SC ban on BS3 vehicles: What is BS-III? All you need to know about BS-III and BS-IV standards

The Supreme Court of India on Wednesday banned the sale and registration of vehicles which are complaint with BS-III emission norms from April 1. 

While taking the decision, the Supreme Court quoted that health of millions are more important than commercial interests of automobile manufacturers.

Here, it becomes important to understand what are BS-III and BS-IV emission standards. Bharat stage emission standards' are emission standards formulated by the Government of India to regulate the output of air pollutants from motor vehicles.

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The Bharat Stage emission standards are European regulations. The BS standards were first launched in India in the year 2000. The vehicles which were manufactured since then are complaint with the BS standards. 

BS-III standards

The banned BS-III emission standards were first introduced in 2005 in NCR and selected 13 cities. Later in 2010, BS-III emission norms were introduced nationwide. Emissions are tested over the India Drive Cycle (IDC).

The emission norms led to phasing out of two stroke engines of two-wheelers. The electronic controls were also introduced keeping in view vehicular emissions. 

The emission norms helped in bringing down the level of pollution significantly whereas there were increase in vehicle cost due to improved technology. 

BS-IV standards

BS-IV norms have also been in practice since 2010 in 13 major cities. Now, it will be followed nationwide.

In order to comply with the BSIV norms, 2- and 3-wheeler manufacturers will have to fit an evaporative emission control unit, which should lower the amount of fuel that is evaporated when the motorcycle is parked.

BS IV standards introduced several new requirements, including tightened NOx+HC emission limits, harmonization of the emission testing cycle and the definition of motorcycle classes with the UNECE Global Technical Regulation 2 (GTR-2). 

Beginning with BS IV standards, emissions are tested over the Worldwide Harmonized Motorcycle Test Cycle (WMTC).

Also read: SC bans BS-III vehicles; sale, registration of automobiles without BS-IV emission norms prohibited from April 1

Also read: Himachal govt makes Bharat Stage-IV emission norms mandatory from April 1