Air Quality in the NCR and the CAQM: The Commission for Air Quality Management in National Capital Region and Adjoining Areas Act, 2021, GRAP and the Sources of Delhi's Smog

Every winter the National Capital Region is covered by a grey haze, and the Air Quality Index climbs into the 'severe' range. The causes are many: vehicle exhaust, road and construction dust, industries and power plants, household fuels, waste burning, firecrackers, and the burning of paddy stubble in Punjab and Haryana, all trapped by cold, still air. Because the airshed crosses State boundaries, no single State can solve the problem, and for decades the Supreme Court filled the gap through the M.C. Mehta litigation and its Environment Pollution (Prevention and Control) Authority (EPCA). In 2021, Parliament created a statutory body with overriding powers over the whole airshed: the Commission for Air Quality Management in National Capital Region and Adjoining Areas (CAQM).

1. Background: From EPCA to CAQM

In 1998, on the Supreme Court's direction in M.C. Mehta v. Union of India (the Delhi vehicular pollution case), the Central Government constituted the EPCA under Section 3(3) of the Environment (Protection) Act, chaired by Bhure Lal. EPCA oversaw the conversion of Delhi's buses, taxis and autos to CNG (mandated by the Supreme Court in 1998 and enforced by 2002), the introduction of the Graded Response Action Plan in 2017, and many other measures. But it had no statutory powers of its own, depended on the Court for enforcement, and covered only the NCR, not the stubble-burning areas beyond it.

In October 2020, while the Supreme Court was considering appointing a one-member committee on stubble burning (in Aditya Dubey v. Union of India), the Centre promulgated the Commission for Air Quality Management in National Capital Region and Adjoining Areas Ordinance, 2020, dissolving EPCA. After a re-promulgation in April 2021, Parliament enacted the Commission for Air Quality Management in National Capital Region and Adjoining Areas Act, 2021 (Act No. 29 of 2021) in August 2021.

2. Constitution of CAQM

Under Section 3, the Central Government constitutes the Commission, a body corporate, consisting of:

• a full-time Chairperson who has been a Secretary to the Government of India or a Chief Secretary of a State, or has at least fifteen years' experience in environmental protection and pollution control, or twenty-five years' administrative experience;
• an officer of the rank of Joint Secretary as an ex officio member (full-time) and an officer of that rank as Member-Secretary and chief coordinating officer;
• five ex officio members, being the Chief Secretaries or Secretaries in charge of environment of Delhi, Punjab, Haryana, Rajasthan and Uttar Pradesh;
• three full-time independent technical members with expertise in air pollution;
• one technical member from the CPCB and one technical member nominated by ISRO;
• three members from non-governmental organisations with experience in combating air pollution; and
• associate members representing Central ministries such as Road Transport, Power, Housing and Urban Affairs, Petroleum and Natural Gas, Agriculture, and Commerce and Industry.

The Chairperson and members are appointed on the recommendation of a selection committee chaired by the Union Minister of Environment, with other Union Ministers and the Cabinet Secretary. The Commission works through sub-committees for monitoring and identification, safeguarding and enforcement, and research and development. It reports annually to Parliament.

3. Jurisdiction of CAQM

The Commission's jurisdiction extends to the National Capital Region (as defined in the National Capital Region Planning Board Act, 1985, covering Delhi and specified districts of Haryana, Uttar Pradesh and Rajasthan) and to adjoining areas, meaning areas in the States of Haryana, Punjab, Rajasthan and Uttar Pradesh adjoining the NCR where any source of pollution may cause an adverse impact on air quality in the NCR. The inclusion of 'adjoining areas' is what enables the Commission to regulate stubble burning in Punjab and thermal power plants beyond the NCR. Under the Act, the Commission's jurisdiction on matters of air quality management in this region is overriding, and civil courts are barred from entertaining suits on matters within its purview. Appeals against its orders lie to the National Green Tribunal.

4. Powers and Functions of CAQM

Under Section 12, the Commission has the power to take all such measures, issue directions and entertain complaints as it deems necessary for protecting and improving air quality in the NCR and adjoining areas. In particular it may:

1. coordinate actions by the States and agencies, and plan and execute a plan for prevention, control and abatement of air pollution;
2. provide a framework for identifying air pollutants and conduct research on the sources;
3. lay down parameters for air quality and standards for emissions or discharge of air pollutants from various sources, including more stringent standards than national norms where needed;
4. restrict the setting up of industries in any area, and regulate or prohibit any activity that may cause pollution;
5. inspect premises, plants and equipment, and investigate violations;
6. issue directions to any person, officer or authority, including for closure, prohibition or regulation of any industry or process, and stoppage or regulation of electricity, water or other services; and
7. prepare manuals and codes, promote awareness, and train personnel.

4.1 Directions of CAQM

Directions under Section 12 are binding on the person or authority to whom they are issued. In case of any conflict between the directions of the Commission and those of a State Government, the CPCB, a State Pollution Control Board or any other authority, the Commission's directions prevail. Its directions have included: switching industries in the NCR to PNG or approved fuels and banning coal in industrial and domestic use (from 1 January 2023, except thermal power plants); mandatory biomass co-firing in thermal power plants within 300 kilometres of Delhi (with show-cause notices and penalties for non-compliance in 2025); dust-control registration and self-audit for construction sites above a threshold area; restrictions on diesel generator sets; and the Graded Response Action Plan.

4.2 Offences, penalties and environmental compensation

Section 14 makes non-compliance with the Act or the Commission's directions punishable with imprisonment up to five years, or fine up to Rs 1 crore, or both. By a proviso inserted when the Ordinance became an Act, these penal provisions do not apply to farmers for stubble burning. Instead, Section 15 empowers the Commission to impose and collect environmental compensation from farmers causing air pollution by stubble burning, at prescribed rates. After the Supreme Court criticised the nominal fines and weak enforcement in October 2024, the Centre doubled the rates on 6 November 2024: Rs 5,000 per incident for holdings under two acres, Rs 10,000 for two to five acres, and Rs 30,000 for more than five acres.

5. CAQM, CPCB and State Pollution Control Boards

5.1 CAQM versus CPCB

The CPCB is a national body under the Water and Air Acts, setting National Ambient Air Quality Standards, coordinating State Boards, advising the Centre and running the national monitoring network. The CAQM is a regional body for one airshed, with power to set stricter NCR-specific standards and to issue binding directions that override the CPCB's in case of conflict. The CPCB is represented on the Commission through a technical member, and its data and technical support are used by the Commission. In effect, the CPCB remains the national standard-setter and technical arm, while the CAQM is the regional command centre for the NCR.

5.2 CAQM versus State Pollution Control Boards

The State Pollution Control Boards of Haryana, Uttar Pradesh, Rajasthan and Punjab, and the Delhi Pollution Control Committee, continue to grant consents, inspect units and prosecute under the Air Act. But in the Commission's region they act under its directions, which prevail over their own. The Commission's flying squads inspect sites and recommend closure, and the Boards implement the closures. The relationship is one of direction and execution: the Commission sets the plan, and the Boards and district administrations carry it out.

6. Air Quality Index and the Graded Response Action Plan

6.1 Air Quality Index

The National Air Quality Index (AQI), launched in October 2014, converts concentrations of up to eight pollutants (PM10, PM2.5, nitrogen dioxide, sulphur dioxide, carbon monoxide, ozone, ammonia and lead) into a single number with a colour code. The overall AQI is the sub-index of the worst pollutant. It has six categories: Good (0 to 50), Satisfactory (51 to 100), Moderately polluted (101 to 200), Poor (201 to 300), Very poor (301 to 400) and Severe (401 to 500). The AQI is a communication tool; the legal standards remain the National Ambient Air Quality Standards of 2009.

6.2 Graded Response Action Plan

The Graded Response Action Plan (GRAP) is a set of emergency measures triggered as air quality worsens. It was first notified in January 2017 on the Supreme Court's direction, implemented by EPCA, and taken over by the CAQM, which revised it in 2022 to operate proactively on the basis of forecasts, not only after the AQI has crossed a threshold. It has four stages:

The CAQM has revised GRAP more than once to move measures to earlier stages, including in December 2024 and November 2025, when, following a Supreme Court order permitting stricter action, several Stage IV measures were applied at Stage III. Studies have found that GRAP is often invoked reactively after the AQI has already crossed thresholds, and that short-term measures cannot substitute for year-round control of sources.

7. NCR Air Pollution and Its Sources

NCR air pollution is the result of year-round local sources combined with seasonal episodes and meteorology. In winter, low wind speeds, falling temperatures and temperature inversion trap pollutants close to the ground, while north-westerly winds carry smoke from stubble fires. Source apportionment studies (including IIT Kanpur's 2016 study and later ones) identify vehicles, road and construction dust, industries and power plants, biomass and waste burning, and secondary particles formed from gases as the main contributors, with stubble smoke adding a large share on peak days in October and November. The National Clean Air Programme (2019) sets city-level targets for reduction of particulate matter, and Delhi and other NCR cities are 'non-attainment cities' under it.

7.1 Stubble burning

In Punjab and Haryana, farmers harvest paddy in October and must sow wheat within a few weeks. Laws such as the Punjab Preservation of Subsoil Water Act, 2009, which delayed paddy transplanting to conserve groundwater, compressed this window; combine harvesters leave tall stubble; and burning is the cheapest way to clear fields. The legal and policy response includes: the NGT's 2015 order in Vikrant Kumar Tongad v. EPCA prohibiting crop residue burning in Punjab, Haryana, Rajasthan and Uttar Pradesh; the Crop Residue Management scheme subsidising machines such as the Happy Seeder and super straw management systems; the bio-decomposer spray; ex-situ use of straw in biomass power, bio-CNG and co-firing in thermal plants; satellite monitoring of fire counts; the CAQM's framework and State action plans; and environmental compensation under Section 15 of the Act. The Supreme Court has repeatedly directed Punjab and Haryana to enforce the ban while also providing incentives, recognising that farmers need viable alternatives.

7.2 Vehicular pollution in the NCR

Vehicles are the largest year-round local source of PM2.5 and nitrogen oxides. Key measures have been: the conversion of public transport to CNG (1998 to 2002); leapfrogging from BS-IV to BS-VI fuel and vehicles nationally from 1 April 2020, on the Supreme Court's direction; the ban on diesel vehicles older than ten years and petrol vehicles older than fifteen years in Delhi NCR (NGT 2015, upheld by the Supreme Court in 2018); PUC certification and RFID tolling to cut congestion; the entry of trucks into Delhi restricted and an environment compensation charge on commercial vehicles; the Eastern and Western Peripheral Expressways to divert through-traffic; and promotion of electric vehicles and the metro. In 2025, a CAQM direction to deny fuel to end-of-life vehicles in Delhi from 1 July 2025 was put on hold after public resistance, and the age-based ban came up for re-examination before the Supreme Court.

7.3 Construction and demolition dust

Road dust and construction and demolition dust are major sources of PM10. The CAQM requires projects above a threshold plot area to register on a dust control portal and self-audit compliance with dust mitigation measures: covering of materials, wind-breaking screens, water sprinkling, anti-smog guns on large sites, covered transport of debris, and on-site C&D waste management. Construction is progressively restricted under GRAP Stages III and IV. The Environment (Construction and Demolition) Waste Management Rules, 2025 add recycling obligations for large projects.

7.4 Industrial air pollution in the NCR

Industrial measures include: the Supreme Court's 2017 ban on pet coke and furnace oil in the NCR; the CAQM's shift of industries to PNG and approved fuels and the ban on coal from January 2023; conversion of brick kilns to zig-zag technology; online continuous emission monitoring in red category industries; closure of Delhi's coal power plants (Badarpur and Rajghat); emission norms and flue gas desulphurisation for thermal plants within 300 kilometres, though the Centre relaxed the FGD requirement for many plants in 2025; and biomass co-firing directions. Diesel generator sets must use dual-fuel kits or retrofitted emission control devices, and are restricted under GRAP.

8. Coordination between NCR States

The NCR spans Delhi and districts of Haryana, Uttar Pradesh and Rajasthan, and the airshed is also affected by Punjab. Each State has its own government, pollution control board, transport department and political priorities. Coordination failures have been common: disputes over who is responsible for stubble burning, inconsistent enforcement of vehicle and fuel bans, and delays in public transport links. The CAQM was designed to solve this problem by giving a single statutory body representation from all five States and power to issue binding directions across the airshed. In practice, the Supreme Court continues to supervise the Commission and the States in the M.C. Mehta case, calling Chief Secretaries to account, and the effectiveness of coordination depends on the Commission's willingness to use its powers and the States' cooperation.

9. Critical Appraisal

The CAQM Act is a significant institutional innovation: it recognises that air pollution must be managed at the level of the airshed, not the State, and gives one body overriding powers across five States. It has achieved results in industrial fuel switching and dust control. But air quality in the NCR remains among the worst in the world. Criticisms include: the Commission's slow use of its penal powers, which drew Supreme Court censure in 2024; the exemption of farmers from penalties, leaving only modest compensation; reliance on emergency GRAP measures instead of structural reform; weak coordination with Punjab; limited public participation; and the absence of a comparable body for other polluted airsheds such as the Indo-Gangetic plain. A long-term solution requires cleaner transport, crop diversification and residue markets, regional industrial and energy transition, and consistent enforcement.

10. Related Topics and Provisions