title: Air quality assessment in Delhi: before and after CNG as fuel.
abstract: A number of policy measures have been activated in India in order to control the levels of air pollutants such as particulate matter, sulphur dioxide (SO(2)) and nitrogen dioxide (NO(2)). Delhi, which is one of the most polluted cities in the world, is also going through the implementation phase of the control policies. Ambient air quality data monitored during 2000 to 2003, at 10 sites in Delhi, were analyzed to assess the impact of implementation of these measures, specifically fuel change in vehicles. This paper presents the impact of policy measures on ambient air quality levels and also the source apportionment. CO and NO(2) concentration levels in ambient air are found to be associated with the mobile sources. The temporal variation of air quality data shows the significant effect of shift to CNG (Compressed Natural Gas) in vehicles.
authors.affiliation: National Environmental Engineering Research Institute, Nehru Marg, Nagpur, India. ashachelani@rediffmail.com
authors.forename: Asha B
authors.initials: AB
authors.lastname: Chelani
authors.forename: Sukumar
authors.initials: S
authors.lastname: Devotta
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution; D002947:Cities; D004784:Environmental Monitoring / Q000706:statistics & numerical data; D005579:Fossil Fuels; D007194:India; D009585:Nitrogen Dioxide / Q000032:analysis; D052638:Particulate Matter; D013458:Sulfur Dioxide / Q000032:analysis; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D005579:Fossil Fuels; D052638:Particulate Matter; D001335:Vehicle Emissions; D013458:Sulfur Dioxide; D009585:Nitrogen Dioxide