Open and close your door several times with the chain lock in place. Again, the door should open a maximum of 1-inch to provide utmost protection. If you have small children, have them open and close the door themselves to make sure they are able to successfully operate the lock. It is often necessary to purchase these separately. USE locking screws when installing the chain mount to the wall for added security.
Burglars often check under doormats, in flower pots, and over the door's ledge for hidden keys.
If you must have an extra key out for emergencies, leave it with a trusted neighbor or landlord. LOCK all doors which provide an outside to inside entryway point to your home. This includes patio doors, second-story doors, cellar doors, back doors, and garage doors. ADD extra lighting to the exterior of your home or turn on outside lights. Thieves do not commonly rob areas surrounded in bright light.