City’s air quality turns ‘poor’ after 8 months: SAFAR

The air quality index (AQI) of the city entered the ‘poor category’ on Friday, first time since March 24, according to the System of Air Quality Weather Forecasting

The air quality index (AQI) of the city entered the ‘poor category’ on Friday, first time since March 24, according to the System of Air Quality Weather Forecasting and Research (SAFAR). Earlier on Thursday, data recorded by Central Pollution Control Board (CPCB) had shown that AQI was already in ‘poor’ category, a first for this season, even as SAFAR data had recorded ‘moderate’ air pollution levels.

HT Image

The AQI on Friday was 201 during the day, and fell to 194 by the evening.

SAFAR and CPCB categorise AQI for pollutants in the 0-50 range as good; 51-100 as satisfactory; 101-200 as moderate; 201-300 as poor; 301-400 as very poor and above 400 as severe.

AQI data is recorded for PM2.5 pollutant — particulate matter of 2.5-micron size which can easily enter lungs and cause ailments — from 10 stations across Mumbai. Last time the AQI in Mumbai was ‘poor’ as per SAFAR’s data was on March 24, at 254.

Meanwhile, CPCB recorded an AQI of 205 (poor) based on monitoring across eight stations on Friday.

Researchers said low temperatures, moisture and calm winds — weather conditions similar to Thursday — had allowed the formation of a boundary layer close to the surface leading to hazy conditions on Friday. Location-wise data from SAFAR showed that Bandra Kurla Complex was the most polluted site with ‘very poor’ AQI at 304, followed by Malad at 274, Mazagaon at 260, Navi Mumbai at 239, and Borivli 201.

The concentration of PM2.5 was 85 microgrammes per cubic metre (µg/m3) on Friday against the safe limit of 60 µg/m3, and concentration for PM10 (larger coarser particles) was 177 µg/m3 against the safe limit of 100 µg/m3.

An AQI of 186 (moderate) has been predicted for Saturday.