The Air Quality Index (AQI) in the national capital was recorded at 336 on Wednesday morning bringing the air quality under the 'very poor' category for the fourth day in a row and the third straight day this week.

As per the SAFAR-India, the city's AQI has been in the 'very poor' category since Sunday (309).

The AQI was recorded at 322 on Monday and 327 on Tuesday, as per the data provided by the System of Air Quality and Weather Forecasting and Research (SAFAR)-India.

Meanwhile, morning walkers of the national capital said that breathing is not as easy as it used to be in the summer months.

"It feels a bit uncomfortable to breathe while running due to pollution now as compared to in the summer months. I face congestion. We need to remain careful and take all precautions," said a morning walker near Mayur Vihar.

In the Delhi University area and Pusa, the quality of air was recorded as 'very poor' with AQI at 391 and 311, respectively at 7 am today.

The quality of air in the IIT Delhi region also remained in the very poor category with an AQI of 329. The quality of air at the Airport (T3) and Mathura Road was also in the very poor category, with an AQI of 339 and 362 respectively.

Meanwhile, Noida recorded an AQI of 391 (very poor) and Gurugram 323 (very poor).

Air Quality Index (AQI) is a tool for effective communication of air quality status to people in terms, which are easy to understand. It transforms complex air quality data of various pollutants into a single number (index value), nomenclature, and colour.

Last week, Delhi Environment Minister Gopal Rai said that a 15-point winter action plan is being implemented one by one to curb pollution.

"Delhi Chief Minister Arvind Kejriwal had earlier announced a 15-point winter action plan to curb the pollution caused by vehicles, biomass burning, dust, etc. Now this winter action plan is being implemented on the ground one by one to reduce pollution in the national capital," Rai had told ANI.

The Delhi Minister added that since one of the major causes of pollution is vehicles, they have started the 'Red Light on, Gaadi off' campaign on October 26."Now the data says that in AQI the level of particulate matter (PM) 10 is decreasing and that of PM2.5 is increasing. This means that pollution caused by vehicles and biomass burning is increasing. For this, the 'Red Light on, Gaadi off' campaign has been started," the Delhi minister had said.

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