According to Central Pollution Control Board data, the city saw an air quality index value of 212 as opposed to 98 on Tuesday.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/rain-abates-delhi%E2%80%99s-air-quality-dips-again
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/indian-express-new-delhi
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/delhi
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-quality-standards
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/indian-meteorological-department-imd
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/central-pollution-control-board-cpcb