Bengaluru, Kalaburagi, Davangere, and Hubballi-Dharwad are cities and towns in the State that have been deemed as “non-attainment cities” by the National Green Tribunal (NGT). Such cities are defined as ones where the air quality, as per the records maintained by the Central Pollution Control Board (CPCB), is polluted beyond the prescribed National Ambient Air Quality Standards.
The NGT, which put out an order on Monday directing cities and towns where the average ambient air quality in November fell under ‘moderate’ or below category to allow only green firecrackers, has also said that the tribunal might have to consider issuing directions to prohibit the use of firecrackers during the period if the air quality is beyond the threshold.
The order mentions that bursting green crackers may be allowed for two hours during Deepavali. The NGT has specified that data from November 2019 should be considered to ascertain the average ambient air quality. The order also states that if the States do not specify the timings for use of green crackers, the timings would be from 8 p.m. to 10 p.m. on Deepavali.
The Karnataka government, in an order dated November 6, had issued guidelines for the sale and bursting of only green crackers during Deepavali. However, the government had not specified any timings.
Though the Chief Secretary and the Forest and Environment Minister were unavailable for comment, officials in Karnataka State Pollution Control Board (KSPCB) said that various parts of the city generally record ‘moderate’ air quality and ascertaining the average for the whole city would be difficult as monitoring stations were set up across Bengaluru. Areas in the city, including City Railway Station, Silk Board, and Hebbal, generally record “moderate ambient air quality”, an official said.
“However, generally we can say that the city is between satisfactory and moderate and has probably never gone beyond the moderate category,” the official said, adding that as the State government had already allowed only green crackers, only the direction on timings needed to be clarified. The Air Quality Index (AQI) is identified through graded measures in six ranges and categories: 0-50 is good; 51-100 is satisfactory; 101-200 is moderate; 201-300 is poor; 301-400 is very poor; and above 401 is severe.
According to data from Manual Ambient Air Quality Monitoring Stations in Bengaluru for November 2019, obtained from 13 stations, five reported ‘moderate’ ambient air quality (AMCO Batteries, Mysuru Road; Arvind Motors Pvt. Ltd., Peenya Industrial Area; TERI premise, Domlur; Banaswadi police station, Banaswadi; and SKR Building, K.R. Circle). However, though Central Silk Board and ITPL fell under ‘satisfactory’, their index values were 100 and 99, respectively.
An expert working in the field of air quality said there were two methods of measuring AQI. “One is through the Manual Ambient Air Quality Monitoring Stations, where data is obtained frequently, and the other is through the Continuous Ambient Air Quality Monitoring Stations, where data is obtained on real-time basis. Hence, the measures might not be the same in both.”