1 & 2 HR RATING

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mstrlucky74

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Little confused as to the one hour rating requirement. Use to 2 hour. Note #1 sayd one hour rating for ALL emergency feeders. Color code calls for code required EM and optional EM feeders. Spec says one hour rating only required in non sprinkler protected areas. 99% of feeders are in sprinkler protected areas so I guess one hour is not required??? How is one hour ratings of feeders achieved. RGS? I'm fine with the 2 hour rating. Thanks.
 

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Isn't the entire building sprinklered? If so sounds like you do not need any one hour rated wiring methods.
 
infinity said:
Isn't the entire building sprinklered? If so sounds like you do not need any one hour rated wiring methods.
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Yes almost entire building....just concerned about one hour feeders rising up in stacked electrical closets but that should be sprinklered too.
 
mstrlucky74 said:
Yes almost entire building....just concerned about one hour feeders rising up in stacked electrical closets but that should be sprinklered too.
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It says no one hour rated wiring methods are required if the building is sprinklered which it is. Sounds like boiler plate specs.
 
infinity said:
It says no one hour rated wiring methods are required if the building is sprinklered which it is. Sounds like boiler plate specs.
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No it says in sprinkler protected AREAS. So maybe not all areas, like electrical closets, are protected. I can check fire protection drawings. So what pipe and wire combo gives a 1 hour fire rating? Thanks.
 
mstrlucky74 said:
No it says in sprinkler protected AREAS. So maybe not all areas, like electrical closets, are protected. I can check fire protection drawings. So what pipe and wire combo gives a 1 hour fire rating? Thanks.
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What type of building is it? There are actually areas without sprinklers?
 
mstrlucky74 said:
hotel. What would conduit/wire combo would give one hour rating.
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EM feeders need extra protection per 700.10(D). A method that provides one hour protection is not acceptable.

(D) Fire Protection. Emergency systems shall meet the additional
requirements in (D)(1) through (D)(3) in the following
occupancies:
(1) Assembly occupancies for not less than 1000 persons
(2) Buildings above 23 m (75 ft) in height
(3) Health care occupancies where persons are not capable
of self preservation
(4) Educational occupancies with more than 300 occupants
(1) Feeder-Circuit Wiring. Feeder-circuit wiring shall meet
one of the following conditions:
(1) The cable or raceway is installed in spaces or areas that
are fully protected by an approved automatic fire suppression
system.
(2) The cable or raceway is protected by a listed electrical
circuit protective system with a minimum 2-hour fire
rating.
Informational Note No. 1: Electrical circuit protective systems
could include but not be limited to thermal barriers or a protective
shaft and are tested to UL 1724, Fire Tests for Electrical Circuit
Protection Systems.
Informational Note No. 2: The listing organization provides
information for electrical circuit protective systems on proper
installation requirements to maintain the fire rating.
(3) The cable or raceway is a listed fire-resistive cable system.
Informational Note No. 1: Fire-resistive cables are tested to
ANSI/UL 2196, Tests for Fire Resistive Cables.
Informational Note No. 2: The listing organization provides
information for fire-resistive cable systems on proper installation
requirements to maintain the fire rating.
(4) The cable or raceway is protected by a listed fire-rated
assembly that has a minimum fire rating of 2 hours and
contains only emergency circuits.
(5) The cable or raceway is encased in a minimum of 50 mm
(2 in.) of concrete.
 
mstrlucky74 said:
Ok. Again is there such a things as a conduit/wire combo that is 1 hour rated?
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No. None. Nada. You either move up to VitaLink with 2 hours, or you build a soffit around the cable. If it's going up a stack of electrical closets and those are 1-hour rated then you're good. There are also a bunch of wraps and whatnot that you can use, but probably way more cost in labor than just using 2-hour, unless it really is only a few feet here and there. Hunt around the UL site for the rated assemblies.
 
gadfly56 said:
Does not prevent the cable inside from being incinerated.
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Which means a decision needs to be made as to whether the wiring needs protected from heat or if building/structure needs protected from heat that may develop in the wiring. How critical the circuit is can be a factor here.
 
kwired said:
Which means a decision needs to be made as to whether the wiring needs protected from heat or if building/structure needs protected from heat that may develop in the wiring. How critical the circuit is can be a factor here.
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The only decision that needs to be made is that is an emergency circuit or not. If it is indeed and emergency circuit, it needs to be protected in accordance with 700.10(D). We use Chapter 27 of the IBC to determine what is an emergency load, since that is the building code adopted here.
 
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