i. The latest fuel policy outlines stringent norms to reduce the sulphur and aromatic content in petrol and diesel, emphasizing the upgrading of engines. These standards, known as Bharat stage emission standards (BS), align with Euro norms and have progressed from Bharat Stage II (BS-II) to BS-VI between 2001 and 2017.
ii. The modification of BS emission standards is crucial to curbing the release of air pollutants from internal combustion engines.
iii. In 2001, Bharat Stage II emission norms were introduced for CNG and LPG vehicles. Under Bharat Stage II, sulphur emissions were regulated to 50 ppm in diesel and 150 ppm in petrol, with aromatic hydrocarbons limited to 42% in the respective fuel.
iv. The objective was to bring down sulphur emission to 50 ppm in petrol and diesel, accompanied by reducing aromatic hydrocarbons to 35%. Consequently, the Indian government directly adopted BS-VI in 2018, bypassing BS V. This initiative has led to decreased levels of CO2 and SO2 in Delhi.
v. Implementation of BS emission standards in Indian cities:
a) 4-wheelers: Bharat Stage II – All metro cities
b) 4-wheelers: Bharat Stage III – Nationwide since October 2010
c) 4-wheelers: Bharat Stage IV – 13 megacities (Delhi and NCR, Mumbai, Kolkata, Chennai, Bengaluru, Surat, Kanpur, Agra, Lucknow, Solapur) since April 2010.
d) 2-wheelers: Bharat Stage III – Nationwide since October 2010
e) 3-wheelers: Bharat Stage III – Nationwide since October 2010