There’s some confusion about what raceway is, so let’s define that first. Per NFPA 70, Art. 100 and NFPA 70E Ar.100, raceway is “An enclosed channel of metal or nonmetallic materials expressly designed for holding wires, cables, or bus bars with additional functions as permitted in this standard.” (In the NEC, “Code” is used in place of “standard.”)
Many people erroneously say “conduit” when they mean raceway or refer to some kind of tubing (typically EMT) as “conduit.” Conduit has particular properties of construction, assembly, and performance that differentiate it from tubing. This has important safety implications. For example, you can use conduit in a Class I, Div. 1 installation but you cannot use tubing there.
To better understand how conduit and tubing differ, go to Chapter 3 of the NEC and compare the articles covering conduit types (342 through 356) to those covering tubing types (358 through 362). You will also see some types of raceway that are neither conduit nor tubing.
Some safety concerns vary, depending on the type of raceway.
