Power Lost, Door Open or Locked? Understanding Fail Safe and Fail Secure Locks
October 16, 2026
The two fundamental components at an access-controlled door are the credential reader and the electrified lock. One authorizes entry and the other allows it to occur. There are two basic types of electrified locks from a safety standpoint: (1) Fail Safe and (2) Fail Secure. Fail safe locks can be opened for exiting when power is not on and fail secure locks cannot be opened for exiting when power is off.
Some locks by their very nature are fail safe, such as magnetic locks and electrified panic hardware. As a magnetic lock requires electricity to hold secure, when power is lost the lock unlocks. Electrified panic hardware uses the principle of “Free Mechanical Egress”; i.e., regardless of the state of the lock, when one pushes on the panic bar, the door opens. Other locks can be found in both types, such as electrified mortise locks, electrified cylinder locks, and electrified dead bolts.