Mumbai: Air quality ‘poor’ but it was a ‘quieter’ Diwali

INDIAN EXPRESS

​Mumbai: Air quality ‘poor’ but it was a ‘quieter’ DiwaliThe data further shows that the air quality on October 30 night in Mumbai was better than that of Navi Mumbai and Delhi that registered air quality indices as worse as 309 and 452, respectively.
Written by Rohit Alok | Mumbai | Published:November 2, 2016 1:53 am 
Mumbai witnessed a spike in pollution levels a day after Diwali. AP
The air quality recorded on the night Mumbai celebrated Diwali was “poor” but, for the first time in a decade, the city experienced one of its most “quiet” Diwalis. According to System of Air Quality and Weather Forecasting and Research (SAFAR), on October 30 night, the air quality index (AQI) in Mumbai was 278, almost the same as last year’s Diwali at 279.
 The data gathered by SAFAR shows Andheri, Mazgaon and Malad were the worst-affected areas in the city. Malad reported the highest air pollution with an AQI of 311 on Sunday night. While Andheri and Mazgaon recorded 306 and 295, respectively, Borivali recorded the lowest air quality levels in the city.The data further shows that the air quality on October 30 night in Mumbai was better than that of Navi Mumbai and Delhi that registered air quality indices as worse as 309 and 452, respectively.
But Mumbai witnessed a spike in pollution levels a day after Diwali as the AQI went up to 318, falling under ‘very poor’ AQI category. AQI levels between 201 and 300 fall under ‘poor’ category and 301-400 is ‘very poor’, indicating a health risk for people sensitive to air pollution.
According to Neha Parkhi, a senior programmer with SAFAR, though air quality deteriorated in Mumbai post Diwali, it will improve in the coming days. “The air pollution was poor because of the low temperature and low wind speed that accumulated the emissions released on Sunday night. The humidity as well played a big role in trapping the particles during the peak pollution hours between 11 pm and 5 am on the intervening night of Sunday,” said Parkhi.
Mumbai’s temperatures recorded by the India Meteorological Department on Tuesday show a minimum of 22.2 degrees Celsius and a maximum of 36.1 degrees Celsius with a varying humidity of 50 per cent to 79 per cent.
Parkhi said on Monday morning, the lead pollutant was particulate matter (PM) 2.5 (small pollutant particles that can enter the lungs) and PM 10 (slightly larger, coarser particles). Both were expected twice more than their safe limits. As against the permissible limit of 60 microgrammes per cubic metre (µg/m3) for PM 2.5, levels were as high as 145.9µg/m3 in Mumbai. Similarly, PM 10 levels were 228.9µg/m3 against a safe limit of 100µg/m3.
Mumbai experienced one of its most quiet Diwalis this year with noise levels across the city well below violation levels. Activists said while the noise from most crackers was under the permissible limit, many violated the 10 pm deadline set by the Mumbai Police citing Bombay High Court orders and tenets of the Noise Pollution (Regulation and Control) Rules, 2000.
“Although Mumbaikars used fewer firecrackers, enforcement of time limits was inadequate as even at very prominent locations such as Marine Drive, the noisiest firecrackers were used after 10 pm, in spite of police presence. The highest reading of 113.5 dB was recorded at around 11.15 pm at Marine Drive,” said Sumaira Abdulali, convener, Awaaz Foundation.
On the night of October 30, activists spanned across the city noting the noise levels through meters. In comparison to last year’s maximum decibel levels of 123 dB, this year the maximum decibel level dropped to 113.5dB.
“Since firecrackers were manufactured at lower decibel levels, a joint inspection of firecrackers by Awaaz Foundation and the Maharashtra Pollution Control Board found that even at places where time-limit violations occurred, the decibel levels were lower,” Abdulali added.
Worli and Marine Drive were among places where noise levels ranged between 90 dB and 113.5 dB. Most other places in Mumbai witnessed a quieter Diwali.
At Marine Drive, the highest decibel levels of 111.7 dB and 113.5 dB were recorded after the deadline of 10 pm for bursting crackers. Whereas at Worli sea face, sporadic crackers mostly anars, sparklers and chakris were used.