How effective would this be to manage dust? After briefly trying out a diamond tip on a rock with a dremel I would like to pursue it as an occasional hobby, but want to avoid dust in the air.  

I can pick out a mask, but since this will be done at a hobby table in my bedroom, not a dedicated work area I want to stop the dust getting into the air, not just wear a great mask, because at some point the mask comes off and I do other stuff in the room like sleep!

I plan on working in a large open fronted plastic box with a hole on one side to fix a fan to create a cross current, and a hole on the other which will lead to an intended for floor air filter with a HEPA filter.  I will use a water dropper to keep the surface wet.

Is this insufficient, or is it overkill?  Or any better suggestions?

Thanks