Fail-Safe vs Fail-Secure Locks and Fire-Code Egress
A fail-safe lock unlocks when power is lost. A fail-secure lock stays locked when power is lost. Every access-controlled door in your building must be set to the correct mode — because the wrong choice on an exit door traps people during an emergency, and the wrong choice on a server room leaves sensitive equipment exposed during an outage. Here is how fire and building codes decide which mode belongs on which door, and what California inspectors look for.
Fail-safe vs fail-secure at a glance
| Fail-Safe | Fail-Secure | |
|---|---|---|
| On power loss | Unlocks | Stays locked |
| Requires power to | Stay locked | Unlock |
| Used on | Exit paths, stairwells, fire doors | Server rooms, storage, exterior entry, vaults |
| Primary goal | Let people out in any emergency | Keep the area secured even without power |
| Examples | Maglock on lobby exit, fail-safe strike on stairwell | Fail-secure strike on IT closet, pharmacy storage |
What is a fail-safe lock?
A fail-safe lock requires continuous power to remain locked. Remove the power — through an outage, a tripped breaker, a fire alarm signal, or a cut wire — and the lock releases immediately.
This makes fail-safe the only acceptable mode for any door on an egress path: building exits, stairwell doors, and corridors that lead to the outside. People must be able to leave in an emergency without any action beyond pushing the door. If the fire alarm sounds and the power stays on, the fire alarm panel must send a signal to cut power to the lock and release the door.
Magnetic locks are fail-safe by design — they hold only while energized. An electric strike can be ordered in fail-safe or fail-secure configuration; the wiring and internal spring differ between models, so you cannot change one to the other in the field.
What is a fail-secure lock?
A fail-secure lock requires power to unlock. Cut the power and it stays locked. A dead battery, a tripped breaker, or a fire alarm that does not release power to this particular circuit leaves the door locked.
This is the correct mode for rooms where the goal is protecting assets rather than allowing egress: server rooms, pharmaceutical storage, cash rooms, records archives, and most exterior entry doors where unauthorized outside access is the primary threat.
Note that a fail-secure lock on a purely interior door (with no egress role) is legal. But a fail-secure lock on a corridor or stairwell used for exit is a code violation and a life-safety hazard.
What California fire code requires on exit doors
California enforces the California Building Code (CBC) and the California Fire Code (CFC), both of which are adopted from the International Building Code (IBC) and NFPA 101 with amendments. The critical egress provisions:
Free egress requirement (NFPA 101 Section 7.2.1.5 / CBC Section 1010): Doors on exit paths must be operable from the inside with one motion, without a key, tool, special knowledge, or effort. Any locking device that requires more than single-motion release is prohibited on an exit.
Delayed egress exception (NFPA 101 Section 7.2.1.6.1 / CBC 1010.1.9.8): In certain occupancies (not high-hazard), an alarm-actuated delayed release of up to 15 seconds (or 30 seconds in some low-hazard uses) is permitted, provided:
- The building is sprinklered or has a fire detection system.
- Failure of the power supply, fire alarm system, or sprinkler system causes immediate release.
- A sign reads “PUSH UNTIL ALARM SOUNDS — DOOR CAN BE OPENED IN 15 SECONDS.”
This delayed-egress lock is common on emergency exits at retail stores where theft prevention is a concern. It is not a generic workaround — it requires an alarm interface and compliant signage.
Magnetic lock egress requirements (CBC 1010.1.9.9 / IBC 1010.1.9.9): A maglock on an egress door requires all three of the following:
- A sensor that detects an approaching occupant and releases the maglock before they reach the door (passive IR or similar).
- A manual release device on the egress side (push button or touch sensor) within 5 feet of the door.
- Automatic release upon fire-alarm activation.
Missing any one of these fails inspection and creates liability.
Request-to-exit sensor types and selection
The request-to-exit (REX) sensor lets occupants leave from the secure side without presenting a credential. Sensor type matters more than most installers admit:
| REX Type | How it works | Best for | Watch out for |
|---|---|---|---|
| Passive infrared (PIR) | Detects body heat movement | Standard interior doors | Slow-moving or small occupants may not trigger |
| Microwave | Detects movement through walls/glass | Doors with glass sidelites | Can trigger through walls, causing false releases |
| Push button | Manual button press | Areas needing deliberate exit action | Not ADA compliant without appropriate reach range |
| Dual-technology (PIR + microwave) | Both sensors must agree | High-security interior doors | Higher cost; reduces false trips |
On a door with a glass sidelite next to it, a microwave REX will frequently trip when someone walks past the adjacent hallway. PIR or dual-tech is the right choice there.
Fire alarm interface requirements
The connection between the fire alarm panel and your access control power supply is not optional — it is a code requirement on any magnetically locked egress door.
The typical wiring path:
- A normally-closed dry contact relay on the fire alarm panel connects to the access control power supply.
- When the fire alarm activates, the relay opens, cutting power to the magnetically locked door(s) and releasing them.
- The connection must be supervised — meaning the system generates a fault if the wire is cut or disconnected. An unsupervised connection can be defeated by simply cutting the wire.
California Fire Code Section 907.3 and related provisions require supervised connections on life-safety systems. Your access control installer and your fire alarm contractor must coordinate this interface; it should be documented in your fire system as-built drawings.
Which doors get which mode — a practical guide
| Door | Correct mode | Reason |
|---|---|---|
| Building main exit to outside | Fail-safe | Primary egress |
| Stairwell exit doors | Fail-safe | Egress path |
| Suite entry from corridor | Fail-secure (usually) | No egress role if corridor has other exits |
| Server room | Fail-secure | Asset protection; no egress role |
| Pharmacy / medication room | Fail-secure | Controlled substance compliance |
| Cash room / safe room | Fail-secure | Asset protection |
| Emergency exit (secondary) | Fail-safe with REX and fire-alarm tie-in | Egress; rarely used in normal operation |
| Parking garage exit gate | Fail-safe | Egress for vehicles and pedestrians |
When a door serves a dual purpose (entry and egress), egress takes priority: the inside is always free egress, and fail-safe is the correct mode.
What fire inspectors check
Orange County fire inspectors look for these items on access-controlled doors during plan check and field inspection:
- Fail-safe mode verified on all egress doors (inspector may manually cut power to test).
- REX sensor present and functional (inspector will walk toward the door to trigger it).
- Fire-alarm interface documented and supervised.
- Compliant signage on delayed-egress doors.
- Single-motion egress verified (no two-step releases).
- Panic hardware (if required by occupancy load) integrated and tested.
A failed inspection means the building cannot receive its Certificate of Occupancy, and a re-inspection fee is charged. Getting this right in design avoids both the delay and the expense.
Panic hardware and access control integration
In occupancies with more than 49 people using a door (NFPA 101 Table 7.2.1.2.1, CBC Section 1010.1.10), the exit must have panic hardware — a push bar that releases the latch with a single horizontal motion.
Modern panic devices from Allegion (Von Duprin) and ASSA ABLOY (Sargent, Yale) can be ordered with an electric latch retraction (ELR) option: an electric signal from the access control system retracts the latch, and the panic bar allows free exit as usual. This integrates access control monitoring (who exited, when) with required panic egress hardware.
We install and integrate panic bars and exit devices as part of the access control system design so every door is both code-legal and electronically monitored.
Frequently Asked Questions
What is the difference between fail-safe and fail-secure? Fail-safe unlocks when power is cut; fail-secure stays locked. Exit doors use fail-safe so people can always leave. Secure rooms use fail-secure to stay protected during outages.
Do access-controlled exit doors have to release in a fire? Yes. California Building Code and NFPA 101 require free egress on all exit paths. Maglocks on exits must have a fire-alarm tie-in that releases the door when the alarm activates.
Are magnetic locks fail-safe or fail-secure? All magnetic locks are fail-safe by nature — they hold only while energized, so any power loss releases the door. Electric strikes can be either, depending on the model selected.
What is delayed egress and when is it allowed? A code-compliant delayed-egress lock holds for 15 seconds after someone pushes to exit, with an alarm sounding. It is allowed in certain occupancies with sprinklers or fire detection and requires specific signage. It is not a general substitute for proper exit hardware.
What happens if the fire alarm interface is not wired? A magnetically locked egress door that does not release on fire alarm is a code violation and a life-safety failure. The inspector will require correction before issuing occupancy, and the building owner may face liability if an injury occurs.
Passing fire inspection starts with the right lock behavior on every door, designed from the beginning — not corrected after a failed inspection. Golden Locks sets fail-safe and fail-secure correctly as part of commercial access control in Orange County. Call (714) 841-0141.
By Omar, Licensed Locksmith and Access Control Specialist — CA Lic. #LCO4446 / #988707.