I have facial hair most of the year. And I wear glasses. Those are the two things that make or break the comfort and the effectivness of a dust mask for me.
But since finding the Lee Valley dust mask my issues have disappeared. The body of the mask is soft and very flexible rubber. This conforms over my beard pretty darned well.
It's not absolutely perfect, but given that it's going over a layer of bushy beard it's actually good.
The second knock I have with almost every other mask that I've worn is that exhale air escapes over my nose, resulting in fogged up glasses. AHA! That's also a thing of the past. This mask conforms comfortably, yet tightly over the bridge of my nose and so I don't blind myself as I breathe. HALLELULIA!!!
The business end of the mask is a flap gasket and large pad filter. It's NIOSH rated at N99, making it fine for dust particles and NOT for filtering chemicals. (If you're intending to spray, look for a dual-cartridge respirator instead.)
I've worn this mask more than any other solution in my shop. FINALLY there's a dust mask that I'll actually wear. And I do, with much micro fanfare from my lungs and sinuses!
It's also fun that you sound quite a bit like Darth Vader when you wear this mask. I'll leave it to others to chase the kids around the house and declaring that you're their father!
Replacement dust filters are just a couple of dollars, so maintaining this dust mask in good condition doesn't set you back much, either.
Overall, if you have facial hair or wear glasses like I do there's finally a solution for you!