CityNews – 3rd March 2020, with Chiang Mai’s AQI at 179, which ranks us as the world’s fourth most polluted city according to www.airvisual.com, authorities are stepping up to combat this crisis. With support from the Air force with fire fighting airplanes, fire spotting airplanes and survey airplanes, with widespread use of water sprinklers to douse the particles in urban and touristy