I. General

355.1 Scope. This article covers the use, installation, and construction specification for reinforced thermosetting resin conduit (RTRC) and associated fittings.

FPN: Refer to Article 352 for Rigid Polyvinyl Chloride Conduit: Type PVC, and Article 353 for High Density Polyethylene Conduit: Type HDPE.

355.2 Definition.

Reinforced Thermosetting Resin Conduit

(RTRC). A

rigid nonmetallic conduit (RNC) of circular cross section, with integral or associated couplings, connectors, and fittings for the installation of electrical conductors and cables.

355.6 Listing Requirements. RTRC, factory elbows, and associated fittings shall be listed.

II. Installation

355.10 Uses Permitted. The use of RTRC shall be permitted in accordance with 355.10(A) through (H).

(A) Concealed. RTRC shall be permitted in walls, floors, and ceilings.

(B) Corrosive Influences. RTRC shall be permitted in locations subject to severe corrosive influences as covered in 300.6 and where subject to chemicals for which the mate- rials are specifically approved.

(C) Cinders. RTRC shall be permitted in cinder fill.

Wet Locations. RTRC shall be permitted in portions of dairies, laundries, canneries, or other wet locations, and in locations where walls are frequently washed, the entire conduit system, including boxes and fittings used therewith, shall be installed and equipped so as to prevent water from entering the conduit. All supports, bolts, straps, screws, and so forth, shall be of corrosion-resistant materials or be protected against corrosion by approved corrosion-resistant materials.

(E) Dry and Damp Locations. RTRC shall be permitted for use in dry and damp locations not prohibited by 355.12.
(F) Exposed. RTRC shall be permitted for exposed work where not subject to physical damage if identified for such use.

(G) Underground Installations. For underground installations, see 300.5 and

300.50.

(H) Support of Conduit Bodies. RTRC shall be permitted to support nonmetallic conduit bodies not larger than the largest trade size of an entering raceway. These conduit bodies shall not support luminaires or other equipment and shall not contain devices other than splicing devices as permitted by 110.14(B) and

314.16(C)(2).

355.12 Uses Not Permitted. RTRC shall not be used under the following conditions.

(A) Hazardous (Classified) Locations.

(1) In any hazardous (classified) location, except as permitted by other articles in this Code

(2) In Class I, Division 2 locations, except as permitted in 501.10(B)(3)

(B) Support of Luminaires. For the support of luminaires or other equipment not described in

355.10(H).

(C) Physical Damage. Where subject to physical damage unless identified for such use.

(D) Ambient Temperatures. Where subject to

ambient temperatures in excess of 50°C (122°F)
unless listed otherwise.
(E) Insulation Temperature Limitations. For conductors or cables operating at a emperature higher than the RTRC listed operating temperature rating.

Exception: Conductors or cables rated at a temperature higher than the RTRC listed temperature rating shall be permitted to be installed in RTRC, provided they are not operated at a temperature higher than the RTRC listed temperature rating.

(F) Theaters and Similar Locations. In theaters and similar locations, except as provided in

518.4 and 520.5.

355.20 Size.

(A) Minimum. RTRC smaller than metric designator 16 (trade size Vi) shall not be used.

(B) Maximum. RTRC larger