Thick smog blankets Delhi on Deepavali night, AQI at 20 stations ‘severe’

The Air Quality Index, or AQI, is a numerical scale that communicates how polluted the air is and what that pollution may mean for people. Higher numbers indicate worse air quality. An AQI of 371 falls in the ‘very poor’ range under the classification reported in the article, signaling heavily polluted air that can affect health, especially during prolonged exposure.

Delhi’s average AQI for the day settled at 376, compared with 369 on Saturday. At 10 p.m., the overall AQI stood at 371, while 20 monitoring stations were in the ‘severe’ category. Jahangirpuri recorded the highest reading, at 460. Smoke from firecrackers added to existing particulate pollution.

The reading matters because it shows that pollution was not a small, isolated problem. Smog covered neighbourhoods, visibility fell, and residents reported difficulty breathing. The Early Warning System forecast that Delhi’s air could enter the ‘severe’ category from November 9 and remain there for several days.

The pollution was widespread across Delhi, not confined to one neighbourhood. The city had 59 air-quality monitoring stations, and their readings showed a broad deterioration during Deepavali evening. This matters because a citywide pattern points to several pollution sources acting together, rather than one local incident.

At 7 p.m., 19 stations were in the ‘severe’ category. Seven stations were ‘poor’, while the remaining 33 were ‘very poor’. Together, those figures account for all 59 stations. By 10 p.m., the report said 20 stations were in the ‘severe’ category. Jahangirpuri had the highest AQI, recording 460.

The readings matched conditions seen outdoors. A smoky haze blurred streetlights, reduced visibility, and covered roads and residential areas. Delhi’s daily average AQI reached 376, compared with 369 the previous day. The spread of high readings explains why the pollution became a capital-wide concern.

When smoke and fine particles reach these levels, the air becomes visibly hazy and harder to breathe. The article reports that Delhi’s streetlights were blurred, visibility dropped in several areas, and residents reported difficulty breathing. These immediate effects show how pollution can disrupt ordinary movement and outdoor activity, not merely change a monitoring number.

On Deepavali night, smoke from firecrackers hung over roads and residential neighbourhoods. The smell of burnt crackers lingered, while the haze grew denser as celebrations continued. PM2.5 was the capital’s predominant pollutant, and firecracker emissions added more particulate matter to the air. Jahangirpuri recorded an AQI of 460.

Fine particles can irritate the respiratory system; this health explanation is established science, although the article specifically reports breathing difficulty rather than detailing medical outcomes. The forecast indicated that severe air quality could continue for several days, so reduced visibility and breathing discomfort were not necessarily limited to the evening.

‘Green firecrackers’ are firecrackers certified by CSIR-NEERI under the rules described in the article. The source does not explain their technical composition or exactly how their emissions differ from other fireworks. It does make clear that only certified green firecrackers were permitted for sale, while prohibited varieties remained unauthorised.

Delhi’s District Magistrate (East) allowed green firecrackers only on November 7 and 8. They could be burst from 6 a.m. to 7 a.m. and from 8 p.m. to 10 p.m. Sales were restricted to locations designated by the Delhi Police. Bursting firecrackers was also prohibited within 300 metres of hospitals, nursing homes, health centres, old-age homes, educational institutions, and other notified silence zones.

Despite those limits, fireworks were reported in Pitampura, Burari, Mayur Vihar, Bishambardas Marg, and parts of Lutyens’ Delhi. The administration announced joint patrols and enforcement teams, but reports showed that unauthorised use continued during the evening.

Delhi’s smog came from several sources operating at the same time. Air-quality experts attributed the expected deterioration to vehicular emissions, Deepavali celebrations, unfavourable meteorological conditions, and the ongoing peak stubble-burning season in neighbouring states. This combination matters because pollutants from different sources can accumulate over the same city.

Firecrackers added particulate matter directly during the evening, while PM2.5 remained the predominant pollutant. Vehicles continuously released emissions across the capital. At the same time, fires involving crop residue in nearby states were identified as part of the wider pollution picture. The article does not provide separate quantities for each source, so their individual contributions cannot be compared.

The result was a smoky haze, reduced visibility, and an AQI that reached 371 at 10 p.m. The Early Warning System forecast severe air quality from November 9 for several days. That forecast reflected the continuing influence of weather, traffic, regional smoke, and post-celebration pollution.

Weather controls how quickly pollution leaves a city. In general, stronger winds and atmospheric mixing help spread and dilute pollutants, while weak winds or stable layers keep them concentrated near the ground. This is a general explanation of the process; the article identifies unfavourable meteorological conditions but does not specify the exact conditions over Delhi.

Delhi’s pollution sources were active together. Vehicles emitted pollution, firecrackers released smoke during Deepavali, and stubble burning continued in neighbouring states. If the air above the city does not mix effectively, these emissions can remain trapped instead of dispersing. The visible result was a denser haze, blurred streetlights, and reduced visibility.

The Early Warning System forecast that Delhi’s air would likely enter the ‘severe’ category from November 9 and remain there for the following few days. That forecast shows why weather matters: pollution levels depend not only on how much pollution is produced, but also on whether the atmosphere can clear it.

PM2.5 refers to fine particulate matter with a diameter of 2.5 micrometres or less. A micrometre is one-millionth of a metre, so these particles are extremely small. The article identifies PM2.5 as Delhi’s predominant pollutant on November 8, with firecracker emissions adding to its levels.

Their size matters because fine particles can pass beyond the body’s larger-particle defenses and travel deep into the lungs. Established health science also links prolonged exposure to fine particulate matter with respiratory and cardiovascular risks, although the article itself reports only that residents experienced difficulty breathing. Smoke from crackers, vehicle emissions, and other combustion sources can add such particles.

Delhi’s readings showed why PM2.5 was a serious concern. The daily average AQI reached 376, and the overall AQI was 371 at 10 p.m. The haze reduced visibility across parts of the capital. With severe air forecast for several days, continued exposure remained a concern after the festival night.