Air pollution episode conditions due to Particulate which is primarily fallout from volcanic activity or windblown dust. Ambient Particulate control measures to be taken as appropriate in episode area.
Source:
Rule 340-206-8040 — Air pollution episode conditions due to Particulate which is primarily fallout from volcanic activity or windblown dust. Ambient Particulate control measures to be taken as appropriate in episode area., https://secure.sos.state.or.us/oard/view.action?ruleNumber=340-206-8040
.