While official forecasts have suggested potential weather shifts that could help disperse pollutants, scientists caution that air quality may remain poor in the coming days without sustained reductions in emissions.

Delhi and the wider National Capital Region (NCR) are grappling with an unprecedented air pollution crisis as dense smog blanketed the city over the weekend and into Monday, pushing the Air Quality Index (AQI) into “severe” and “severe-plus” hazard categories. With safety risks escalating across all age groups, authorities have activated Stage IV of the Graded Response Action Plan (GRAP-4) and rolled out emergency pollution control measures that are disrupting daily life, education, travel and work in the capital.

In a letter addressed to the chief secretaries of Delhi, Haryana, Rajasthan, and Uttar Pradesh on Saturday, the Commission for Air Quality Management (CAQM) expressed concern that “some schools and institutions in Delhi-NCR were still holding outdoor sports activities” despite prior directives aligned with a Supreme Court order from November 19.

The CAQM described this as “contrary to the spirit and intent of the apex court’s observations and the Commission’s instructions”.

In its earlier letter dated November 19, the Commission had urged the “postponement of physical sports competitions scheduled during November and December”.

Smog Shrouds the Capital; AQI Nears 500

Dense smog and stagnant winter weather conditions have driven Delhi’s AQI to some of the worst levels recorded this season – hovering perilously close to 500 in multiple monitoring stations and exceeding that figure at times. In some localities such as Jahangirpuri, the index reached as high as 498, while other parts of the NCR, including Bahadurgarh in Haryana, recorded levels above 460, illustrating the crisis’s regional scale.

The thick haze dramatically reduced visibility, hampering everyday activities and posing serious public health hazards. Hospitals and clinics across the city reported surges in patients with respiratory distress, eye discomfort and aggravated chronic conditions – especially among children, the elderly, and people with pre-existing health issues. Public health advisories strongly discouraged outdoor exposure without protective masks.

GRAP-4 Emergency Measures: What’s Changed

In response to the hazardous air quality, the Commission for Air Quality Management (CAQM) invoked Stage IV of the Graded Response Action Plan (GRAP) – the highest level of pollution control response. Under GRAP-4, emergency restrictions now implemented across Delhi-NCR include:

• Bans on most construction and demolition activities to reduce dust pollution.
• Severe limits on vehicle movement, particularly diesel and older vehicles, with exceptions only for essential or cleaner fuel-compliant transport.
• Restrictions on truck entry into the capital, with exceptions for essential goods and vehicles powered by cleaner fuels such as CNG, LNG or electric.
• Workplace and school adjustments, including directives for hybrid or online education and reduced in-office staffing where possible.
• Suspension of outdoor sports and public events to minimize vulnerable populations’ exposure to toxic air.

These measures aim to limit emissions and slow pollution accumulation at a time when weather conditions, including low wind speeds and cooler temperatures, are trapping pollutants close to the ground.

Disruptions and Public Response

The emergency restrictions have had immediate effects on everyday life in the region. Schools across parts of Delhi, Noida, Gurugram and other NCR districts shifted to hybrid or online learning models for younger students to reduce their health risks. Offices have been advised to adopt partial work-from-home arrangements, and residents are being urged to avoid non-essential travel.

Transportation has also felt the strain. Airlines such as IndiGo and Air India issued travel advisories as smog and low visibility disrupted operations at Delhi airports, potentially affecting hundreds of flights and causing delays and cancellations.

Public reaction to the pollution crisis has ranged from anger and frustration to anxiety over long-term health impacts. Many residents criticised authorities for ‘reactive’ rather than ‘preventive’ responses, arguing that temporary curbs fail to address structural causes such as vehicular emissions, industrial pollution, construction dust, and stubble burning in neighbouring regions.

“We are finding solutions to Delhi’s pollution problem while living and working in Delhi. We are not like those who leave Delhi to its fate and run away every six months to do vipassana,” Delhi chief minister Rekha Gupta said.

“My Delhi, my responsibility – we are working with this spirit. The problem is here, the solution will also be found here in Delhi…,” she said.

Health and Environment Risks Escalate

Medical experts warn that exposure to PM2.5 and other toxic airborne pollutants at these levels can have serious short- and long-term health consequences – even after air quality improves. There are heightened concerns about the cumulative impact on children’s developing lungs, cardiovascular health risks among adults, and increased vulnerability for individuals with asthma, bronchitis, heart disease, or compromised immune systems.

Environmentalists say that short-term curbs, even at GRAP-4 severity, are a partial fix for a crisis driven by deep-rooted systemic issues. Long-term strategies, including accelerating electric mobility, reducing industrial emissions, improving public transport, and coordinated regional action on agricultural burning, will be essential to meaningfully reduce the recurring winter pollution peaks.

Outlook: When Will Conditions Improve?

While official forecasts have suggested potential weather shifts that could help disperse pollutants, scientists caution that air quality may remain poor in the coming days without sustained reductions in emissions. The effectiveness of emergency GRAP-4 measures will depend on strict implementation and community cooperation, particularly in adopting cleaner transport choices and minimising activities that generate pollution.