed to fully align with the reform packages in Europe related to regulatory and testing requirements of vehicles to meet the real world emissions targets. Therefore, 2023 BS-VI reforms that India is preparing for, needs to be packaged well. It is the need of the hour to align all the factors, responsibilities and pathways in an efficient way to give the reform process a better shape.




Knowledge Centre



IBEF Videos

Indian Edge: Boosting the Services Economy

Oct 17, 2017 16:41
Sangeeta Godbole, Director General, Services Export Promotion Council

Indian Edge: Boosting the Services Economy

Indian Edge: Think Leather, Think India

Indian Edge: Engineering excellence