Class I locations.
Municipal Code of Chicago § 14E-5-501
in effect14E-5-501 Class I locations.
The provisions of Article 501 of NFPA 70 are adopted by reference with the following modifications:
1. Revise subsections 501.10(A)(1) and (A)(2) to read:
"(1) General. In Class I, Division 1 locations, the wiring methods in (a) through (c) shall be permitted.
(a) Threaded rigid metal conduit or threaded steel intermediate metal conduit.
(b) Type MI cable terminated with fittings listed for the location. Type MI cable shall be installed and supported in a manner to avoid tensile stress at the termination fittings.
(c) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN and OFC shall be permitted to be installed in raceways in accordance with 501.10(A). These optical fiber cables shall be sealed in accordance with 501.15.
Exception: Type PVC conduit, Type RTRC conduit, and Type HDPE conduit shall be permitted where encased in a concrete envelope a minimum of 50 mm (2 in.) thick and provided with not less than 600 mm (24 in.) of cover measured from the top of the conduit to grade. The concrete encasement shall be permitted to be omitted where subject to the provisions of 514.8, Exception No. 2, or 515.8(A). Threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for the last 600 mm (24 in.) of the underground run to emergence or to the point of connection to the aboveground raceway. An equipment grounding conductor shall be included to provide for electrical continuity of the raceway system and for grounding of non-current-carrying metal parts.
(2) Flexible Connections. Where necessary to employ flexible connections, as at motor terminals, one of the following shall be permitted:
(1) Flexible fittings listed for the locations
(2) Flexible cord in accordance with the provisions of 501.140, terminated with cord connectors listed for the location."
2. Revise subsections 501.10(B)(1) and (B)(2) to read:
"(1) General. In Class I, Division 2 locations, the following wiring methods shall be permitted:
(1) All wiring methods permitted in 501.10(A).
(2) Enclosed gasketed busways and enclosed gasketed wireways.
(3) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725. The cable shall be terminated with listed fittings.
(4) Type MV and the cable shall be terminated with listed fittings.
(5) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall be permitted to be installed in any raceway in accordance with 501.10(B). Optical fiber cables shall be sealed in accordance with 501.15.
(2) Flexible Connections. Where provision must be made for limited flexibility, one or more of the following shall be permitted:
(1) Listed flexible metal fittings.
(2) Flexible metal conduit with listed fittings.
(3) Liquidtight flexible metal conduit with listed fittings.
(4) Flexible cord listed for extra-hard usage and terminated with listed fittings. A conductor for use as an equipment grounding conductor shall be included in the flexible cord.
(5) For elevator use, an identified elevator cable of Type EO, ETP, or ETT, shown under the "use" column in Table 400.4 for "hazardous (classified) locations" and terminated with listed fittings.
Informational Note: See 501.30(B) for grounding requirements where flexible conduit is used."
(Amend Coun. J. 10-7-20, p. 21791, Art. III, § 4)
Source: City of Chicago, Municipal Code of Chicago (American Legal Publishing, codelibrary.amlegal.com)URL: https://codelibrary.amlegal.com/codes/chicago/latest/chicago_il/0-0-0-2670284Fetched: 10/24/2026