A couple suggestions from experience with an allergy or two, and long experience working in particulate industrial atmospheres:
First, get a properly fitted double cartridge respirator with P3 cartridges. They aren't super cheap, but they last a good long while, and filter out anything you'd be dealing with. That, and a good pair of goggles, go a long way towards keeping any particulate out of your system. Just be careful taking them off, and clean them up when you do. Under sawdust service, they'll last for months.
Secondly, for those who have a hard time with anti-histamine drugs that make you drowsy (my issue: even the non-drowsy stuff puts me in slumber mode), or don't like drugs in general, try a couple grams of time-release vitamin C, and a gram of Citrus bioflavonoids (from the rinds of citrus fruits, found at health food stores).
I pretty much managed to kill my cedar and hay-fever allergies by taking these, usually daily in the summer. They pretty much do the same thing as anti-histamines, in a more natural fashion, by bolstering your own bodily defences against a histamine reaction. They seem to work well for me, and don't make you want to sleep.