In many regions of the world, older, high-emitting vehicles account for a small percentage of the overall vehicle fleet but a disproportionately large share of total emissions. It is estimated that these vehicles may be responsible for more than 50% of particulate matter (PM) and black carbon (BC) emissions by 2020 (Yan et al., 2011).

A comprehensive survey, setting India’s policy options in the context of international experience and assessing technology costs versus health and economic benefits under several scenarios.

Compliance and enforcement programs aim to ensure that, even after a period of use, vehicle emissions of criteria pollutants (primarily particulates, nitrogen oxides, hydrocarbons, and carbon monoxide) do not exceed the original certification standards.

Investing in ultra-low-sulfur fuel (ULSF, fuels with less than 10 ppm sulfur content) and clean vehicle technologies in India will not come without costs. But the benefits of these investments, in terms of reduced healthcare costs and higher productivity, far outweigh the costs. This paper discusses these issues in detail.

In short, India stands to gain much more by implementing lower sulphur fuels in tandem with other vehicular emission control measures. In particular, these benefits will stem from adopting a “one country, one fuel, one regulation” policy and reducing fuel sulphur levels to be on par with international best practices.

There are currently around 90 cities that India's Central Pollution Control Board (CPCB) identified as critically polluted. Particulate matter (PM), especially fine particulate matter (PM2.5), dominates the concern. Other air pollutants such as NO2, ozone (O3), and air toxics are also problematic.