Delhi’s AQI jumps from 327 to 507 in just12 hours; Mumbai, Kolkata also records poor air quality post Diwali. Check here

Delhi's Air Quality Index (AQI) has worsened, crossing 500 two days after Diwali, reaching the 'Hazardous' level. As of 5 am, the AQI stood at 507, with thick smog covering the city. PM2.5 levels in Delhi-NCR are now over 65 times higher than WHO's safe limit, according to IQAir data.

It is to be noted, AQI figure soared from 327 to 507 within just 12 hours in Delhi. At 9 pm on Saturday, Delhi's AQI was recorded at 327 in most areas.

Very poor air quality was notes in several parts of the city including Alipur, Anand Vihar, Ashok Vihar, Aaya Nagar, Bawana, Burari, Mathura Road, IGI Airport, Dwarka, Jahangirpuri, Mundka, Narela, Patparganj, Rohini, Shadipur, Sonia Vihar, Wazirpur, Mandir Marg, Nehru Nagar, Najafgarh and others

AQI between 0 and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor', and 401 and 500 'severe'.

AQI in Mumbai, Kolkata and other cities

Post Diwali celebrations, the air quality detoriarated in several cities.

The air quality index (AQI) in Kolkata was in the 'poor' category on Saturday following Diwali celebrations, a West Bengal Pollution Control Board (WBPCB) official said.

AQI in terms of PM 2.5 was 288 in Ballygunge, 210 in Jadavpur, 211 in Rabindra Bharati University and 219 in Bidhannagar at 9 am, all classified as 'poor', the official told PTI.

Mumbai recorded AQI at 192 at 10 am on Saturday, according to the global AQI ranking portal 'IQAir' Air quality.

The AQI in several places in Haryana and neighbouring Punjab was recorded in the 'poor' category on Saturday.

According to the Sameer app that provides hourly updates of the national Air Quality Index (AQI) published by the Central Pollution Control Board, the AQI in Chandigarh -- the joint capital of the two states -- was also in the 'poor' category.

The air quality at various places across Himachal Pradesh deteriorated post-Diwali due to bursting of crackers, officials said. This year the average AQI in the state was at 140 (moderate) as compared to 92 last year.