Keeping the way out usable: egress doors, locks and obstructions
A clear corridor is not signed off once. One motion to open, doors that unlock before the horns, and the delayed egress condition most often broken.
The way out of a building only counts if people can actually use it. NFPA 101 Chapter 7 sets out what a usable means of egress looks like, and NFPA 72 Chapter 21 sets out how electrically locked doors behave when the fire alarm system is involved.
Clear whenever the building is occupied
The means of egress is kept free of obstruction at all times the building is occupied (NFPA 101 Chapter 7, NFPA 1 Chapter 14). It is not a design feature that gets signed off once.
One motion, no key
A door in the means of egress opens from the egress side with one motion, without a key, a tool or any special knowledge, whenever the building is occupied (NFPA 101 Chapter 7).
From the field
Thumb turns above a lever, surface bolts and hasps all fail this. So does a sign asking people to turn two things.
Electrically locked doors and the fire alarm
Electrically locked doors in a required means of egress unlock in the direction of egress where the building code, the life safety code or the AHJ requires it. Whether a given door needs it comes from those documents. NFPA 72 Chapter 21 only sets out how the unlocking has to behave, so do not cite NFPA 72 as the reason a door must be tied to the fire alarm system.
| Question | What NFPA 72 Chapter 21 expects |
|---|---|
| When do the doors unlock? | Before, or at the same moment as, the public mode notification appliances in the areas they serve. Never after. |
| When do they relock? | Only once the fire alarm condition is manually reset. Not on silence, not on a timer, not when the initiating device restores. |
| Can panel batteries hold them locked? | Only if the panel has the circuitry and secondary capacity to unlock them within 10 minutes of losing primary power. |
| What if the locks have their own supply? | Locks on an independent supply dedicated to lock and access control power, which release when that supply fails, are outside the battery rule entirely. |
A compliant arrangement can legitimately hold doors locked for a period after primary power fails. Find out which supply feeds the locks before judging it.
From the field
Verify the unlock from an actual initiating device, not from a panel test switch, because the programming path can differ. Doors that relock on silence rather than on reset are a real hazard and a common programming error. Test the behavior on battery rather than assuming either way.
Delayed egress and sensor release locks
Both are allowed only where the occupancy chapter permits them, so the occupancy chapter decides first (NFPA 101 Chapter 7). Delayed egress then carries a long list of conditions:
- The building is sprinklered or has detection, and the delay drops when a sprinkler or detector operates and when lock power is lost.
- An irreversible release within 15 seconds, or 30 with AHJ approval, under a force of no more than 15 lbf applied for no more than 3 seconds.
- An audible signal when the release starts.
- Rearming by manual means only.
- A specific sign at the door, emergency lighting on the egress side, and hardware listed to UL 294.
Rearming by manual means only is the condition most often broken, by a system that re-arms itself on a timer. The sign wording is set word for word and differs depending on which way the door swings.
From the field
Access control hardware fitted during a tenant fit out without anyone checking whether the occupancy permits it is very common.
Keep reading
Strobe mounting height and candela: how NFPA 72 sizes visible notification
Measure the lens, size the room correctly, and never drop a strobe below 80 inches without redoing the coverage.
Fire doors: self closing, latching and what actually voids the label
A door that closes but does not latch has lost its rating. Not every hole drilled on site has, and the listing laboratory is who decides.
Waterflow and supervisory signals from the sprinkler system
The 90 seconds is the device, not the horns. What the waterflow and supervisory devices have to do, and how many go on one circuit.
Changed the system? What NFPA 72 says you retest
One added horn is a one device test. One added horn plus a programming change is not. How the scope of reacceptance follows what changed.
Kitchen hood suppression systems: the hazard, the system and the inspection
The grease decides whether a hood needs a system. What happens when it discharges, where the pull goes, and the four changes that force an upgrade.
Secondary power and standby batteries: what NFPA 72 asks of them
24 hours quiet, then the alarm. Why the battery calculation matters more than a load test, and why an undated battery is the installer's problem.