I've done thousands of square feet of tile in my day, I can tell you that there are definitely some things to consider while grouting.
First, I'll just assume you're not mixing any thinset mortar or grout in the house. Always mix these outside..preferably with a mask on. It's also best to mix grout by hand instead of with a mixer because you won't introduce air bubbles.
Primary consideration should be given to the grout cleanup. Once you float all the grout into the seams and wet sponge the excess, be EXTREMELY careful when cleaning the hazy residue from the tile surface. To save time, many (including myself) wipe up the haze with dry rags and/or old clean towels. Don't do this! You'll create a fine, powdery haze in the room that has silica and other nasty things you don't want airborne and in your tank or sump. Although tedious, use a couple wet tile sponges and keep wiping the hazy excess off every half hour or so...rinsing them thoroughly in a bucket of fresh water after each of the two sides of the sponge are saturated with grout. Every time you finish a full pass of the room, rinse out the sponges in fresh water and dump the dirty water and start fresh in a half hour. You may have to do this 3 or four times before the haze doesn't appear anymore, but you can rest assured none of it got in your tank. It's probably a good idea to turn your skimmer and forced air heating and cooling off for the duration of this process as well. At the very least, close the registers in your floor to keep air flow at a minimum. When you're done. shopvac the the floor. Sweeping shouldn't be done anywhere close to the tank for a few days.
HTH
