Vehicular fleet has grown many folds during last decade and private vehicles (2 wheelers+ cars) have grown at a faster rate than the public transport systems. In almost all the urban centers of the country, there is high ownership of private vehicles, which in leads to to increased fuel consumption, air pollutant emissions, and congestion levels.
In absence of an effective inspection and maintenance program, older in-use vehicles pollute the most. However, for new vehicles improved emission norms have been introduced in the country.