Delhi’s air quality plunged into the ‘severe’ category on Saturday, with the Air Quality Index (AQI exceeding 400 across large parts of the city, prompting authorities to enforce Stage III of the Graded Response Action Plan (GRAP) in the national capital and the wider Delhi-NCR region.

Thick smog, low visibility and rising health concerns forced officials to ban many polluting activities, restrict workplace attendance and issue health advisories amid early winter conditions.

AQI Spikes, Smog Thickens and Authorities Act

Delhi’s toxic smog envelope worsened through the early hours of Saturday, with many monitoring stations recording AQI values in the severe bracket, well above the 400 threshold that signals a public health emergency.

The Central Pollution Control Board (CPCB) and other monitoring stations indicated readings upwards of 400 at multiple locations, deteriorating sharply from the ‘very poor’ category seen earlier in the week.

In response, the Commission for Air Quality Management (CAQM) re-imposed Stage III GRAP restrictions, which are activated when pollution crosses defined emergency levels. Under these measures:

• Non-essential construction and demolition work has been halted.
• Brick kilns, stone crushers and certain industrial operations are shut down temporarily.
• Older diesel vehicles and heavy polluters face restrictions on movement.
• Schools up to Class 5 have been directed to shift to hybrid learning modes for student safety.
• Offices across Delhi-NCR may operate with reduced staff to limit traffic.

CAQM officials emphasised that these curbs aim to tackle emission sources rapidly and prevent further deterioration, especially given weather conditions – low wind speeds, calm atmosphere and colder mornings.

The Indira Gandhi International (IGI) Airport also issued advisories to passengers as heavy smog lowered visibility, advising travellers to stay in contact with their airlines even though flight operations continued under low-visibility procedures.

Locals reported blurred skylines, gritty air and worsening respiratory discomfort. Commuters and residents had to wear masks outdoors as anxiety rose over the hazardous conditions that experts warn pose significant health risks for vulnerable populations, including children, the elderly and people with heart and lung conditions.

Why Pollution has Surged Again

Air quality in Delhi regularly deteriorates during late autumn and early winter. This year has been no different. A combination of factors has contributed to this recurring crisis:

Cold weather and stable winds: As temperatures fall, atmospheric conditions become more stable. Low winds mean pollutants do not disperse easily, instead accumulating near ground level where people breathe.

This phenomenon – common in northern India’s winter months – intensifies smog formation. Environmental analysts explain that calm atmospheric conditions trap emissions close to the city.

Persistent emission sources: Vehicular pollution, dust from roads and construction sites, as well as industrial emissions continue to contribute significantly. Despite ongoing curbs and regulations, these sources remain active and often difficult to control swiftly.

Regional pollution drivers: Seasonal agricultural burning in neighbouring states has also been identified as a contributing factor in past pollution spikes, adding to the city’s already stressed air quality during winter months. National health experts have emphasised that regional coordination is essential to tackle such cross-boundary pollution.

This winter’s spike marks one of the earliest and most abrupt deteriorations, with AQI climbing rapidly from ‘very poor’ to ‘severe’ within days. Officials are closely watching forecasts of continued still conditions and low temperatures, which could sustain or worsen the crisis.

Public Health Impact and Community Response

Public health experts have reiterated that prolonged exposure to severe air pollution can lead to acute and chronic health problems. Pollutants like PM2.5 – tiny particulate matter that penetrates deep into the lungs – are especially dangerous. Studies link high PM2.5 exposure with respiratory illnesses, heart disease, stroke, and other serious conditions.

Doctors and clinics across the city have noted an uptick in patients with breathing difficulties, coughing, eye irritation and throat infections over the past week. Many residents spoke of feeling trapped indoors or struggling to carry out routine tasks in the hazardous air.

Civil society groups and environmental activists have urged citizens to reduce reliance on private vehicles, use public transport where possible, and avoid outdoor exercise during peak smog periods. They also called on authorities to adopt long-term, sustainable solutions beyond reactive emergency measures.

The Logical Indian’s Perspective

The recurring air quality crisis in Delhi isn’t merely a seasonal inconvenience – it is a public health emergency that demands deep structural change.

Short-term curbs like GRAP Stage III are necessary to mitigate acute spikes, but they do not address the underlying causes: unchecked emissions, inadequate regional coordination, lax enforcement and insufficient green infrastructure.

We must remember that clean air is a fundamental right, not a privilege reserved for a few weeks in a year. Emergency responses, though vital during severe episodes, should not be the default strategy.

Policymakers, city planners, industry leaders and citizens must collaborate on sustained action – investing in cleaner public transport, electrification of vehicles, industrial emissions control, and cooperative policies with neighbouring states to reduce agricultural burning.

Empathy for those most affected – children, outdoor workers, elderly people and those with respiratory conditions – should guide these long-term frameworks. Lasting solutions will come through patience, shared responsibility and unwavering commitment to environmental justice.