GUWAHATI, Nov 7 - The verdict is out. The air and noise pollution in the city during Diwali was relatively less this year, according to analysis of tests conducted by the Pollution Control Board, Assam (PCBA).
The PCBA had monitored the noise level at two locations – Harisabha (Panbazar) and Nayanpur (Ganeshguri) – during Diwali.
The noise level in both the locations on the day was much below the permissible limit.
At Panbazar, the average noise level, measured on hourly basis from 6 pm to 12 pm, was in the range of 89.3 dB (decibel) and 94.1 dB. The noise level had reached 105 dB between 9 pm and 10 pm.
Permissible noise limit for firecrackers is 125 dB.
Ganeshguri was quieter compared to last year. The average noise level was in the range 65.1 dB and 74.2 dB, the highest (94.9 dB) noted between 8 pm and 9 pm.
Last year, the average noise level on the Diwali day at Ganeshguri was 74.2 dB, the highest level noted this year. At Panbazar, the average noise level during last year’s Diwali was 82.3 dB.
Ambient air quality during Diwali in the city was also little better than last year.
The air quality was measured at six locations – Bamunimaidam, Bharalumukh, Rehabari, Khanapara, Gauhati University and Boragaon.
The sulphur dioxide (SO2) level was in the range of 6-10 mg/m3 while the nitrogen dioxide level was 16 to 20 mg/m3 . The National Ambient Air Quality standards for both the gases is 80 mg/m3 . Last year, the parameters of the two gases in four city locations during Diwali was in the range of 12.20-14.90 mg/m3 and 18.10-21.20 mg/m3 respectively.
However, presence of particulate matter (PM10) in the six locations this Diwali was in the range 79 mg/m3 (Boragaon) and 235 mg/m3 (Rehabari). The prescribed national standard for PM10 is 100 mg/m3 .
Last year, the presence of particulate matter during Diwali in four locations was in the range of 148.90 to 169.30 mg/m3 .
Officials at the PCBA said that joint teams had conducted checks at the stockists. “We had tested the firecrackers being sold at various places. All the firecrackers tested had a noise level of below 125 dB, the maximum permissible limit,” they said.