Expert virologist spells out main criteria for Covid-19 safe zone
THURSDAY, APRIL 23, 2020
Only a place that has been free from a Covid-19 case for 28 days can be considered a safe zone, Dr Yong Poovorawan, expert virologist at Chulalongkorn University, said.
Alarmingly high PM2.5 level found inside Chiang Mai air-pollution safe zone, but problem quickly res
MONDAY, APRIL 01, 2019
Chiang Mai’s air-pollution safe zone was not truly safe, a medical lecturer revealed on Monday, as the level of PM2.5 very fine particles was found to be very high even inside the designated area.