What is Fail-Safe and Fail-Secure?
Keyless access system components can be either fail-safe or fail-secure. These functions affect electromagnetic locks, electric strikes, panic hardware, and electromechanical locks differently. Understanding these terms is important to life safety and security.
Fail-Safe: Doors will be unlocked if power is disconnected or lost.
Fail-Secure: Doors will be locked if power is disconnected or lost.
These terms provide insight into the status of the key side (outside) of the door. All access systems are required to provide free egress from inside regardless of whether they are fail-safe or fail-secure.
Electric strikes
This hardware replaces a standard door strike to allow for electrically controlled access. Electric strikes are mounted in the door frame and its pair mounts in the inactive leaf or on a mullion. A spring-loaded keeper controls the latch bolt. When access is allowed, the keeper is free and the latch bolt can be pulled through the keeper, so the door can be opened. When the strike is secure, the keeper secures the latch bolt and prevents the door from being opened. In most cases, a key can be used to retract the latch bolt from the secure side of the door to allow access if a manual override is needed.
National Fire Protection Association (NFPA) 80, Standard for Fire Doors and Other Opening Protectives requires fail-secure electric locks on fire-rated doors. This does not impact a firefighter’s ability to gain entry using a key or access-control credential in the event of a fire or emergency.
There are significant security concerns with fail-safe hardware. Your building’s security should not be jeopardized every time there is a power outage. Fail-safe locks allow anyone, credentialed or not, to enter a building if there is a power loss. Avoid theft and unwelcome trespassers by using fail-secure protocols in your card access solution.
Electromechanical locks
A lockset that has been electrified is called an electromechanical lock. These devices can be controlled by a card reader or remote release.
A fail-secure electromechanical lock is secure and locked on the key side when there is no power to the lock. Power is applied to release the lock and the lever can then be turned to retract the latch.
Alternatively, a fail-safe electromechanical lockset is locked when power is applied. When power is removed, the lever can be turned to retract the latch. The lock is constantly powered so the lever on the key side remains locked. These are used for stairwell doors and provide re-entry into the building. During a fire alarm, the power is removed, which releases the lock and allows egress. The doors would also be unlocked during a power failure.
