Delhi’s air quality remains under ‘poor’ category on Saturday; AQI at 262

The air quality of Delhi on Saturday remained under the ‘poor’ category as per the System of Air Quality and Weather Forecasting And Research (SAFAR)-India. The Air Quality Index (AQI) stood at 262 on Saturday morning. With the Diwali festival around, the city's air quality has continued to deteriorate. Every year, Delhi's pollution level spikes up from October and lasts till the end of fall due to various reasons such as the burning of stubble, smog, etc.

On Friday as well, Delhi's AQI was under the poor category. An AQI between zero and 50 is considered good, 51 and 100 satisfactory, 101 and 200 moderate, 201 and 300 poor, 301 and 400 very poor, and 401 and 500 severe.

Now, in a bid to control pollution levels in the city, the Delhi government has announced to launch of the "Red Light on Gaadi off" campaign from October 28.

Under the campaign, first launched on October 16, 2020, to cut down vehicular pollution in the national capital, drivers are encouraged to switch off their vehicles while waiting for the traffic light to turn green.

Data from the Petroleum Conservation Research Association (PCRA) shows that if people switch off engines at traffic signals, pollution can be cut down by 13-20%.

According to government estimates, the transport sector accounts for 28% of the PM2.5 emissions in Delhi.

The vehicular contribution also makes up 80% of nitrogen oxides and carbon monoxide in Delhi's air.

Separately, in an analysis by the Centre for Science and Environment (CSE), Delhi's PM2.5 pollution during July-September remained lowest in 5 years.

There have been 45 rainy days in July, August, and September this year as compared to just 39 rainy days in the quarter last year.

"These six extra rainy days helped keep the seasonal average low despite total rainfall this monsoon having been just one-third of the previous monsoon," the CSE said.

These additional rainy days also pushed the regular start of bad air quality days further down in October, it said.

The PM2.5 average for the quarter stood at 38 microgram per cubic metre in 2021, 41 microgram per cubic metre in 2019 and 43 microgram per cubic metre in 2018.

The CSE had on Thursday said the average PM2.5 pollution in Delhi in the winter season has declined by about 20 per cent as compared to the pre-pandemic period.

The PM2.5 concentration for winter (October 1 to February 28) used to hover around 180-190 microgram per cubic metre before the pandemic. It has come down to 150-160 microgram per cubic metre since then, it said.

However, the seasonal average is still over 150% above the 24-hour standard (60 microgram per cubic metre) and almost four times the annual standard.