If you use a sprayer: Just to be safe I would abide by their precautions. Also, I would rig a large fan in a window or door and have it blowing out. You then open a window in the house above and none of the paint mist will migrate upstairs and you will get your lungs enough fresh air. I would buy a canister ventilator (mask) with dual activated charcoal filters and a full body, hooded tyvek throwaway paint spraying suit (unless you want to end up with white hair).
Actually,... "I" wouldn't do any of this because I wouldn't use a sprayer. The "idea" of using a sprayer is usually much better than the actual experience. Return the sprayer to the store and buy rollers with broom handles and roll the walls etc. It will come out better and create far less mess and bother.