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Air pollution: NCAP and standards
The National Clean Air Programme has run since 2019, and its scoreboard is ambiguous: most of its 130 cities have cleaner air than in 2017–18, but only fourteen of them meet the national standard. The ranking that goes with the programme rewards effort rather than measured results, and the country is still arguing about how to count a stubble fire.
UPSC has asked
- Prelims 2022: the WHO Air Quality Guidelines
- Prelims 2016: the gases used to calculate the Air Quality Index
The programme
- The National Clean Air Programme (NCAP) was launched in 2019 and covers 130 cities, most of them non-attainment cities.
- It aims to cut PM10 by up to 40 per cent by 2025–26, measured against 2017–18.
- Cities are paid through performance linked grants, tracked on the Portal for Regulation of Air Pollution in Non-Attainment cities (PRANA).
The ranking
- Swachh Vayu Survekshan, begun in 2022–23, ranks NCAP cities in three population groups on what they do about dust, waste burning, vehicles and industry.
- It rewards effort over results: measured PM10 improvement carries only 2.5 per cent of the weightage.
How the air is measured
- The National Ambient Air Quality Standards cover twelve pollutants, and the Air Quality Index combines eight of them, particulate matter (PM10 and PM2.5), NO₂, SO₂, CO, O₃, NH₃ and lead, taking whichever is worst.
- Carbon dioxide and methane are not among them, so the index says nothing about the greenhouse gases.
- It runs in six bands, from Good, 0 to 50, to Severe, 401 to 500.
- Ambient air is sampled manually over 24 hours and read continuously at Continuous Ambient Air Quality Monitoring Stations (CAAQMS).
- The annual PM10 standard is 60 micrograms per cubic metre, four times the World Health Organization (WHO) guideline of 15.
- The Central Pollution Control Board (CPCB) is statutory under the Water Act, 1974, and the Commission for Air Quality Management (CAQM) under its own Act of 2021.
Two ways to count a stubble fire
Fire counts
- Active fires seen during daytime satellite passes
- Miss fires lit after the satellites have gone
Burnt area
- Scorched fields mapped from Sentinel-2 images
- Says nothing about how much smoke a fire released
- Farm fires add no more than 15 per cent of winter particulate pollution, but more than a third on some October and November days.
What has happened
7 Sep 2026
The Centre released NCAP's results and the Swachh Vayu Survekshan 2026 rankings on Swachh Vayu Diwas, the International Day of Clean Air for Blue Skies.
- Against 2017–18, 108 of the 130 cities had lower annual PM10, 26 cut it by more than 40 per cent, and 14 met the standards.
- Of ₹16,423.55 crore in grants since 2019–20, 70.5 per cent has been used.
- Lucknow topped the largest cities although its PM10 is more than twice the national standard.
PIB, 7 Sep 2026: India's Path to Blue Skies: From Awareness to Action for Cleaner Air (opens in a new tab) · The Indian Express, 7 Sep 2026: Lucknow's air cleanest, Indore among top 3 in Centre's annual survey (opens in a new tab)
4 Sep 2026
CAQM opened talks with Punjab and the Indian Space Research Organisation (ISRO) on how stubble burning is counted, doubting that fire counts capture it.
- Peak burning moved from about 1.30 pm in 2020 to about 5 pm in 2024, after the satellites have passed.
- Fire counts in Punjab and Haryana fell 93 and 91 per cent from 2021 to 2025, but burnt area fell far more slowly.
- The burnt area protocol is being re-tested as satellite and ground data diverge.
The Hindu, 4 Sep 2026: Air quality panel holding talks with Punjab govt. and ISRO over tracking of stubble fires (opens in a new tab) · The Indian Express, 7 Sep 2026: Air quality management body to re-test burnt area protocol as satellite, ground data diverge (opens in a new tab)
25 Aug 2026
The National Green Tribunal gave the CPCB ten weeks to standardise testing for three further ambient air pollutants.
- They are aluminium, iron and silica.
The Hindu, 25 Aug 2026