Understanding and Dealing with the Silent Danger of PM 2.5

ภาพปกข่าว รู้จักPM 2.5 1

PM 2.5 refers to fine particulate matter, where “PM” stands for “Particulate Matter” or dust particles. The number 2.5 refers to the size of the particulate matter, which measures no more than 2.5 microns in diameter. To put this in perspective, 2.5 microns is about 1/25th the width of a human hair. This tiny size […]