The photo that ET provided is actually showing a "half mask". A full face respirator would look like the ones that firemen wear with an air bottle. There are full face respirators available that fit up to dust or organic vapor cartridges, but i have not seen any in the hardware stores. Look for a safety products supply house that carries industrial type safety items. Also, there are provisions in some of these full face masks to insert prescription lenses.

I spent 40 years in the chemical industry and have dealt with sensitizers and plenty of toxic stuff. I would have considered the dust from fully cured epoxy to be inert. Either it's not inert or you are very highly sensitive to it. The problem with sensitizers is that you don't know you're highly sensitive until it's too late. Exposure via the eyes is one pathway that should be protected.
Avoiding the dust (and vapors) via the ventilation systems is absolutely the first choice of control.