OSP Fiber

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Klaw

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I have A question regarding the use of out side plant Fiber being used inside a building. I am well aware that the Fiber must be terminated within 50 feet of the point of entry and I have Expressed this to the customer. I told them they cannot run OSP Fiber inside a building from closet to closet. I told them it is a violation of the NEC code but they want proof. Does anyone know Where I can find that specific article?
 
Here is the article

770.48 Unlisted Cables and Raceways Entering Buildings.
(A) Conductive and Nonconductive Cables. Unlisted
conductive and nonconductive outside plant optical fiber
cables shall be permitted to be installed in building spaces,
other than risers, ducts used for environmental air, plenums
used for environmental air, and other spaces used for environmental
air, where the length of the cable within the
building, measured from its point of entrance, does not
exceed 15 m (50 ft) and the cable enters the building from
the outside and is terminated in an enclosure.

(B) Nonconductive Cables in Raceway. Unlisted nonconductive
outside plant optical fiber cables shall be permitted
to enter the building from the outside and shall be permitted
to be installed in any of the following raceways:
(1) Intermediate metal conduit (IMC)
(2) Rigid metal conduit (RMC)
(3) Rigid polyvinyl chloride conduit (PVC)
(4) Electrical metallic tubing (EMT)
Click to expand...
 
I read your second thread and closed it because we don't need another thread on this. You can explain it here if you want.

The customer wants to use cable that they have but it seems clear that the cable can only be used from the outside and not more than 50' inside the building. I posted the articles above. Present those articles to them
 
Dennis Alwon said:
Well, it cannot be installed without a raceway if you mean the OSP but there are cables listed for interior.
Click to expand...
You can't install OSP fiber between points within a building, even if it is in conduit. 770.48 only applies to fiber that enters from the outside and is extended to a remote location within the building.
 
don_resqcapt19 said:
You can't install OSP fiber between points within a building, even if it is in conduit. 770.48 only applies to fiber that enters from the outside and is extended to a remote location within the building.
Click to expand...

Perhaps my wording was not clear. I was saying the osp had to be in a raceway from the exterior to the point within 50', but maybe that is not true. I was saying there are listed cables to go between points inside the building
 
The section refers to unlisted OSP cable. Does this mean that there is also listed cable which meets flame transfer and other test and can therefore be used inside too?
In the case of URD, for example, the same cable may also be listed as a Chapter 3 wiring type.
OSP fiber needs to withstand outdoor stresses, but may also qualify for indoor use.
Or it might be less expensively constructed in other ways since for outdoor use it does not fall under NEC listing requirements?

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Don, where can I find that. You are saying the same thing that I am trying to prove to the customer!
 
Dennis Alwon said:
Perhaps my wording was not clear. I was saying the osp had to be in a raceway from the exterior to the point within 50', but maybe that is not true. I was saying there are listed cables to go between points inside the building
Click to expand...
The code section is very poorly written. I have no idea what (B) is trying to tell us, since (A) covers both conductive and non-conductive cables.

You are correct that are are fiber cables that are listed for use inside buildings.
 
don_resqcapt19 said:
The code section is very poorly written. I have no idea what (B) is trying to tell us, since (A) covers both conductive and non-conductive cables.

You are correct that are are fiber cables that are listed for use inside buildings.
Click to expand...
I think that the difference is that A limits the inside run to 50 feet while B allows an unlimited distance from entry for non-conductive in raceway.

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GoldDigger said:
I think that the difference is that A limits the inside run to 50 feet while B allows an unlimited distance from entry for non-conductive in raceway.

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Click to expand...
I can see that being read that way.

Either way, the OSP cannot be used between two points within a building.
 
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