Electrical Metallic Tubing
Electrical metallic tubing (EMT), also commonly called thin-wall, is a listed steel raceway of circular cross section, which is unthreaded, and nominally 10′ long. 20′ lengths are also available. Covered by Article 358 of the NEC, EMT is available in trade sizes 1/2 through 4. The outside is galvanized for corrosion protection and the inside has an approved corrosion-resistant organic coating. EMT is installed by use of set-screw or compression-type couplings and connectors. It is permitted to have an integral coupling comprised of an expanded, “belled” shape tube on one end with set screws. EMT with integral couplings is available in trade sizes 1-1/4 through 4.
Electrical Code Compliance
EMT is covered by Article 358 of the NEC®.
EMT is available in trade sizes 1/2 through 4, and 10′ and 20′ lengths. Some manufacturers also produce EMT in a range of colors for easy system identification.
EMT Weights and Dimensions
|Trade Size Designator||Nominal Wt. per 100 Ft. (30.5m.)||Nominal Outside Diameter||Nominal Wall Thickness||Quantity in Primary Bundle||Quantity||Approx Wt.||Volume|
|US||Metric||lb.||kg||in.||mm||in.||mm||ft.||m||ft.||mm||lb.||kg||cu ft.||cu m|
UL and NEC Requirements for Corrosion Protection for Steel Conduit and EMT
Steel Conduit and EMT: Proven to Meet the NEC Requirements for Equipment Grounding
Steel Conduit Holds Steady