Randy Martin answers questions about air filter masks
The Logan Utah Herald Journal interview Randy Martin about the air pollution in Cache Valley recently. February 6, 2017 the newspaper article "What's up with that? Not all masks, respirators protect against PM2.5" was published.
Randy explains that PM2.5 pollution includes all particles smaller than 2.5 microns. Masks and respirators are manufacture for certain purposes. A person needs to view the filter ratings to get a mask that will filter particles smaller than 2.5 microns.
See the above article for the complete story.