Samuel Smith

pm2.5 concentration readings of 190+ ug/m3 is closer to the truth. That's AQI of 240+ Readings taken in the morning.

And fine the hostel for not filing a TM30

Most sites such as airvisual.com & aqicn.org show AQI on the map, not pm2.5 concentration. Different things. Can calculate AQI from concentration here https://airnow.gov/index.cfm?action=airnow.calculator pm2.5 concentration of 59 = AQI 153. If you have your own pm2.5 meter, you can convert to AQI. A "safe" AQI of 50 = pm2.5 concentration of 12ug/m3! Rarely seen in Chiang Mai!

"A reading of 59 micrograms was recorded " Was this recorded in a filtered room? pm2.5 readings of over 100 are the norm, the last couple of weeks!

Which helpline did you ring?

+1 for french press. So simple & easy to use, for great tasting coffee