336-4(a)of the 1999 NEC states: "Type NM cable shall be permitted for both exposed and concealed work in normally dry locations." The local authorities, I am working with, presently reconize the 1999 NEC. I want to install Type NM (Romex)cable in the below grade crawl spaces of 6 buildings. These below grade crawl spaces have grade level open ventilation vent fans, access hatches, and louvers to the outdoors. The environemnt in the crawl spaces is humid and damp, and some times wet (due to infiltration of rain water). Would the installation of the Type NM cable in the below grade crawl spaces be in complience with the NEC's requirements.
Type NM Cable Installation
- Thread starter jpschultz
- Start date
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kevinware
Senior Member
- Location
- Louisville, KY
Re: Type NM Cable Installation
Check the definitions in article 100 for Damp location and Dry location and Wet location. You could always look into using UF cable. Look at 340.10 and 340.12....
Sorry Jpschultz, the code references given are from 2005 NEC. Wait and see what others say that have access to the 1999 NEC.
[ August 03, 2005, 10:13 AM: Message edited by: kevinware ]
Check the definitions in article 100 for Damp location and Dry location and Wet location. You could always look into using UF cable. Look at 340.10 and 340.12....
Sorry Jpschultz, the code references given are from 2005 NEC. Wait and see what others say that have access to the 1999 NEC.
[ August 03, 2005, 10:13 AM: Message edited by: kevinware ]
charlie
Senior Member
- Location
- Indianapolis
Re: Type NM Cable Installation
From the 1999 NEC,
336-4(a) Type NM. Type NM cable shall be permitted for both exposed and concealed work in normally dry locations. It shall be permissible to install or fish Type NM cable in air voids in masonry block or tile walls where such walls are not exposed or subject to excessive moisture or dampness.
From the 1999 NEC,
336-4(a) Type NM. Type NM cable shall be permitted for both exposed and concealed work in normally dry locations. It shall be permissible to install or fish Type NM cable in air voids in masonry block or tile walls where such walls are not exposed or subject to excessive moisture or dampness.
wbalsam1
Senior Member
- Location
- Upper Jay, NY
Re: Type NM Cable Installation
Hi jpschultz:
I believe the emphasis is pointed towards the paper-covered equipment grounding conductor within the NM cable. If it gets wet and corrodes, the ground-fault return-current path could be jeopardized. This would be an unsafe condition. The crawl space is more than likely a damp location, and so are the voids in masonry units at outside walls. As such, NM would be prohibited from being installed in these areas.
Hi jpschultz:
I believe the emphasis is pointed towards the paper-covered equipment grounding conductor within the NM cable. If it gets wet and corrodes, the ground-fault return-current path could be jeopardized. This would be an unsafe condition. The crawl space is more than likely a damp location, and so are the voids in masonry units at outside walls. As such, NM would be prohibited from being installed in these areas.
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
Re: Type NM Cable Installation
A suitable product from damp areas in place of UF cable in NMC cable.
334.10
(B) Type NMC. Type NMC cable shall be permitted as follows:
(1) For both exposed and concealed work in dry, moist, damp, or corrosive locations, except as prohibited in 334.10(3)
(2) In outside and inside walls of masonry block or tile
(3) In a shallow chase in masonry, concrete, or adobe protected against nails or screws by a steel plate at least 1.59 mm ( in.) thick and covered with plaster, adobe, or similar finish
Now the big question: who makes NMC cable?
A suitable product from damp areas in place of UF cable in NMC cable.
334.10
(B) Type NMC. Type NMC cable shall be permitted as follows:
(1) For both exposed and concealed work in dry, moist, damp, or corrosive locations, except as prohibited in 334.10(3)
(2) In outside and inside walls of masonry block or tile
(3) In a shallow chase in masonry, concrete, or adobe protected against nails or screws by a steel plate at least 1.59 mm ( in.) thick and covered with plaster, adobe, or similar finish
Now the big question: who makes NMC cable?
charlie
Senior Member
- Location
- Indianapolis
Re: Type NM Cable Installation
Tom, I believe the answer to that one is no one makes NMC. However, UF works fine in its place.
Tom, I believe the answer to that one is no one makes NMC. However, UF works fine in its place.
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