I've been following several threads that discuss edging and polishing tile using dry and wet methods. It cannot be stressed enough that you must protect your lungs, and the lungs of those around you, when grinding stone. Just a paper mask will not suffice, you need a dust and mist respirator (for example, 3M 8210).
Remember also that after wet polishing the slurry will eventually dry, allowing the silica to become airborne. If dry griinding at a minimum use a vacuum system with a HEPA filter. You should really have a dust collection system in place, at the very least a grinding booth.
If you are grinding and polishing in a shop that has a heat/air system, turn off the system prior to grinding and leave off until after full clean up. Your clothing will also be contaminated with dust so you may want to consider wearing "coveralls". Ideally, these coveralls should be washed after each wear, or at the end of a day of grinding.
If you are using silicon carbide grinding rocks don't ever use a rock that has been dropped. Unseen fractures in the rock can cause it to fly apart under the stress of grinding.
Sorry if I am stating the obvious here, but silicosis is a very serious health problem. As manager of a stone fabrication facility I battle the dust problem daily.