A dry fog is considered to have water droplets less than 10 micron. This is usually only practical in enclosed areas as droplets of that size will evaporate very quickly. In open area's particularly with equipment which throws the fog over distance you want larger droplets eg 90 micron. A Fog Cannon is an example of a machine which throws fog/mist it over long distances.

This website has a useful discussion of dry fog based dust suppression as well:

http://cementamericas.com/mag/cement...sprayingdust/

Nicholas Marks

Wet Earth Dust Suppression

[email]nicholas@wetearth.com.au ■