SC on BS-III Vehicle ban: What is BS 3 and BS 4? All you need to know about emission norms standards

New Delhi : The Supreme Court Of India Has Banned The Sale And Registration Of New BS-III Vehicles In India From April 1, 2017. Most developed countries have stringent factory checks in place to ensure vehicles coming out meet the tight norms already in place. 

What are Bharat stage emission rule?

Bharat stage emission standards are emission standards instituted by the Government of India to regulate the output of air pollutants from internal combustion engine equipment, including motor vehicles. The standards and the timeline for implementation are set by the Central Pollution Control Board under the Ministry of Environment & Forests and climate change.

The Bharat Stage norms are based on European regulations. In 13 major cities, Bharat Stage IV emission standards were put in place in April 2010. BS-IV norms were supposed to come into effect nationwide from April 2017.

Overview of the emission norms in India

1991 – Idle CO Limits for Petrol Vehicles and Free Acceleration Smoke for Diesel Vehicles, Mass Emission Norms for Petrol Vehicles.

1992 – Mass Emission Norms for Diesel Vehicles.

1996 – Revision of Mass Emission Norms for Petrol and Diesel Vehicles, mandatory fitment of Catalytic Converter for Cars in Metros on Unleaded Petrol.

1998 – Cold Start Norms Introduced.

2000 – India 2000 (Equivalent to Euro I) Norms, Modified IDC (Indian Driving Cycle), Bharat Stage II Norms for Delhi.

2001 – Bharat Stage II (Equivalent to Euro II) Norms for All Metros, Emission Norms for CNG & LPG Vehicles.

2003 – Bharat Stage II (Equivalent to Euro II) Norms for 13 major cities.

2005 – From 1 April Bharat Stage III (Equivalent to Euro III) Norms for 13 major cities.

2010 – Bharat Stage III Emission Norms for 2-wheelers, 3-wheelers and 4-wheelers for entire country whereas Bharat Stage – IV (Equivalent to Euro IV) for 13 major cities for only 4-wheelers. Bharat Stage IV also has norms on OBD (similar to Euro III but diluted)

2020 – Proposed date for country to adopt Bharat Stage VI norms for cars, skipping Bharat Stage V

Difference between BS-IV and BS-VI standards

The BS norms have been similar to Euro norms till now, and with norms after BS-IV not defined yet, we compare the existing BS-III and BS-IV norms in India with the Euro 6 norms on which India's emission norms have been set.

1. Petrol Emission Norms (All figures in g/km)

Emission Norm    CO          HC         NOx    HC+NOx   PM

BS-III                   2.30      0.20         0.15      ---          ---

BS-IV                   1.00      0.10         0.08       ---          ---

Euro 6                  1.00      0.10         0.06      ---        0.005

2. Diesel Emission Norms (All figures in g/km)  

Emission Norm    CO        HC       NOx    HC+NOx   PM

BS-III                   0.64       ---      0.50      0.56        0.05 

BS-IV                    0.50       ---      0.25      0.30       0.025

Euro 6                   0.50       ---      0.06      0.17       0.005

Source - Indian Emissions Regulations/ARAI 

What are 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).

What are BS 4 Emission norms 

BS-IV norms have also been in practice since 2010 in 13 major cities. Now, it will be followed nationwide. BS-4 (Bharat Stage 4) Emission norms are a set of norms and rules which set the guidelines for the permissible emission levels. The Emission norms are are classified under category of vehicles i.e. Commercial Vehicle, Passenger Vehicle, Light Duty , Heavy Duty Vehicle etc. & further classified under Diesel & Petrol (Gasoline) engine.