KSPCB's data shows that the average AQI during Diwali was 110, an increase of almost 50% from the AQI of 73.5 observed between October 31 and November 5.
In 2016, it was 278 and in 2015, Mumbai recorded an AQI of 279.
It said the city's air quality has "improved significantly" since Thursday, but the recovery was slow due to low surface wind speed.
Entering the "severe-plus emergency" category, the Air Quality Index was recorded at 574, according to data by the Centre-run SAFAR (System of Air Quality and Weather Forecasting And Research), which experts have attributed exclusively to fireworks. The Central Pollution Control Board's (CPCB) air quality forecast suggests that air quality will continue at "very poor" levels for the next three days across NCR. The AQI index assigns a quality score out of a maximum of 500.
Bandra Kurla Complex was not far behind, with an AQI of 297 (poor).More news: Trump ousts U.S. Attorney General Jeff Sessions, announces interim replacement
It is noted that under the GRAP, stringent actions are implemented based on the air quality of the city. Bhandup recorded the cleanest air in the city, at 101 (moderate).
Delhi: Delhi-wallas, rejoice. Despite the massive focus on the national capital, the city has only the third worst air in north India (and also the most monitoring centres).
-- Dangers of PM 2.5PM2.5 refers to fi ne particulate matter, particles of which are two and a half microns or less in diameter, and can thus penetrate the lung barrier and enter the blood stream.
SAFAR's data showed that PM 2.5 level was more than eight times the permissible limit, while PM 10 was six times the permissible limit. It is expected to rise to 165 µg/m3 on Thursday and then decline to 121 µg/m3 on Friday. Once the PM2.5 level crosses 80 or 100 [micrograms per cubic metre], it has a huge impact on health.
Mohammad Shahid Raza, a young student, said people let off firecrackers until 1 a.m. Thursday in a south Delhi neighborhood where he lived.
This year too, the pollution level spiked to severe-plus emergency levels due to rampant burning of firecrackers leading to the formation of a smoky layer across Delhi. The good news, however, is that this year's Supreme Court-mandated restriction on crackers has seen pollution levels being almost 33% lower than the festivities of 2017.