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 Sizing

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

												Master Bundles
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
1/2	16	30	13.6	0.706	17.9	0.042	1.07	100	30.5	7000	2135.0	2100	952.4	28.7	0.81
3/4	21	46	20.9	0.922	23.4	0.049	1.25	100	30.5	5000	1525.0	2300	1043.1	35.6	1.01
1	27	67	30.4	1.163	29.5	0.057	1.45	100	30.5	3000	915.0	2010	911.6	33.7	0.95
1 1/4	35	101	45.8	1.510	38.4	0.065	1.65	50	15.2	2000	610.0	2020	916.1	35.0	0.99
1 1/2	41	116	52.6	1.740	44.2	0.065	1.65	50	15.2	1500	457.5	1740	789.10	34.2	0.97
2	53	148	67.1	2.197	55.8	0.065	1.65	-	-	1200	366.0	176	805.4	46.7	1.32
2 1/2	63	216	98.0	2.875	73.0	0.072	1.83	-	-	610	186.1	1318	597.7	41.5	1.18
3	78	263	119.3	3.500	88.9	0.072	1.83	-	-	510	155.6	1341	608.2	48.9	1.38
3 1/2	91	349	158.3	4.000	101.6	0.083	2.11	-	-	370	112.9	1291	585.5	48.6	1.38
4	103	393	178.2	4.500	114.3	0.083	2.11	-	-	300	91.5	1179	534.7	48.3	1.37