Many towns in Haryana, including Gurugram and Faridabad, which lie next to the national capital Delhi, reported an Air Quality Index (AQI) of over 400.

Faridabad recorded an AQI of 414, Gurugram 425, Hisar 441, Jind 457 and Fatehabad 446. A day earlier, these towns had AQIs of 378, 358, 468, 459 and 471, respectively, according to the Central Pollution Control Board’s data.

Haryana’s Rohtak with an AQI of 397, Sirsa 360, Ballabgarh 378, Kaithal 367 and Kurukshetra 372 experienced ‘very poor’ air quality. A day earlier, the AQIs in these towns were 422, 418, 330, 377 and 357, respectively.

Among the Punjab towns with “very poor” air quality included Amritsar (374), Bathinda (354), Jalandhar (314) and Ludhiana (345). On Saturday the AQI in these towns was 313, 332, 294 and 300, respectively.

Chandigarh’s AQI fell in the moderate category both on Saturday and Sunday at 131 and 145, respectively.

About Air Quality Index

The National Air Quality Index (AQI) was launched in New Delhi on September 17, 2014, under the Swachh Bharat Abhiyan.

• The Central Pollution Control Board along with State Pollution Control Boards has been operating National Air Monitoring Program (NAMP) covering 240 cities of the country having more than 342 monitoring stations.
• An Expert Group comprising medical professionals, air quality experts, academia, advocacy groups, and SPCBs was constituted and a technical study was awarded to IIT Kanpur.
• IIT Kanpur and the Expert Group recommended an AQI scheme in 2014.
• While the earlier measuring index was limited to three indicators, the new index measures eight parameters.
• The continuous monitoring systems that provide data on near real-time basis are installed in New Delhi, Mumbai, Pune and Ahmedabad.
• There are six AQI categories, namely Good, Satisfactory, Moderately polluted, Poor, Very Poor, and Severe.
• The AQI considers eight pollutants (PM10, PM2.5, NO2, SO2, CO, O3, NH3, and Pb) for which short-term (up to 24-hourly averaging period) National Ambient Air Quality Standards are prescribed.

Based on the measured ambient concentrations, corresponding standards and likely health impact, a sub-index is calculated for each of these pollutants. The worst sub-index reflects overall AQI. Likely health impacts for different AQI categories and pollutants have also been suggested, with primary inputs from the medical experts in the group.