Article 348 Flexible Metal Conduit: Type FMC
Flexible Metal Conduit (FMC). A raceway of circular cross section made of helically wound, formed, interlocked metal strip.
- In wet locations
- In hoistways, other than as permitted in 620.21(A)(1)
- In storage battery rooms
- In any hazardous (classified) location except as permitted by other articles in this Code
- Where exposed to materials having a deteriorating effect on the installed conductors, such as oil or gasoline
- Underground or embedded in poured concrete or aggregate
- Where subject to physical damage
- For enclosing the leads of motors as permitted in 430.245(B)
- In lengths not in excess of 1.8 m (6 ft) for any of the following uses:
- For manufactured wiring systems as permitted in 604.100(A)
- In hoistways as permitted in 620.21(A)(1)
- As part of a listed assembly to connect wired luminaire sections as permitted in 410.137(C)
Informational Note: See 300.1(C) for the metric designators and trade sizes. These are for identification purposes only and do not relate to actual dimensions.
|Types RFH-2, SF-2||Types TF, XHHW, TW||Types TFN, THHN, THWN||Types FEP, FEBP, PF, PGF|
|Size (AWG)||Fittings Inside Conduit||Fittings Outside Conduit||Fittings Inside Conduit||Fittings Outside Conduit||Fittings Inside Conduit||Fittings Outside Conduit||Fittings Inside Conduit||Fittings Outside Conduit|
|*In addition, one insulated, covered, or bare equipment grounding conductor of the same size shall be permitted.|
Cables shall be permitted to be installed where such use is not prohibited by the respective cable articles. The number of cables shall not exceed the allowable percentage fill specified in Table 1, Chapter 9.
Exception No. 1: Where FMC is fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable.
Exception No. 2: Where flexibility is necessary after installation, lengths from the last point where the raceway is securely fastened shall not exceed the following:
- 900 mm (3 ft) for metric designators 16 through 35 (trade sizes 1/2 through 11/4)
- 1200 mm (4 ft) for metric designators 41 through 53 (trade sizes 11/2 through 2)
- 1500 mm (5 ft) for metric designators 63 (trade size 21/2) and larger
Exception No. 4: Lengths not exceeding 1.8 m (6 ft) from the last point where the raceway is securely fastened for connections within an accessible ceiling to a luminaire(s) or other equipment. For the purposes of this exception, listed flexible metal conduit fittings shall be permitted as a means of securement and support.