Delhi’s Air Quality Index has improved drastically over the last six days, ranging between 50 and 100, at the “satisfactory” level, the Hindustan Times reported on Tuesday. At 11 am on Tuesday, the AQI stood at 78.

On July 24, the AQI stood at 164. It has remained below 100 since July 25. On July 29, the Air Quality Index stood at 65.

An Air Quality Index 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”.

The Central Pollution Control Board said on Monday that the main pollutants were carbon monoxide and PM10 – particulate matter in the air that is smaller than 10 microns. The board’s estimate was based on data received from 33 monitoring stations.

“The air quality has improved to ‘satisfactory’ levels because of the intermittent rains and winds,” an unidentified senior official of the Central Pollution Control Board said. “The dust particles have all been washed away.”

The air quality in the national Capital hovers in the “moderate” and “poor” categories in the summer, and in winter it moves down to “very poor” and “severe”. During Diwali, the AQI shows the poorest readings.

In 2017, a Graded Response Action Plan was put into action to combat air pollution following a Supreme Court directive. Last year, the board told the Supreme Court that citizens mostly complained about construction waste being improperly dumped or left uncovered.

The monsoon deficiency in Delhi has reduced to 30%, the Hindustan Times reported. The India Meteorological Department has forecast more rain this week. The maximum temperature on Monday was recorded at 36°C, two degrees above normal, while the minimum temperature was 27.4°C.