Nearly half the families in and around Delhi have sought medical help for respiratory ailments connected to severe pollution engulfing the capital, according to a new survey.

New Delhi topped global pollution charts on Friday, partly due to revellers defying a ban on firecrackers to celebrate Diwali, the Hindu festival of lights.

The Central Pollution Control Board (CPCB) recorded an overall air quality index of 349 at 9 a.m. Two stations, Bawana and Jahangirpuri, reported "severe" air quality.

Delhi recorded an overall Air Quality Index (AQI) of 349 at 9 a.m. However, at least two weather stations out of the 39 in the city - Bawana and Jahangirpuri - reported 'severe' quality air at 401 and 412,

The Central Pollution Control Board data showed two stations in the national Capital—Jahangirpuri (411) and Bawana (401)—recorded air quality in the severe category

At least a dozen stations recorded an Air Quality Index (AQI) of over 350, falling in the ‘very poor’ air category. The ITI Jahangirpuri area went one notch higher as the zone

The 24-hour average AQI was at 338 (‘very poor’) at 10pm on Sunday, which was marginally lower than Saturday’s 4pm reading of 352.