Branch Circuit For Exit Signs

[steve66]

Does anyone think that 700.12(E)- Unit Equipment applies to exit signs? Part of it says:

"The branch circuit feeding the unit equipemnt shall be the same branch circuit as that serving the normal lighting in the area and connected ahead of any local switches."


In particular, an inspector wants an exit sign (w/ an integral battery) connected to the same branch circuit as the room lighting.

My feeling is that this is to only assure that when the regular lights go out, the emergency lights come on. But an exit sign is always lit (under normal conditions and during power failures).

Steve

 

[infinity]

Re: Branch Circuit For Exit Signs

I would look at 700.12(F)(4). This mentions Unit Equipment. If an exit sign is unit equipment than your inspector is correct.

[ May 16, 2005, 05:00 PM: Message edited by: infinity ]

 

[ryan_618]

Re: Branch Circuit For Exit Signs

I agree with infinity, the inspector is correct.

 

[don_resqcapt19]

Re: Branch Circuit For Exit Signs

In this case, I think that the exit light itself is the area lighting and there is no requirement that the exit light be connected to the circuit that provides the room lighting. Look at it this way. If the room and exit lights are on independent circuits and the room circuit fails, what happens to the exit light? It stays at its full normal level of illumination. If it was on the room circuit, it would switch to battery providing a lower level of illumination. If the exit light circuit fails and the room circuit does not, then the exit light switches to battery. If the utility fails, the exit light switches to battery. I see no advantage or code reason to put the exit light on the room lighting circuit.
Don

 

[ryan_618]

Re: Branch Circuit For Exit Signs

The reason, in my opinion, is so the owner can't turn off the circuit controlling the exit light without also turning off the lighting in the area. For example, if the exit was on its own circuit, you could turn the circuit off, drain the battery and be left without an exit sign...all without knowing that you did anything.

 

[don_resqcapt19]

Re: Branch Circuit For Exit Signs

Ryan,
I just don't see how 700.12(E) applies....the exit light does not provide "the normal lighting in the area". I do you see your point about shutting off the power to the exit lights, but if they don't see that the exits are off, they wouldn't replace the lamps in the exits when they burn out.
Don

 

[infinity]

Re: Branch Circuit For Exit Signs

It has been my experience that exit signs in a tenant space of an office building can be out for months or longer before anyone notices. For the most part the people working there don't know or don't care if they're illuminated. I like Ryan's thought about someone noticing if the lighting circuit in the area being out.

 

[ryan_618]

Re: Branch Circuit For Exit Signs

I think 700.12(E) does apply. When you look at 700.12, it states that it applies to both emergancy lighting and emergancy power. When I read chapter 27 of the IBC, it states that exit signs must be supplied by emergancy power. I think for these reasons, it applies. An exit sign contains everything described in 700.12(E)(1)-(4), so I believe it to be unit equipment. Onbce we establish that, the rest of 700.12(E), include the branch circuit source, must be followed.

Regarding your next point with the owner not knowing the lamps had burned out, hopefully they would notcie when they shut the general purpose lights off (with the snap switch) when leaving the building at night.

 

[infinity]

Re: Branch Circuit For Exit Signs

Regarding your next point with the owner not knowing the lamps had burned out, hopefully they would notice when they shut the general purpose lights off (with the snap switch) when leaving the building at night

I was thinking of a commercial office building where the owner almost never walks onto a tenant floor and the tenant will never notice exit signs being out. That why I liked your idea about using the area lighting circuit. Someone couldn't turn tht circuit off without it being noticed. But is it a code requirement for exit signs? That would depend on your interpretation of what unit equipment is and if an exit sign fits that definition.

 

[roger]

Re: Branch Circuit For Exit Signs

If we are going to worry about EM lighting being reliable, someone will have to insure the required testing of these lights or the whole show is not in compliance with NFPA codes, specifically 101. I can't say whether or not other codes such as the UBC or IBC have the same requirements.

Roger

 

[don_resqcapt19]

Re: Branch Circuit For Exit Signs

Ryan,
I don't see exit signs as supplying "emergency illumination" which is the subject of 700.12(E). Even if the exit sign is covered by 700.12(E), it is its own area and provides its own illumination and can therefore be on any circuit. I can see no reasonable interpretation of the code that would require an exit sign with battery backup to be connected to the circuit that provides the general room illumination.

Regarding your next point with the owner not knowing the lamps had burned out, hopefully they would notice when they shut the general purpose lights off (with the snap switch) when leaving the building at night.

The would notice that but not this????

For example, if the exit was on its own circuit, you could turn the circuit off, drain the battery and be left without an exit sign...all without knowing that you did anything.

Don

[ May 16, 2005, 10:42 PM: Message edited by: don_resqcapt19 ]

 

[mc5w]

Re: Branch Circuit For Exit Signs

I know someone who has a for hire gymnasium with 2 hot leads and a neutral going to each exit sign. Both hot leads are on the same circuit and the unswitched hot lead runs the charger for the battery. The switched hot lead runs the 130 volt incandescent bulbs. Since the only people who have keys are people who are trained to turn the exit lights on and off there is no problem.

Since the facility spends 2/3 to 3/4 of the time unoccupied this save quite a bit on incandescent bulb life. At 16 cents per kilowatthour it also saves quite a bit of money.

If somebody forgets to turn on the exit lights the exit sign would still be illuminated by the room lights or by sunlight coming in the windows. There are 5 circuits for normal lighting and 4 of these are used when running baseketball games or dance lessons. If the utility power goes out the backup bulbs go on.

All of this was done before the days of LED exit signs. LEDs use so little power that switching off the normal power does not help and in fact you cannot do that because both the battery charger and the LEDs run off of the same power supply.

 

[ryan_618]

Re: Branch Circuit For Exit Signs

Ryan,
I don't see exit signs as supplying "emergency illumination" which is the subject of 700.12(E).

Don, I don't see where you are getting this from.

 

[don_resqcapt19]

Re: Branch Circuit For Exit Signs

Ryan,
I just don't see an exit sign as "illumination" especially when you look at the level of "brightness" given off by the radioactive exit signs. The exit sign is not intended to light the area, but only to make the word "exit" visible when the power is off.
Don

 

[steve66]

Re: Branch Circuit For Exit Signs

I almost always specify LED emergency lights, so lamps burning out isn't usually an issue. Power consumption isn't an issue either.

I can understand Ryan's post about someone turning off the branch circuit for the exit lights, and the batteries dying. I guess I will have to give the inspector the benefit of the doubt and comply with this from now on.

However, I am having a hard time understanding how this fits in with hospitals, where the exit lights are placed on the life safety branch. I guess it is just less likely a hospital would shut off a life safety branch circuit.

Steve

 

[roger]

Re: Branch Circuit For Exit Signs

Steve, see NFPA 101 7.8, 7.9, and 7.10 (NFPA 70 517.32(A)&(B)'s reference to 5.8, 5.9, & 5.10 in the 02 edition was a typo).

Take note of the wording in 7.8.2.2 for where some exit lights can be used for EM illumination.

Roger

 

[volt101]

Re: Branch Circuit For Exit Signs

700.16 Emergency Illumination
Emergency illumination shall include all required means of egress lighting, illuminated exit signs , and all other lights specified as necessary to provide required illumination.

I would say that the unit equipment - exit sign needs to be connected ahead of any switches that supply the normal illumination of the room, unless the three circuit exception is used.

Jim

 

[ryan_618]

Re: Branch Circuit For Exit Signs

Don, the unit equipment (whether we are talking about exit signs or emergancy lights) doesn't provide the normal lighting. Think of a bug-eye pack...that only comes on when the lights are off...it doesn't supply normal illumination, it just supplies emergancy illumination.

I don't think 700.12(E) has anything to do with the area lighting. All it is saying is that if you have unit equipment that meets the specifications described in (1)-(4), you must wire it to the same circuit as the normal lighting.

Ryan

 

[don_resqcapt19]

Re: Branch Circuit For Exit Signs

Ryan,
We will have to agree to disagree on this one. I do not see the exit light as covered by 700.12(E). The intent of that section is to make sure that the emergency lights come on if the circuit that provides the power to the normal lighting in the area is not available. The exit signs do not provide the normal lighting to the area and are not, in my opinion, covered by this section.
Don

 

[benaround]

Re: Branch Circuit For Exit Signs

If you are in a smoke filled area of a burning building, the only light that illuminates red is the one that might save your life,it better be ON

frank