Increasing Vehicular population and deteriorating quality of air is the by-product of rapid growth of population and haphazard urbanization in India. The urban population in India has increased significantly from 62 million in 1951 to 285 million in 2001 and is estimated to grow to 540 million by the year 2021. In terms of percentage of total population, the urban population has gone up from 17% in 1951 to 29% in 2001 and is expected to increase up to around 37% by the year 2021. About 55 million vehicles were playing on Indian roads in 2001. The annual growth rate of motor vehicle population in India has been about 10% during the decade (1991-2001), It is seen
that two wheelers are growing faster than cars.