According to Uzhydromet’s observations on the state of atmospheric air pollution, during the quarantine period (March 24 – April 06), there were no cases of exceeding the maximum permissible concentrations for determined pollutants in the air of Tashkent.
As Uzhydromet reports, the atmospheric air pollution index almost halved – from 4.15 to 2.5.
An indicator of atmospheric air pollution is the integrated Air Pollution Index (API), which is calculated by five priority polluting ingredients (dust, carbon monoxide, nitrogen dioxide, sulfur dioxide and ammonia). An API value of lower than 5 points corresponds to a reduced level of contamination.
The level of air pollution is considered low when API is between 0 and 4, increased when 5-6, high when 7-13, very high when API>14.
Compared to the beginning of the month, the maximum allowable concentration (MAC) decreased:
• dust from 0.16 to 0.14 mg/m3 (from 1.1 to 0.9 MAC);
• nitrogen dioxide – from 0.04 to 0.02 mg/m3 (from 1 to 0.5 MAC);
• carbon monoxide – from 2.6 to 2.2 mg/m3 (from 0.9 to 0.7 MAC);
and the content of sulfur dioxide and ammonia remained unchanged – 0.003 and 0.01 mg/m3, respectively (0.06 and 0.25 MAC).