The air quality in Delhi has deteriorated significantly in last few weeks.
Air quality in Delhi plunged to a "severe" level following the Diwali celebration with pollutants rising 20 times in certain areas owing to incessant fireworks and bursting of firecrackers, notwithstanding appeals by authorities.
As per the System of Air Quality and Weather Forecasting and Research (SAFAR), an agency under Ministry of Earth Sciences, the air quality in the capital has turned "severe", a category used to describe the highest level of pollution.
Noise pollution was also high in most of the areas in the city.
Though the Delhi government claimed the pollution level on the Diwali night was less than last year, experts said it was too early to draw a conclusion.
Areas scattered across the megapolis saw alarming levels of pollution at night with Anand Vihar, RK Puram, Mandir Marg and Punjabi Bagh breaching all safety standards in terms of air and noise pollution.
At Anand Vihar, level of PM 10 breached the 2,000 microgram per cubic metre around midnight, which is 20 times more than the safe level of 100. RK Puram recorded the same as 1,333 at around 1 am.
PM (particulate matter) 2.5, finer and more harmful to those susceptible to ailments of the respiratory tract, was at 734 at RK Puram and 619 at Punjabi Bagh around the same time as opposed to the permissible limit of 60.
However, a Delhi government official claimed that initial data from six locations of the city shows that Diwali pollution levels were "lesser than last year, though levels on the higher side than required".
The morning after, Delhi University area was the polluted spot in the city with PM 2.5 and PM 10 being recorded as 446 and 439. SAFAR's IGI Airport station recorded PM 2.5 at 478 and PM 10 at 439.
As per the National Air Quality Index, air in the 'severe' category affects healthy people and seriously impacts those with existing diseases. Residential areas such as Punjabi Bagh, RK Puram also had pollution in the 'severe' category.
As per SAFAR, the pollution levels have been consistently on the higher side this year due to several factors including cooler temperature and paddy burning in neighbouring states.
The meteorological department had cautioned that pollution level during Diwali night would be "severe" due to fireworks and bursting of firecrackers and advised those people with heart and lung diseases to stay indoors.
In all likelihood, air quality during Diwali-2015 is going to be inferior to that of Diwali-2014 owing to cooler temperature and downward shift of inversion layer, SAFAR's Project In-charge, Gurfan Beig, had said.
The PM 2.5 level is expected to be 148 per cent on November 12 and 170 per cent in case of PM 10.
The air quality in Delhi has deteriorated significantly in last few weeks.
Chief Minister Arvind Kejriwal had appealed to people to not burst firecrackers during Diwali so that pollution level in the city does not deteriorate further.