除尘领域怎么区分dust、smoke、mist和fume？

（2009年8月13号回答一网友的提问）

答：

刚好在《生态和环境词典》
（Dictionary of Ecology and Environment By L L Somani）中看到这些东西。

颗粒直径小于1um 的称为气溶胶 （aerosol)。
烟(smoke)：由直径小于1um 的固体和液体颗粒组成。
臭烟(fume)： 由直径小于1 um 固体颗粒组成
灰尘（dust): 当固体颗粒直径大于1um 时，通常称之为灰尘
雾(mist) : 悬浮于气体中的液体颗粒，其直径通常不大于100um

为避免翻译有误，原文抄录如下：
Particulate size: coarse dustparticulate larger than 10 um in diameter and fly ash composed of theimpurities remaining after coal is burned settle out of the quickly.Fume, dust, and smoke particles, ranging in size from under 1 up to10 um, travel farther, the distance covered depending mainly on thesize. Particles less than 1 um in diameter (generally referred toas aerosols) move aseasily and as far on wind or air current as gases do. Smokedescribes both solid and liquid particles under 1 um in diameter. Itcan be produced during all forms of combustion and in such processesas distillation, the removal of impurities from liquid by heatingthem to their boiling point and then condensing the vapours. Thedesignation “smoke”may include fume. Fumeindicates solid particles under 1 um in diameter that are formed asvapours condenor as chemical reactions take place. Fumes are emittedby many industrial processes, including smelting and refining. Dustis a more general term than fume. When solidparticulates are more than one micron in size, they are generallyreferred to as dust. Mistis made up of liquid particles up to 100 um in diameter. These may bereleased industrially in such operations as spraying and impregnatingor formed by the condensation of vapour in the atmosphere, or by theeffect of sunlight on automobile exhaust. As mist evaporates, moreconcentrated liquid aerosols are formed.

通常所说的灰尘(dust), 其直径都小于420 um。