Diffusion: Really Fine particles measuring beneath 0.one micron get bounced all-around randomly and are slowed by their interactions with atmospheric atoms and molecules. They at some point drift or get bounced into a filter fiber, whereupon (over again) they adhere in a process known as diffusion. กลิ่นไม่พึงประสงค์ เช่น ควันบุหรี่ น้ำเน่าริมทาง waiting for link from Social Network Posts