What safety precautions should I follow when cleaning the inside of the printer?

Before cleaning the inside of the printer, turn off the power switch and unplug the printer from the AC power outlet, as there are high voltage electrodes inside. Do not use a vacuum cleaner to clean up scattered toner, as toner dust may ignite inside the vacuum cleaner and cause a fire — instead, use a dry, lint-free cloth. Do not use flammable substances or sprays to clean inside or outside the machine. (Page 2)