Notes: From April 1, the petrol pumps in New Delhi started supplying ultra-clean Bharat Stage (BS) VI grade fuel (both petrol and diesel) with an aim to combat the rising levels of air pollution in Delhi-NCR region. With this move, New Delhi has become the India’s first city to switch from BS-IV grade fuels to BS-VI (equivalent to fuel meeting Euro-VI emission norms). The major difference in standards between the existing BS-IV and the new BS-VI auto fuel norms is the presence of sulphur. The newly introduced fuel is estimated to reduce the amount of sulphur released by 80%, from 50 parts per million to 10 ppm. As per the analysts, the emission of Nox (nitrogen oxides) from diesel cars is also expected to reduce by nearly 70% and 25% from cars with petrol engines. Other cities like Noida, Ghaziabad, Gurugram and Faridabad along with 13 major cities, including Mumbai, Chennai, Bengaluru, Hyderabad and Pune, will also switch over to cleaner BS-VI grade fuel from January 2019. However, BS- VI fuel will be rolled out in rest of the country by April 2020.