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Insights into Editorial: Decoding Emission Norms

Insights into Editorial: Decoding Emission Norms

20 January 2016

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The Centre’s decision to adopt Bharat Stage VI automotive fuels nationwide by April 1, 2020 is a key measure that can, if implemented properly, vastly improve air quality. It also fits in with commitments made at the Paris climate change conference.

  • In November, the government had put in public domain a draft notification for implementation of BS-V and BS-VI emission norms for the automobile sector, covering the four wheeler category.
  • Implementation of the BS V standard was earlier scheduled for 2019. This has now been skipped. BS VI, originally proposed to come in by 2024 has been now advanced to 2020, instead.

What are Bharat norms?

Introduced in the year 2000, the Bharat norms are emission control standards put in place by the government to keep a check on air pollution. Based on the European regulations (Euro norms), these standards set specifications/limits for the release of air pollutants from equipment using internal combustion engines, including vehicles. Typically, the higher the stage, the more stringent the norms.

  • The BS IV norms were introduced in 13 cities apart from the National Capital Region from April 2010. Currently, BS IV fuel is being made available across the country in stages, with the entire nation expected to be covered by April1 2017.

Why is it important to upgrade these norms?

Upgrading to stricter fuel standards helps tackle air pollution. Global automakers are betting big on India as vehicle penetration is still low here, when compared to developed countries. At the same time, cities such as Delhi are already being listed among those with the poorest air quality in the world. The national capital’s recent odd-even car experiment and judicial activism against the registration of big diesel cars shows that governments can no longer afford to relax on this front.

  • With other developing countries such as China having already upgraded to the equivalent of Euro V emission norms a while ago, India has been lagging behind.
  • The experience of countries such as China and Malaysia shows that poor air quality can be bad for business. Therefore, leapfrogging to BS VI can put India ahead in the race for investments too.

BS-VI Norms:

  • The particulate matter emission in BS-V and BS-VI is same for diesel cars though it is 80% less than BS IV.
  • The nitrogen oxide (NOx) level is, however, 55% less in BS-VI over BS-V which in itself is 28% lower than BS IV.
  • The sulphur content in fuel norms for diesel and petrol under both BS-V and -VI standards does not change at 10 ppm, though it is substantially less than 50 mandated for both the fuels under BS-IV.

bharat stages

Why we need these norms?

Major pollutants such as fine particulate matter, sulphur dioxide, nitrogen oxides and carbon monoxide emitted by millions of vehicles on India’s roads are severely affecting the health of people, particularly children whose lungs are immature and hence more vulnerable.

  • Thousands of premature deaths and rising rates of asthma episodes highlight the urgent need to make a radical and complete shift to modern fuels and vehicle technologies.
  • Past national policy of implementation of the BS IV fuel standard also failed primarily because this was not done all over the country and the technical standard also permitted a higher level of sulphur in the fuel.
  • Higher sulphur results in high volumes of fine respirable particulates measuring 2.5 micrometres (PM2.5) being generated in emissions.
  • Since even this obsolete standard was not followed uniformly, many vehicles, especially commercial passenger and freight carriers, have been using lower standard fuel supplied outside big cities. This has rendered their catalytic converters incapable of absorbing pollutants.

Other factors affecting the air quality in the country:

Improved air quality, especially in big urban centres, depends on several factors in an era of fast motorisation.

  • A bloated population of vehicles using fossil fuels has affected travel speeds, worsening pollution levels.
  • Poor civic governance has left roads unpaved and public spaces filled with debris and construction dust, constantly re-circulating particulate matter in the air.
  • Moreover, the monitoring of diesel passenger and commercial vehicles – the biggest contributors to total emissions – for compliance with emissions regulations remains poor.
  • Even, the distortions in urban development policy that facilitate the use of personal motorised vehicles rather than expanding good public transport, walking and cycling, are glaring.

Challenges before the government:

The government could face two key challenges in implementing the decision.

  • First, there are questions about the ability of oil marketing companies to quickly upgrade fuel quality from BS-III and BS-IV standards to BS-VI, which is likely to cost upwards of Rs 40,000 crore.
  • Second, and more challenging, is the task of getting auto firms to make the leap. Automakers have clearly said that going to BS-VI directly would leave them with not enough time to design changes in their vehicles, considering that two critical components — diesel particulate filter and selective catalytic reduction module — would have to be adapted to India’s peculiar conditions, where running speeds are much lower than in Europe or the US.
  • Also, the rollout model of introducing higher grade fuel and vehicles first in the cities has fundamental drawbacks, as was evident in the BS-IV implementation. In the periphery of designated BS-IV cities, BS-III vehicles could be registered; BS-IV vehicles (especially heavy vehicles) were more expensive, and BS-III fuel was cheaper than the BS-IV equivalent. And interstate trucks and buses, the biggest polluters, were forced to stay on with BS-III engines simply because the fuel outside cities did not conform to BS-IV norms.


  • The three parties that are impacted by this decision are automobile, auto-components and petroleum refining companies. According to the government, oil PSUs would need to invest Rs 28,750 crore for the upgrade.
  • The problem for the automobile companies is a bit more complicated. Cars made by European and Japanese companies in India already comply with tougher fuel norms since these are exported to European nations. The problem lies with cheaper cars that cater largely to the domestic market.
  • Also, it will take at least three years of on-road testing with BS-VI fuel before cars can be cleared. That has more to do with Indian weather, traffic and road conditions.

What will change after the new norms kick in?

BS-IV norms are currently followed across 63 Indian cities for petrol and diesel. The BS-IV compliant fuels have sulphur concentration of 50 parts per million (ppm). This will come down to as low as 10 ppm in BS-VI compliant fuels and auto engines. This means a lower level of harmful emissions and reduced incidence of lung diseases.

  • The switch to BS-VI norms will also reduce concentration of carbon monoxide, unburnt hydrocarbons, nitrous oxide and particulate matter from emissions.
  • Finally, the quality upgrade will also result in diesel’s cost of production going up by 63 paise per litre and petrol by Rs 1.40 per litre. The switch will also make petrol vehicles costly by Rs 50,000 and diesel vehicles by Rs 1 lakh.
  • For consumers, this translates into higher retail prices of petrol and diesel.


Rolling out the BS VI standard nationally, skipping BS V, has significant cost implications for fuel producers and the auto-mobile industry, but its positive impact on public health would more than compensate for the investment.