The Delhi-NCR air quality monitoring framework is being strengthened by augmenting the Continuous Ambient Air Quality Monitoring Stations (CAAQMS) network to improve spatial coverage and data reliability. The initiative will enhance real-time surveillance and support policy for pollution abatement. The Commission for Air Quality Management in NCR and Adjoining Areas has reviewed the planned addition of 27 new CAAQMS above the existing 84 stations.

Six of the new stations have been installed in Delhi, while seven in Haryana, four in Rajasthan and 10 in Uttar Pradesh are being installed. The existing network includes 40 stations in Delhi, 22 in Haryana-NCR, four in Rajasthan-NCR and 18 in Uttar Pradesh-NCR. Staged installation will maintain continuity and allow validation of data streams.

Deliberations set scientific criteria to ensure monitoring density reflects population distribution and land use, including residential, traffic, industrial and background areas. Urban contiguity and rapid peri-urban expansion were considered, with a shift towards grid-based spatial coverage to provide even representation. Background and border stations were identified as necessary to understand pollutant transport and baseline conditions affecting Delhi-NCR.

Norms have been framed for Delhi and contiguous cities such as Ghaziabad, Noida, Greater Noida, Faridabad and Sonepat, targeting approximately one station per 25 sq. km grid, defined as a five km by five km area, while other district headquarters will have one station per 50 sq. km. Coverage in peri-urban and suburban areas is critical for assessing inflow and outflow of pollution and the impact of urban sprawl on regional air quality. The grid approach is intended to balance population based needs with land use and deployment considerations.

On this basis, 46 additional stations, including 14 in Delhi, 16 in Haryana, one in Rajasthan and 15 in Uttar Pradesh, shall be installed to strengthen the monitoring infrastructure and ensure uniform coverage across Delhi-NCR. The total number of CAAQMS would rise to 157, comprising 60 in Delhi, 45 in Haryana, nine in Rajasthan and 43 in Uttar Pradesh. The Commission concluded that a dense and robust monitoring network is vital for identifying pollution sources, tracking trends and enabling timely policy action to mitigate air pollution in the region.