NFPA 72 2010 - 21.9 Electrically Locked Doors

[LGreene]

I need some help from fire alarm experts on a door-related question. I'm sorry for the long and detailed post - bear with me.

In the editions of NFPA 72 prior to the 2010, it wasn't clear that doors with access control had to unlock in the direction of egress upon initiation of the fire alarm. The code just said that the doors had to unlock, which some AHJs were interpreting to mean that any door with a card reader had to be completely unlocked upon fire alarm.

The 2010 edition clarifies the requirement:

"21.9.1 Any device or system intended to electrically lock a required means of egress door in the direction of egress shall be connected to the fire alarm system serving the protected premises.

21.9.2* Electrically locked doors in a required means of egress shall unlock in the direction of egress as prescribed by other laws, codes, and governing standards."

This requirement would typically apply to doors with electromagnetic locks (access-controlled egress doors) and delayed egress locks (special locking arrangements). One of the gray areas surrounding these two types of locks is whether battery back-up or another type of back-up power can be used to keep the doors locked during a power failure. The IBC says that these types of locks must "unlock upon loss of power controlling the lock or lock mechanism."

While I was researching the NFPA 72 requirements, I was reading the NFPA 72 Report on Proposals for the 2002 edition regarding 6.15.7.3 which refers to fire alarm systems that operate on battery backup.

"SUBSTANTIATION: This proposal is based on the work of a pre-ROP task group of the TC of Protected Premises Fire Alarm Systems. The changes will not allow batteries to be used to lock exit doors when the secondary power supply for the fire alarm system is provided exclusively by batteries. Secondary power supplies that utilize generators may opt to continue to keep the doors in the locked position. This change reflects the change in the permissible secondary power supplies from the previous edition."

This is the 2010 language (it moved to a different section):

"21.9.3* For all means of egress doors connected in accordance with 21.9.1, and where batteries are used in accordance with 10.5.6.1.1(1) as the secondary power supply, the batteries shall not be utilized to maintain these doors in the locked condition, unless the fire alarm control unit is arranged with circuitry and sufficient secondary power to ensure the exits will unlock within 10 minutes of loss of primary power."

And finally, here are is my question:

I interpret all of this to mean that a mag-lock or delayed egress lock can not have battery back-up in the lock power supply. If the fire alarm runs on battery back-up, the lock can't stay locked for more than 10 minutes. If the fire alarm runs on a back-up generator, the lock could also run on the back-up generator and function normally. Agree? Disagree? Other thoughts?

 

[cda]

OK how did you get lost in the electrical forum

mybe ask to be bumped to commercial building code one door up

Boy you seem to know thee code/ standards better then alot of people

been reading that book and some reason that section never jumped out and hit me.

My response is start with the base building and fire code to see what they require, prior to jumping to 72.

we have our own gudielines on what is required based on the I codes

 

[peach]

The IBC requires the doors open in the direction of egress.

Mag locks release upon activation of the fire alarm. There are no locks in either direction. No pass cards.. no pass keys.. no delayed locks (well except in I occupancies)..

the idea is to get the hell out of the building.

 

[beach]

So, if a door isn't required to swing in the direction of egress unless the occupant load is over 50 or more per the IBC (unless it's an H occup.) does it now have to swing in the direction of egress if it has electrically locked doors? That's pretty interesting.........

I'm pretty sure you can't have a battery backup for the lock if the power fails per IBC 1008.1.4.4 #2

 

[cda]

Not sure if it meets code but the systems I have seen with battery backup. Continue to work normally as designed and Still allow get out of the building

 

[LGreene]

I think the intent of the IBC and NFPA 72 was that the doors would need to unlock in the direction of egress, but some AHJs have required every single door with a card reader to be unlocked in both directions on fire alarm. Many doors with card readers allow free egress all the time and don't need to change state on fire alarm. Doors that are required to unlock on fire alarm (like doors with delayed egress locks) only need to allow egress - they shouldn't have to allow free access as well unless it's a stairwell reentry situation. The change to NFPA 72 clarifies that pretty well, I think.

Beach - I don't think the doors need to swing in the direction of egress just because they have electrified locks - they just need to unlock to allow egress.

I'm still thinking battery backup is a no-no but generator power is ok.

 

[cda]

one reason we require the doors to unlock is so the firefighters can get in the building, we have some buildings that have some type of security device on every exterior door.

also, my boss started requireing a knox device to release the locks in case the fire alarm has not activated

 

[beach]

21.9.2* Electrically locked doors in a required means of egress shall unlock in the direction of egress as prescribed by other laws, codes, and governing standards."[/i]]

LGreene - I must have read it wrong, I thought you had it in bold for that reason....... I thought maybe I was missing something! To clarify, I can have an egress door that electrically locks, open in (not swing in the direction of egress) when allowed by code (under 50 occupants)?

sorry for going off track.......

I think your right regarding no battery backup but ok for generators

(I think Peach was thinking magnetic hold open devices?)

 

[cda]

are you mixing bbq sauce and mustard??

if you are talking requirements from NFPA 72 and says batteries cannot ne used, I would agree that no the batteries for the fire alarm panel cannot be used to power magnetic locks, or similar locking devices.

http://www.vonduprin.com/pdf/Security.pdf

The PS873 can be ordered with three

standard options: Key lock secures

the cover to eliminate tampering and

provides safety; Battery backup provides

two hours backup power at full load

during a A.C. power failure; Fire Alarm

provides input for a normally closed

fire alarm contact. When the fire alarm

contact is “open”, power to locks or

other component is removed. Restoring

power is field selectable for automatic

or manual.

Eight standard

 

[beach]

Fail Safe — FS

FS — FAIL-SAFE electric strikes require

power to be applied to lock the strike lip.

On loss of power, the strike is unlocked.

Building codes prohibit the use of

fail-safe strikes on labeled openings.

Field convertible with parts.

​

That quote is from the link you supplied........ I'm getting even more confused!! BBQ sauce and Mustard? possibly.........

Is this correct?:

The lock gets power from the building power source, if the power goes out, the the generator kicks in keeping the door locked, if the generator quits, the internal battery from the locking unit keeps the door latched, if the building goes into alarm, the door has to unlatch via the alarm panel. However, the battery from the alarm system cannot supply power to the door latch? AND if the battery from the locking unit fails, the lock has to unlatch......

 

[cda]

Beach

that is my take

clear as ??????????

 

[beach]

Actually, it now makes sense to me! Thanks CDA!

 

[cda]

Beach

Glad you finaly got your head out of the sand, you need to stay away from the beach!!!!!!!!!

Go to the moutains where you can think a little clearer!!!!!!!

 

[beach]

hahaha..... I lived in the mountains for five years, I still prefer the beach with my head stuck in the sand!!! (but it's only an hour and a half drive to the ski resorts.....)

 

[LGreene]

CDA: one reason we require the doors to unlock is so the firefighters can get in the building

I don't know of a code requirement for this, other than local fire department requirements. This could be a major security problem if all you had to do to unlock the building was pull the fire alarm, no? I know most of us are in the life safety business, not the security business, but I'd like to know if someone has seen the requirement for automatic firefighter access in a code. We typically have Knox boxes.

Beach: I thought you had it in bold for that reason

I had it in bold because it was a change in the 2010 edition of NFPA 72. Before it said "unlock" which could be interpreted a couple of different ways. Now it's clear that the doors have to unlock so people can get out, not necessarily to allow people/firefighters back in.

Beach: To clarify, I can have an egress door that electrically locks, open in (not swing in the direction of egress) when allowed by code (under 50 occupants)?

There are only a couple of applications that allow the doors to be locked, and unlock upon fire alarm. One example is with delayed egress locks which unlock after 15 seconds when someone tries to open the door. When the fire alarm is sounding, the doors unlock immediately. Access-controlled egress doors (mag-locks) are another example, although they're required to have motion sensors and push buttons to unlock them so in my opinion they're not restricting egress. It's not acceptable to have another type of lock that only allows egress on fire alarm, no matter what the occupant load, except for detention, etc.

CDA: Battery backup provides two hours backup power at full load during a A.C. power failure; Fire Alarm provides input for a normally closed fire alarm contact.

You can definitely buy a lock power supply that has battery backup for the locks and a fire alarm contact which typically cuts power on fire alarm. Most code officials in our area won't allow battery backup in the lock power supply when it's a delayed egress lock or mag-lock because if something goes wrong with the fire alarm contact, the batteries could potentially keep the door locked.

Beach: The lock gets power from the building power source, if the power goes out, the the generator kicks in keeping the door locked, if the generator quits, the internal battery from the locking unit keeps the door latched, if the building goes into alarm, the door has to unlatch via the alarm panel. However, the battery from the alarm system cannot supply power to the door latch? AND if the battery from the locking unit fails, the lock has to unlatch......

Usually when there's battery backup in the lock power supply, the lock is not also connected to the generator. If the battery from the alarm system isn't allowed to power the lock, I think it would make sense to say that a door that has to unlock upon fire alarm can't be powered on battery backup in the lock power supply, but can be powered by the generator since the fire alarm would also be powered by the generator.

I need to go take a nap now. Thank you for your discussion!!

 

[Markl_AHC]

Generator will take 5-10 seconds to get online. Without battery backup, no lock power or power to devices connected to that PS. F/A contact release and battery backup are separate functions. Both can co-exist when applied properly to have a code-compliant opening.

To answer the OP, if no generator for F/A system, there needs to be a timing circuit which unlocks the exits after primary power is lost for 10 mins. I would see that as part of the F/A system which would open all F/A contacts after 10 mins.