Fail safe vs fail secure
We see both on almost every campus, and it gets confusing. What each one does when the power goes out, and which one a fire door needs.
Here is an article from I Dig Hardware that explains fail safe and fail secure hardware on doors in detail. It’s an interesting read about the latching arrangements we see on pretty much all of our campuses.
I know this gets confusing sometimes — at least it does for me — so I like to dig in and give myself a refresher from time to time.
The words describe the LOCK, not the person: fail safe unlocks when power is lost, fail secure stays locked. Either way, people inside must still be able to get out.
What the code says
Fail safe
Needs power to stay locked. Cut the power — a fire alarm release, an outage — and the door unlocks. Magnetic locks work this way by nature.
Fail secure
Needs power to unlock. Cut the power and the door stays locked from the outside. Free egress from the inside is still required, normally through the mechanical lever or exit device.
On a fire door
A fire door has to positively latch, power or no power. That is why an electric strike on a fire door is fail secure: the latch must stay engaged in a fire. A fail-safe strike would let the door swing free and stop protecting the opening.
Read the full explainer
Our article walks through stairwell re-entry, access control on egress doors and what to check on each.
Practice drill: check it on your next round
- Electric strike on a rated door? It should be fail secure and listed for fire doors.
- Mag lock or access control on an egress door: does it release on fire alarm and on loss of power?
- Can you get out from the inside with one motion, without a key or card?
Sources and further reading
Section numbers are from NFPA 80 (2013) and NFPA 101 (2012), the editions CMS and The Joint Commission enforce for hospitals. Check the edition your authority having jurisdiction has adopted.