The link is to a Washington State Department of Health PDF concerning wildfire smoke and face masks - I found it helpfully in selecting a suitably effective particulate respirator mask for dealing with all this dang smoke - I’m using a 3M N95 particulate respirator mask for longer outdoor exposures - It works well - I don’t know if the local hardware stores or other local retail outlets still have the N95 and (or) the N100 particulate respirator masks in stock - They’re still available from Amazon, but it may take a couple of days for delivery.  
http://www.doh.wa.gov/Portals/1/Documents/Pubs/334-353.pdf