The Air quality Index (AQI) was found to be very poor in all monitoring stations in Chennai on Deepavali. Ambient noise level ranged from 55 to 66 decibel - dB(A) on Wednesday pre-Deepavali and 69 to 79 dB(A) on Thursday.
It was observed that the values were little higher for the Deepavali-2021 than 2020, according to a report by Tamil Nadu Pollution Control Board (TNPCB).
High relative humidity
The increase in air pollution level and AQI values are mainly due to high relative humidity (90 per cent and above) and low wind speed and heavy bursting of crackers during the permitted time, the report said.
The report of the Ambient Air Quality (AAQ) survey revealed that there was substantial increase in the values of PM10 (particulate matter below 10 microns) and PM2.5 (less than 2.5 microns) parameters in the five monitoring stations in the city compared to 2020.
The PM10 values ranged from 187 to 283 ug/m3 on Deepavali against the prescribed standard of 100 ug/m PM2.5. The PM10 and PM2.5 values are above National Ambient Air standards prescribed in all the stations on Deepavali.
The gaseous pollutant namely SO2 (sulphur dioxide) and NO2 (nitrogen oxide) were found to be well within the prescribed standard (80 ug/mo), the report said.
Manual monitoring
Based on the Supreme Court’s direction and the Central Pollution Control Board, the TNPCB conducted manual monitoring in five different locations in Chennai - Besant Nagar, T’ Nagar, Nungambakkam, Triplicane and Sowcarpet - to monitor the impact of Deepavali celebrations on Ambient Air Quality and also Noise pollution levels in Chennai, the report said.
Source: TNPCB
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C - Commercial