Deadbolt lock definition
Deadbolt lock means a lock in a door operated from the exterior with a key and from the interior without a key, by knob or lever; which is mounted at a height not to exceed forty-eight inches (48") above the finished floor; which has a bolt which automatically locks into place when fully thrown; which has no springs to extend or retract it; and which has a bolt throw that is no less than one inch (1") in length.