I. General
354.1 Scope. This article covers the use, installation, and construction specifications for nonmetallic underground conduit with conductors (NUCC).
354.2 Definition.
Nonmetallic Underground Conduit with Conductors
(NUCC). A factory assembly of conductors or cables inside a nonmetallic, smooth wall conduit with a circular cross section.
354.6 Listing Requirements. NUCC and associated fit- tings shall be listed.
II. Installation
354.10 Uses Permitted. The use of NUCC and fittings shall be permitted in the following:
(1) For direct burial underground installation (For mini-
(3) In any hazardous (classified) location, except as permit
ted by other articles of this Code
354.20 Size.
(A) Minimum. NUCC smaller than metric designator 16 (trade size Vi) shall not be used.
(B) Maximum. NUCC larger than metric designator 103 (trade size 4) shall not be used.
FPN: See 300.1(C) for the metric designators and trade sizes. These are for identification purposes only and do not relate to actual dimensions.
354.22 Number of Conductors. The number of conduc- tors or cables shall not exceed that permitted by the percentage fill in Table 1, Chapter 9.
354.24 Bends — How Made. Bends shall be manually made so that the conduit will not be damaged and the internal diameter of the conduit will not be effectively reduced. The radius of the curve of the centerline of such bends shall not be less than shown in Table
354.24.
Table 354.24 Minimum Bending Radius for Nonmetallic
Underground Conduit with Conductors (NUCC)
Minimum Bending
Conduit Size Radius
mm in.
mum cover requirements, see Table 300.5 and Table
300.50 under Rigid Nonmetallic Conduit.)
(2) Encased or embedded in concrete
(3) In cinder fill
(4) In underground locations subject to severe corrosive influences as covered in 300.6 and where subject to chemicals for which the assembly is specifically approved
(5) Aboveground, except as prohibited in 354.12,
16 '/2
3/4
27 1
35 VA
41 V/z
53 2
63 2'/2
78 3
103 4
250 10
300 12
350 14
450 18
500 20
650 • 26
900 36
1200 48
1500 60
where encased in not less than 50 mm (2 in.) of concrete.
354.12 Uses Not Permitted. NUCC shall not be used in the following:
(1) In exposed locations
(2) Inside buildings
Exception: The conductor or the cable portion of the assembly, where suitable, shall be permitted to extend within the building for termination purposes in accordance with 300.3.
354.26 Bends — Number in One Run. There shall not
be more than the equivalent of four quarter bends (360
degrees total) between termination points.
354.28 Trimming. For termination, the conduit shall be trimmed away from the conductors or cables using an approved method that will not damage the conductor or cable insulation or jacket. All conduit ends shall be trimmed inside and out to remove rough edges.
354.46 Bushings. Where the NUCC enters a box, fitting, or other enclosure, a bushing or adapter shall be provided to protect the conductor or cable from abrasion unless the design of the box, fitting, or enclosure provides equivalent protection.
FPN: See 300.4(G) for the protection of conductors