Since the end of last year (end of 2018), Thailand (Especially in Bangkok) has a wide awareness of air quality Has detected that PM values exceed the standard safety in many areas of Bangkok. For the average person, knowing the PM 2.5 level at the current position in real-time is difficult. Most people know the level of PM 2.5 from mobile apps only, which is not real-time and does not match the location, because in Bangkok there is little air quality measurement station. (In some areas of Bangkok, there is no air quality measurement station at all), so I try to create my own portable PM 2.5 meter.
use double tape to stick it together