Owing to better wind speed on Tuesday, city residents heaved a sigh of relief as the air quality, which had been marked ‘severe’ over the last few days, showed significant improvement.

The air quality index (AQI) was recorded at 355 on Tuesday, as per data provided by the Central Pollution Control Board (CPCB). The AQI on the day marked a significant drop from Monday’s 466.

Experts attributed the improvement of air quality to the better wind speed of 1.03 m/s on Tuesday, up from 0.73 m/s on Monday.

Over the last week, the city’s air quality remained in the ‘severe’ zone, despite measures adopted by the district administration under the Graded Response Action Plan (GRAP).

Experts were of opinion that there could be smog-free days in store for the city going forward, as rain and better wind speed is likely to disperse pollutants from the region.

Although dense smog shrouded the city during the morning and evening hours on Tuesday, there was some respite for residents in between as warm sunshine and better wind speed boosted air quality.

“Wind speed and direction plays an important role in clearing out pollutants. Once the region gets better wind speed for a few days, the situation will improve. Also, the ban on all polluting industries and dust generating units in the region has also contributed to the air quality to getting better,” JB Sharma, regional officer, Haryana State Pollution Control Board (HSPCB), said.

Read I Air pollution: Gurgaon shuts down polluting factories till November 14

According to the India Meteorological Department (IMD), the city is likely to get some rain on Wednesday and Thursday.

The air quality index is an indicator of the air pollution from the levels of three pollutants that includes NO2, PM 10 and PM 2.5. The index indicates air quality as ‘good’ if it is in the range of 0-100, moderate if between 101 and 200 and poor if between 201 and 300.

The index for individual pollutants at a monitoring location are calculated as per its 24-hour average concentration value (8-hour cycle in case of CO and Ozone) and health breakpoint concentration range.

Date --------------------Air Quailty Index

14- Nov-------------------355


12 Nov--------------------460

11 Nov---------------------436

10 Nov---------------------485

09 Nov---------------------494

08 Nov---------------------459