I. General
353.1 |
Scope |
353.2 |
Definition |
A conduit that is circular in cross section with its associated couplings, connectors, etc. that is nonmetallic and used for the installation of electrical conductors.
353.6 |
Listing Requirements. |
II. Installation
353.10 |
Uses Permitted |
In can be used in cinder fill; in continuous lengths from a reel or discrete lengths; in areas that are corrosive as noted in 300.6 and where the conduit is listed for use where subject to certain chemicals; and for direct burial in earth or concrete (refer to 300.5 and 300.50 for underground installations).
353.12 |
Uses Not Permitted |
It cannot be used where exposed; in hazardous (classified) locations unless permitted in 504.20; within a building; in ambient temperatures higher than 50°C (122°F) unless listed for higher; for conductors or cables operating at a higher temperature than the conduit listed operating temperature. There is an exception.
353.20 |
Size |
You cannot use a smaller size than metric designator 16 (trade size ½) or larger than metric designator 103 (trade size 4).
353.22 |
Number of Conductors |
Cannot exceed the percentage fill of Table 1, Chapter 9. Cables can be used if not prohibited by the cable articles. Cable cannot exceed the fill requirements of Table 1, Chapter 9.
353.24 |
BendsHow Made |
They must be manually made and must not be damaged. Refer to Table 354.24.
353.26 |
BendsNumber in One Run |
The maximum that is permitted is not more than 360° in bends between termination points.
353.28 |
Trimming |
Remove rough edges.
353.46 |
Bushings |
A bushing must be used at the point where the conduit goes into a box or fitting unless protection is provided in the box or fitting.
353.48 |
Joints |
Use approved methods.
353.56 |
Splices and Taps |
They are permitted only in accordance with Section 300.15.
353.60 |
Grounding |
A separate equipment grounding conductor must be installed where equipment ground is required. There are two exceptions.
III. Construction Specifications
353.100 |
Construction |
This conduit must be composed of nonmetallic material and must be resistant to moisture and chemical atmospheres. It must be resistant to moisture and corrosive agents. It must be strong enough to withstand abuse during installation. If used for direct burial without being encased in concrete, it must be able to withstand the continued loading after installation.
353.120 |
Marking |
It must be marked at least every 3 m (10 ft.) as noted in 110.21. The marking must include the type of material.
Article 90 Introduction
General
Wiring and Protection
Wiring Methods and Materials
Equipment for General Use
Special Occupancies
Special Equipment
Special Conditions
Tables
Annex C. Conduit and Tubing Fill Tables for Conductors and Fixture Wires of the Same Size
Annex D. Examples
Annex E. Types of Construction