Context

The Society of Indian Automobile Manufacturers (SIAM) approached the Supreme Court seeking directions for ensuring sale and registration of BS-IV vehicles is allowed till the cut-off date of March 31, 2020.

About

• The Bharat Stage Emission Standards (BSES), introduced in 2000, are emission standards instituted by the government to regulate the output of air pollutants found in petrol and diesel vehicles. 
• BSES are based on European norms for emission from motor vehicles, which are commonly classified as ‘Euro 2’, ‘Euro 3’
• The regulations were first launched in India in 2000 and have seen several revisions in the last two decades.
• The different norms are brought into force in accordance with the timeline and standards set up by the Central Pollution Control Board (CPCB).
• India 2000, which was based on the Euro 1 standards, was replaced with Bharat Stage II (BSII) norms in 2001.
• These were followed by BS3, while the latter was then replaced with BS4 standards. India is now all set to leapfrog to BS6 emission standards, which will roll out on 1 April 2020.
• The sale of BSIV-compliant vehicles will be banned with the introduction of the next level of emission standards.
• The first emission norms for Indian motor vehicles were the idle emission limits that came into effect in 1989.
• These regulations were replaced by mass emission limits for petrol engines in 1991 and diesel engines in 1992.
• By 1995, the use of catalytic converters was made compulsory for all cars that were sold in metros.
• The following tables hows Indian Emission Standards(four wheel):

 

How BS-VI will make difference?

 

• BS VI norms include a wide list of technology modifications, the most significant being making  ‘On-board diagnostics (OBD)’ mandatory for all vehicles.
• Making OBD mandatory is to make sure that the emission control component work at its optimum efficiency at all times.  
• It will help to detect the malfunction with the help of the error codes sent by the malfunctioning component.
• The BS-VI emission norms would come into force from April 1, 2020, across the country. 

So, what’s the difference between BS IV & BS VI:

• Petrol Emission Norms (All figures in g/km)

Emission Norms	CO	HC	NOx	HC+NOx	PM
BS-IV	1.00	0.10	0.08	---	---
BS-VI	1.00	0.10	0.06	---	0.005

 

• Diesel Emission Norms (All figures in g/km)

Emission Norms	CO	HC	NOx	HC+NOx	PM
BS-IV	0.50	----	0.25	0.30	0.025
BS-VI	0.60	----	0.06	0.17	0.005

 

• Carbon Monoxide emissions (CO): CO emissions are more evident in Petrol engines and long-term exposure to CO can prevent oxygen transfer and increase problems such as headaches/nausea. 
• Hydrocarbons (HC): HC is again more prevalent in Petrol engines and even short-term exposure can cause problems such as headaches, vomiting and disorientation.
• Nitrogen Oxide (NOx): NOx emissions which are more prevalent in Diesel engines. Their long-term exposure can cause irritation in the nose and eye and can also damage lung tissue.
• Particulate matter (PM): PM is again more prevalent in a Diesel engine and their long-term exposure can harm the respiratory tract and reduce lung function.
• Sulphur: At present, the sulphur content in BS-IV petrol and diesel is 50 parts per million (ppm). BS VI-grade fuels, however, are to have a sulphur content of 10ppm. The lower the sulphur content in the fuel, the cleaner it burns.

What’s the need to move SC?

• The move was taken after some state governments issued circulars directing that no applications for registration of BS-IV vehicles would be accepted on or after a certain date.
• According to SIAM, the cut-off dates ranges from February 29 to March 25, from state to state, though BS-VI emission compliance is mandated from April 1, 2020.
• These circulars have put the customers, dealers and vehicle manufacturers in severe discomfort, as each of them is racing against time to exhaust the BS-IV stocks which are with the dealers.
• The Supreme Court has directed that no BS-IV vehicle will be sold or registered from April 1.

Significance of the move:

• OBD: OBD will help in monitoring the pollution levels.
• Real Driving Emission (RDE): RDE will be introduced for the first time to measure the emissions in real-world conditions.
• Reduction in emissions: With BS VI norms,Nitrogen oxide emission will come down by 25 percent for the petrol engine and 70 percent for the diesel engine. PM emission will also decrease by 80 percent in diesel engines.
• Regulation of PM:BS VI norms will change the way particulate matter is measured. It will measure PM by number standards instead of mass standards thereby, regulating the fine particulate matter as well. 
• Low Sulphur levels: BS VI norms have less Sulphur than BS IV, which is a significant cause of air pollution in cities.
• Improving the global environment: It will bring much-needed changes in the Indian automobile industry in terms of pollutant emissions and with this, India will come at pat with the United States, European countries and other advanced automotive markets in the world. 

Conclusion:

With the rollout of BSVI fuels across the country, several older vehicles, which would be compliant to BSIV, BSIII, or BSII norms, will have to run on cleaner fuel. The sulphur content in BSVI fuels is much lower than that of BSIV fuels. Hence, improved fuel will only lead to lower pollution. Talking about the BSVI fuel effect on BSIV cars, the latter could require some fine-tuning in the long run, but there is nothing that the car owners should be worried about. Sulphur works as a lubricant for the injectors of diesel engines, so, the low sulphur content might lead to higher wear and tear in the long run. However, the engines can be safely run for lakhs of kilometres without requiring any additional maintenance.