Mike, There is a difference between a smoke alarm (found in residential applications) and a smoke detector which is part of a commercial fire alarm system. Smoke alarms are interconnected combination smoke detectors with a noise maker. Some also will include the CO detector now required outside the bedroom. Please do not add to the confusion by refering to residential smoke alarms as smoke detectors. They are so much more.

The NEC is beginning to institute changes/modifications that are not wise or safety related. GFCI/AFCI should not be incorporated into any circuit other than receptacles in the bathroom, crawl space, garage next to opening, or bedroom receptacles. What is happening to common sense in the electrical field. Too many people are seeking input and a name for making a worthless change. To even think of putting any circuit related to fire protection or the like on either GFCI or AFCI is a no brainer.

If the 120 volt circuit isnt the power source what is? I have three wire smokes in my house, when one gos off they all go, If i lose power all will stop working. Putting any system on an arc fault breaker is asking for trouble.

Author’s Comment: This GFCI/AFCI limitation only applies to the circuit that supplies a nonpower-limited fire alarm system. Smoke detectors connected to a 15 or 20A, 120V circuit must be AFCI-protected if located in the bedroom of a dwelling unit [210.12(B)]; because according to NFPA 72, National Fire Alarm Code the circuit for the smoke detectors isn’t the power source of a nonpower-limited fire alarm circuit.

Does the requirement for smoke detectors connected to a 15 or 20A, 120V circuit requiring AFCI protection only apply to smoke detectors located in a bedroom, or does the 2008 Code require protection for smoke detectors in other areas as well?

So you are telling us that there is another 120 volt soures that is GFIC protected just for smoke detection. If ther is a fire alarm panel required for this residenial property, would these smoke detectors required to be connected to the fire alarm panel to cause alarm condictions to notify the Fire Dept. or Police Dept.

The problem here is the circuit the smoke detector is on not the power source for a fire alarm system. Most homes do not have fire alarm systems. This is where you are having the problems.

My Supervisor serves on the UL fire council. He also chaired the NFPA-72 committee on initiating devices for 10 years. He says this is a real problem that although the UL fire council and the NFPA-72 committees have brought this to the NFPA-70 committee's attention they have failed to adress it.

He also says this AFCI protection affects how the detector reads its algorithms in some way. This causes false alarms and other problems.

Jim Yancey-NCDOI

What is the application for non-power limited firealarm systems? Thanks, David

The electrical inspector on my house required a separate, non-afci, circuit for the smoke detectors. His reasoning was that he did not want the detector to trip in the event there was an arc fault in the bedroom. Apparently this is a cause of fire and he wanted the detector live regardless

The pratice of putting the smoke alarms on a dedicated 15A circuit is required by the AHJD in our area, and we also see it on some plans drawn they way by engineers.

Mike

Just a quick comment. We need to differenciate between a smoke detector and smoke alarm. Smoke detectors are part of a fire alarm system, a smoke alarms are a requirement of the building code, which in turn refers you to NFPA 72, under chapter 11. Where you will find that "smoke alarms powered by AFCI-protected circuits shall have a secondary power" (11.6.3(5) nfpa 72). So, when it comes both NPLFA and PLFA, neither systems shall be supply through a GFCI or AFCI. Thanks.

Apologize for the word "differentiate". Thanks