Delhi's air quality fell in the 'poor' category Thursday as light showers brought down the pollution level slightly in the national capital, authorities said. The overall air quality index (AQI) was recorded at 237 which falls in the 'poor' category, according to data by the Central Pollution Control Board. Two areas of the city recorded 'very poor' air quality, 26 areas recorded\u00a0'poor' air quality while seven areas recorded 'moderate' air quality, it said. On Thursday, the PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) level was recorded at 105, while the PM10 (particles in the air with a diameter of less than 10 micrometres) was recorded at 191 in Delhi. READ ALSO |\u00a0Jammu and Kashmir: After fresh snowfall, weather likely to improve today An AQI between 0 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". Delhi's air quality has been oscillating between 'very poor' and 'severe' after Diwali due to explosion of fire crackers. But after rains since Tuesday, the air quality has significantly improved, but fell in the 'poor' category. According to the Indian Institute of Tropical Meteorology, the PM2.5 concentration will improve in the next two days. "The air quality is likely to improve in the next two days, but will remain in 'poor' and 'very poor' categories in Delhi NCR. Also, the impact of biomass burning in north west India is marginal over Delhi,"