What safety precautions should I take 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. Do not use a vacuum cleaner to clean up scattered toner, as this might cause the toner dust to ignite inside the vacuum cleaner. Instead, carefully clean the toner dust with a dry, lint-free cloth. Do not use flammable substances or sprays to clean the machine. (Page 2-3)