Emergency Lighting Rehash

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shroominator

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Has anyone come up with a firm answer to the old question of one or two lamps required at exterior egress doors?

See what I'm talking about here:

http://www.mikeholt.com/code_forum/showthread.php?t=67923&highlight=emergency+lighting+required

I have always designed with one head on the outside in many parts of the country and have never been called on it. Still haven't actually (have a contractor shaking the bushes).

Also, NFPA 700.16 does not specifically state "exterior egress illumination", so wouldn't the two lamp situation apply to all interior egress lighting as well?

Thanks for any help.

Craig
 
I'm a little confused on the "two sources" of power requirement. A good deal of the egress lighting I have designed in is only lit during a power outage, i.e. fed through through the wall from an exit sign battery. The area would be lit by other sources under normal operating conditions. So, these egress fixtures only have one source of power, yet the area is still always lit as required.
 
Its not an nec issue.
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Actually it is, read 700.16.

"Emergency lighting systems shall be designed and installed so that the failure of any individual lighting element, such as the burning out of a light bulb, cannot leave in total darkness any space that requires emergency illumination."

The exterior side of a required exit discharge door requires emergency illumination so it must comply with 700.16.

Now here is the big debate, what is "Total darkness". Is there such a thing as "total darkness" outside?

Chris
 
raider1 said:
Actually it is, read 700.16.

"Emergency lighting systems shall be designed and installed so that the failure of any individual lighting element, such as the burning out of a light bulb, cannot leave in total darkness any space that requires emergency illumination."

The exterior side of a required exit discharge door requires emergency illumination so it must comply with 700.16.

Now here is the big debate, what is "Total darkness". Is there such a thing as "total darkness" outside?

Chris
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Its hard to create that even inside.I love to sleep in total darkness.Is an outside light ever an emergency ? If so to who and why.
 
JMO,

If a light is on ( in a required area ) it is not dark, if the only light around is

off, it's dark, if other lights in the general area shed some light to this area

it would not be in total darkness.
 
benaround said:
JMO,

If a light is on ( in a required area ) it is not dark, if the only light around is

off, it's dark, if other lights in the general area shed some light to this area

it would not be in total darkness.
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Isnt there always some light from the sun or moon ?
 
Is an outside light ever an emergency ? If so to who and why.
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Yes, the exit discharge of a building has to have emergency illumination. This requirement comes from the building code.

The IBC reads:
1006.1 Illumination required. The means of egress, including
the exit discharge, shall be illuminated at all times the building
space served by the means of egress is occupied.
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And here is the definition of "Exit discharge"

EXIT DISCHARGE. That portion of a means of egress system
between the termination of an exit and a public way.
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So you are required to have emergency lighting to the public way.

Chris
 
I believe there is a 1 ft/candle power requirement for egress path lighting - inside or out... Not sure what code though.... And do not think that the moon would count legaly... Cloudy moon-less night power-outage...
 
There is also a 1 1/2 hour required stand by time for illumination.

e57 I believe you are correct also on the 1 f/c requirement, but I have not found the code reference either. I remember reading this but not sure if I read it in the Life Safety Code or NEC. I will continue my search.
 
The 1 foot-candle requirment comes from the building code as well.

Here is what the IBC requires

1006.2 Illumination level. The means of egress illumination
level shall not be less than 1 foot-candle (11 lux) at the walking
surface level.
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Chris
 
shroominator said:
I suppose I'll just cave in and use the double head remote. I'll have to bump up the interior unit, but....

Thanks for all the comments, it's been good to have so much input.
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I read thru this post rather quickly, so forgive me if I am off on a tangent. Article 700 requires two light sources, not two lamps on the emergency fixture. If you have a normal fixture, say a recessed can or a wall pack, your separate emergency fixture only needs one lamp.

If you have a normally powered recessed fixture, for example, with a battery for back up and it is the only fixture lighting the area, then it must have two lamps.

Jim T
 
In my neck of the woods, the interpretation is TWO heads outside each exit door and an area light. Based on the codes, I gotta agree. I spec the nearest inside emergency unit to be oversized to cover the external heads. You really want to avoid having the batteries outside, low AND high temps really do a number on them. But, with that said, you can't always do that, such as exterior corridors in apartment buildings. Be sure the heads are NEMA 3R. RC
 
I spec the nearest inside emergency unit to be oversized to cover the external heads.
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You might want to look at 700.12(F) there is a part of that section that requires that the unit equipment be fed from the same circuit that feeds the normal lighting in the area.

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

So if the outside lights are on a separate circuit from the interior lighting then the unit equipment must be fed from the outside lighting circuit.

There is an exception for areas that are supplied by a minimum of 3 normal lighting circuits, you can use a separate branch circuit for the unit equipment if it originates from the same panelboard as that if the normal lighting circuits and is provided with a lock-on feature.

Chris
 
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