Delhi AQI hits 331 as pollution spikes ahead of Diwali, many areas in severe zone

An AQI of 331 places Delhi in the ‘very poor’ category. The article reports that the city’s average AQI reached 331 at 7 am, showing a major deterioration just before Diwali. AQI is a scale used to communicate how polluted the air is and how concerning conditions may be.

The ‘very poor’ range runs from 301 to 400. The ‘severe’ range runs from 401 to 500. Delhi’s average remained below 401, but eight individual stations crossed that threshold. Bawana, Punjabi Bagh, Rohini, Vivek Vihar, Narela, Jahangirpuri, Alipur and DTU recorded severe readings.

This difference matters because pollution is not uniform across a city. One area may record 331, while another records above 400. The rising AQI triggered GRAP-2 measures, including stronger dust controls and efforts to encourage public transport. If readings rise further, more restrictive GRAP stages can apply.

Pollution was widespread rather than limited to a few Delhi neighbourhoods. Of Delhi’s 58 monitoring stations, 33 recorded ‘very poor’ air and eight recorded ‘severe’ air. Together, 41 stations showed one of these two highest reported categories in the article.

The most affected stations included Bawana, Punjabi Bagh, Rohini, Vivek Vihar, Narela, Jahangirpuri, Alipur and DTU. Other readings were close to severe: Sonia Vihar recorded 393, Pusa 390, Burari Crossing 382 and DU’s North Campus 386. These figures show how uneven but broadly intense the pollution was.

The haze also covered the wider NCR. Noida’s average AQI was 307, placing it in the ‘very poor’ category. Gurugram recorded 284 and Ghaziabad 259, both ‘poor’. High-rise buildings in Noida and Gurugram disappeared behind smog, showing the regional scale of the episode.

The article focuses on AQI readings and government measures, not medical symptoms. Established health guidance links prolonged exposure to heavily polluted air with eye and throat irritation, coughing, breathing difficulty and reduced lung function. The risk generally increases as pollution becomes more intense and lasts longer.

Very poor or severe air can also worsen asthma, chronic lung disease and some heart conditions. Tiny particles can enter deep into the lungs, and the smallest particles may pass into the bloodstream. Short-term exposure may aggravate symptoms, while repeated or prolonged exposure is associated with more serious health risks.

Delhi’s readings make this important. The city’s average AQI was 331, while eight stations exceeded 400. People who are sensitive to pollution may need to reduce outdoor exposure and follow official health advice. The article itself does not provide medical recommendations or report specific health outcomes from this episode.

The article connects the deterioration with Diwali’s approach and the onset of Delhi’s winter pollution season. It reports a thick smog blanket, an AQI of 331 and several stations above 400 just days before Diwali. The Supreme Court therefore allowed only limited green-cracker use on November 7 and 8.

The article does not fully explain why winter traps pollution. Established atmospheric science shows that weak winds, limited vertical mixing and temperature inversions can prevent pollutants from dispersing. Emissions from vehicles, dust, industry and fires can then accumulate near the ground. Fireworks can add a short, sharp pollution increase around celebration periods.

Delhi’s winter anti-pollution drive began on November 1 and will continue until February 28. GRAP-2 was also invoked because forecasts suggested very poor air would continue. The article indicates that pollution may remain a problem over the coming days, especially as Diwali approaches.

GRAP, or the Graded Response Action Plan, is a phased emergency response mechanism for preventing further deterioration in air quality. It links increasingly strong government measures to AQI bands. This allows authorities to respond progressively instead of using the same restrictions at every pollution level.

Stage 1 applies at AQI 201-300, Stage 2 at 301-400, Stage 3 at 401-450 and Stage 4 when AQI crosses 450. Stage 2 measures include mechanical road sweeping, water sprinkling, anti-smog guns and higher parking fees to discourage private vehicle use. The article says Stage 3 restrictions also cover certain older vehicles in parts of the NCR.

Delhi entered Stage 2 after its average AQI moved into the very poor category. The CAQM had introduced Stage 1 on October 21, when air quality became poor. The framework is designed to intensify controls if pollution continues rising, while easing them when conditions improve.

Authorities can use targeted controls instead of imposing a blanket ban on all activity. Under GRAP-2, the article lists regular mechanical road sweeping, water sprinkling, anti-smog guns and increased parking fees. These measures focus on dust, traffic and vehicle use while allowing essential movement and services to continue.

Mechanical sweepers collect dust from roads, while water sprinkling helps prevent loose particles from becoming airborne. Anti-smog guns spray fine water droplets that can help settle dust near pollution hotspots. Better public transport, supported by higher parking fees, can reduce the number of private vehicles and therefore traffic-related emissions. The article describes public transport as something authorities should encourage.

These actions work best when applied consistently and monitored. Delhi also introduced round-the-clock enforcement checks and automatic number-plate recognition cameras. The measures matter because pollution was widespread: 33 stations were very poor and eight were severe, while forecasts expected very poor air to continue.

Particulate matter, or PM, is a mixture of extremely small solid particles and liquid droplets suspended in air. Some particles come from dust, vehicles, industry and burning. Their small size allows them to remain airborne and travel across areas. Smaller particles can penetrate deeper into the respiratory system than larger dust particles.

Atmospheric dispersion is the spreading and dilution of pollutants by wind, turbulence and vertical air movement. When these processes are weak, emissions stay concentrated near the ground. A temperature inversion, for example, can place warmer air above cooler surface air and act like a lid. Calm conditions can produce a similar buildup.

The article describes Delhi as covered by a thick smog blanket, with haze extending to Noida and Gurugram. It does not identify the exact weather conditions during this episode. However, the reported spread and the forecasts of continued very poor air show why pollution can persist across the region.