Air quality in the Chinese capital improved drastically on Thursday as the threeday red alert issued by the government came to an end at noon. The government claimed the improvement was the result of measures taken as part of the red-alert implementation. The reduction in pollutants in Beijing was dramatic with the China Environment Protection Bureau reporting an air quality index (AQI) of 37 at 9pm. The AQI was less than 100 for most of the day, after hovering around 300 on Wednesday. A cold burst and increased wind speed were believed to be the reasons behind the low pollution. The red alert helped to cut concentrations of PM2.5 by 10%, Cheng Shuiyuan, head of the College of Environmental and Energy Engineering at Beijing University of Technology told the Chinese media. The amount of vehicle exhaust had been halved due to traffic restrictions.