NEC Chapter 9 Table 4

Article 358 - Electrical Metallic Tubing (EMT)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
21	¾	20.9	0.824	343	0.533	206	0.32	182	0.283	106	0.165	137	0.213
27	1	26.6	1.049	556	0.864	333	0.519	295	0.458	172	0.268	222	0.346
35	1 ¼	35.1	1.38	968	1.496	581	0.897	513	0.793	300	0.464	387	0.598
41	1 ½	40.9	1.61	1314	2.036	788	1.221	696	1.079	407	0.631	526	0.814
53	2	52.5	2.067	2165	3.356	1299	2.013	1147	1.778	671	1.04	866	1.342
63	2 ½	69.4	2.731	3783	5.858	2270	3.515	2005	3.105	1173	1.816	1513	2.343
78	3	85.2	3.356	5701	8.846	3421	5.307	3022	4.688	1767	2.742	2280	3.538
91	3 ½	97.4	3.834	7451	11.545	4471	6.927	3949	6.119	2310	3.579	2980	4.618
103	4	110.1	4.334	9521	14.753	5712	8.852	5046	7.819	2951	4.573	3808	5.901
Article 362 - Electrical Nonmetallic Tubing (ENT)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
21	¾	20.4	0.804	328	0.508	197	0.305	174	0.269	102	0.157	131	0.203
27	1	26.1	1.029	537	0.832	322	0.499	284	0.441	166	0.258	215	0.333
35	1 ¼	34.5	1.36	937	1.453	562	0.872	497	0.770	291	0.450	375	0.581
41	1 ½	40.4	1.59	1281	1.986	769	1.191	679	1.052	397	0.616	512	0.794
53	2	52	2.047	2123	3.291	1274	1.975	1125	1.744	658	1.020	849	1.316
63	2 ½	—	—	—	—	—	—	—	—	—	—	—	—
78	3	—	—	—	—	—	—	—	—	—	—	—	—
91	3 ½	—	—	—	—	—	—	—	—	—	—	—	—
Article 348 - Flexible Metal Conduit (FMC)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
16	½	16.1	0.635	204	0.317	122	0.19	108	0.168	63	0.098	81	0.127
21	¾	20.9	0.824	343	0.533	206	0.32	182	0.283	106	0.165	137	0.213
27	1	25.9	1.02	527	0.817	316	0.49	279	0.433	163	0.253	211	0.327
35	1 ¼	32.4	1.275	824	1.277	495	0.766	437	0.677	256	0.396	330	0.511
41	1 ½	39.1	1.538	1201	1.858	720	1.115	636	0.985	372	0.576	480	0.743
53	2	51.8	2.04	2107	3.269	1264	1.961	1117	1.732	653	1.013	843	1.307
63	2 ½	63.5	2.5	3167	4.909	1900	2.945	1678	2.602	982	1.522	1267	1.963
78	3	76.2	3	4560	7.069	2736	4.241	2417	3.746	1414	2.191	1824	2.827
91	3 ½	88.9	3.5	6207	9.621	3724	5.773	3290	5.099	1924	2.983	2483	3.848
103	4	101.6	4	8107	12.566	4864	7.54	4297	6.66	2513	3.896	3243	5.027
Article 324 - Intermediate Metal Conduit (IMC)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
16	½	16.8	0.66	222	0.342	133	0.205	117	0.181	69	0.106	89	0.137
21	¾	21.9	0.864	377	0.586	226	0.352	200	0.311	117	0.182	151	0.235
27	1	28.1	1.105	620	0.959	372	0.575	329	0.508	192	0.297	248	0.384
35	1 ¼	36.8	1.448	1064	1.647	638	0.988	564	0.873	330	0.51	425	0.659
41	1 ½	42.7	1.683	1432	2.225	859	1.335	759	1.179	444	0.69	573	0.89
53	2	54.6	2.15	2341	3.63	1405	2.178	1241	1.924	726	1.125	937	1.452
63	2 ½	64.9	2.557	3308	5.135	1985	3.081	1753	2.722	1026	1.592	1323	2.054
78	3	80.7	3.176	5115	7.922	3069	4.753	2711	4.199	1586	2.456	2046	3.169
91	3 ½	93.2	3.671	6822	10.584	4093	6.351	3616	5.61	2115	3.281	2729	4.234
103	4	105.4	4.166	8725	13.631	5235	8.179	4624	7.224	2705	4.226	3490	5.452
Article 356 - Liquidtight Flexible Nonmetalic Conduit (LFNC-B)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
16	½	16.1	0.632	204	0.314	122	0.188	108	0.166	63	0.097	81	0.125
21	¾	21.1	0.83	350	0.541	210	0.325	185	0.287	108	0.168	140	0.216
27	1	26.8	1.054	564	0.873	338	0.524	299	0.462	175	0.27	226	0.349
35	1 ¼	35.4	1.395	984	1.528	591	0.917	522	0.81	305	0.474	394	0.611
41	1 ½	40.3	1.588	1276	1.981	765	1.188	676	1.05	395	0.614	510	0.792
53	2	51.6	2.033	2091	3.246	1255	1.948	1108	1.72	648	1.006	836	1.298
Article 356 - Liquidtight Flexible Nonmetalic Conduit (LFNC-A)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
16	½	16	0.63	201	0.312	121	0.187	107	0.165	62	0.097	80	0.125
21	¾	21	0.825	346	0.535	208	0.321	184	0.283	107	0.166	139	0.214
27	1	26.5	1.043	552	0.854	331	0.513	292	0.453	171	0.265	221	0.342
35	1¼	35.1	1.383	968	1.502	581	0.901	513	0.796	300	0.466	387	0.601
41	1½	40.7	1.603	1301	2.018	781	1.211	690	1.07	403	0.626	520	0.807
53	2	52.4	2.063	2157	3.343	1294	2.006	1143	1.772	669	1.036	863	1.337
Article 350 - Liquidtight Flexible Metal Conduit (LFMC)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
16	½	16.1	0.632	204	0.314	122	0.188	108	0.166	63	0.097	81	0.125
21	¾	21.1	0.83	350	0.541	210	0.325	185	0.287	108	0.168	140	0.216
27	1	26.8	1.054	564	0.873	338	0.524	299	0.462	175	0.27	226	0.349
35	1 ¼	35.4	1.395	984	1.528	591	0.917	522	0.81	305	0.474	394	0.611
41	1 ½	40.3	1.588	1276	1.981	765	1.188	676	1.05	395	0.614	510	0.792
53	2	51.6	2.033	2091	3.246	1255	1.948	1108	1.72	648	1.006	836	1.298
63	2 ½	63.3	2.493	3147	4.881	1888	2.929	1668	2.587	976	1.513	1259	1.953
78	3	78.4	3.085	4827	7.475	2896	4.485	2559	3.962	1497	2.317	1931	2.99
91	3 ½	89.4	3.52	6277	9.731	3766	5.839	3327	5.158	1946	3.017	2511	3.893
103	4	102.1	4.02	8187	12.692	4912	7.615	4339	6.727	2538	3.935	3275	5.077
129	5	—	—	—	—	—	—	—	—	—	—	—	—
155	6	—	—	—	—	—	—	—	—	—	—	—	—
Article 344 - Rigid Metal Conduit (RMC)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
16	½	16.1	0.632	204	0.314	122	0.188	108	0.166	63	0.097	81	0.125
21	¾	21.2	0.836	353	0.549	212	0.329	187	0.291	109	0.17	141	0.22
27	1	27	1.063	573	0.887	344	0.532	303	0.47	177	0.275	229	0.355
35	1 ¼	35.4	1.394	984	1.526	591	0.916	522	0.809	305	0.473	394	0.61
41	1 ½	41.2	1.624	1333	2.071	800	1.243	707	1.098	413	0.642	533	0.829
53	2	52.9	2.083	2198	3.408	1319	2.045	1165	1.806	681	1.056	879	1.363
63	2 ½	63.2	2.489	3137	4.866	1882	2.919	1663	2.579	972	1.508	1255	1.946
78	3	78.5	3.09	4840	7.499	2904	4.499	2565	3.974	1500	2.325	1936	3
91	3 ½	90.7	3.57	6461	10.01	3877	6.006	3424	5.305	2003	3.103	2584	4.004
103	4	102.9	4.05	8316	12.882	4990	7.729	4408	6.828	2578	3.994	3326	5.153
129	5	128.9	5.073	13050	20.212	7830	12.127	6916	10.713	4045	6.266	5220	8.085
155	6	154.8	6.093	18821	29.158	11292	17.495	9975	15.454	5834	9.039	7528	11.663
Article 352 - Rigid PVC Conduit (PVC), Schedule 80
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
16	½	13.4	0.526	141	0.217	85	0.13	75	0.115	44	0.067	56	0.087
21	¾	18.3	0.722	263	0.409	158	0.246	139	0.217	82	0.127	105	0.164
27	1	23.8	0.936	445	0.688	267	0.413	236	0.365	138	0.213	178	0.275
35	1 ¼	31.9	1.255	799	1.237	480	0.742	424	0.656	248	0.383	320	0.495
41	1 ½	37.5	1.476	1104	1.711	663	1.027	585	0.907	342	0.53	442	0.684
53	2	48.6	1.913	1855	2.874	1113	1.725	983	1.523	575	0.891	742	1.15
63	2 ½	58.2	2.29	2660	4.119	1596	2.471	1410	2.183	825	1.277	1064	1.647
78	3	72.7	2.864	4151	6.442	2491	3.865	2200	3.414	1287	1.997	1660	2.577
91	3 ½	84.5	3.326	5608	8.688	3365	5.213	2972	4.605	1738	2.693	2243	3.475
103	4	96.2	3.786	7268	11.258	4361	6.755	3852	5.967	2253	3.49	2907	4.503
129	5	121.1	4.768	11518	17.855	6911	10.713	6105	9.463	3571	5.535	4607	7.142
155	6	145	5.709	16513	25.598	9908	15.359	8752	13.567	5119	7.935	6605	10.239
Articles 352 and 353 - Rigid PVC Conduit (PVC), Schedule 40, and HDPE Conduit (HDPE)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
16	½	15.3	0.602	184	0.285	110	0.171	97	0.151	57	0.088	74	0.114
21	¾	20.4	0.804	327	0.508	196	0.305	173	0.269	101	0.157	131	0.203
27	1	26.1	1.029	535	0.832	321	0.499	284	0.441	166	0.258	214	0.333
35	1 ¼	34.5	1.36	935	1.453	561	0.872	495	0.77	290	0.45	374	0.581
41	1 ½	40.4	1.59	1282	1.986	769	1.191	679	1.052	397	0.616	513	0.794
53	2	52	2.047	2124	3.291	1274	1.975	1126	1.744	658	1.02	849	1.316
63	2 ½	62.1	2.445	3029	4.695	1817	2.817	1605	2.488	939	1.455	1212	1.878
78	3	77.3	3.042	4693	7.268	2816	4.361	2487	3.852	1455	2.253	1877	2.907
91	3 ½	89.4	3.521	6277	9.737	3766	5.842	3327	5.161	1946	3.018	2511	3.895
103	4	101.5	3.998	8091	12.554	4855	7.532	4288	6.654	2508	3.892	3237	5.022
129	5	127.4	5.016	12748	19.761	7649	11.856	6756	10.473	3952	6.126	5099	7.904
155	6	153.2	6.031	18433	28.567	11060	17.14	9770	15.141	5714	8.856	7373	11.427
Article 352 - Type A, Rigid PVC Conduit (PVC)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
21	¾	23.1	0.91	419	0.65	251	0.39	222	0.345	130	0.202	168	0.26
27	1	29.8	1.175	697	1.084	418	0.651	370	0.575	216	0.336	279	0.434
35	1 ¼	38.1	1.5	1140	1.767	684	1.06	604	0.937	353	0.548	456	0.707
41	1 ½	43.7	1.72	1500	2.324	900	1.394	795	1.231	465	0.72	600	0.929
53	2	54.7	2.155	2350	3.647	1410	2.188	1245	1.933	728	1.131	940	1.459
63	2 ½	66.9	2.635	3515	5.453	2109	3.272	1863	2.89	1090	1.69	1406	2.181
78	3	82	3.23	5281	8.194	3169	4.916	2799	4.343	1637	2.54	2112	3.278
91	3 ½	93.7	3.69	6896	10.694	4137	6.416	3655	5.668	2138	3.315	2758	4.278
103	4	106.2	4.18	8858	13.723	5315	8.234	4695	7.273	2746	4.254	3543	5.489
129	5	—	—	—	—	—	—	—	—	—	—	—	—
155	6	—	—	—	—	—	—	—	—	—	—	—	—
Article 352 - Type EB, Rigid PVC Conduit (PVC)
Metric Designator	Trade Size	Nominal Internal Diameter		Total Area 100%		60%		1 Wire 53%		2 Wires 31%		Over 2 Wires 40%
Metric Designator	Trade Size	mm	in	mm²	in²	mm²	in²	mm²	in²	mm²	in²	mm²	in²
21	¾	—	—	—	—	—	—	—	—	—	—	—	—
27	1	—	—	—	—	—	—	—	—	—	—	—	—
35	1 ¼	—	—	—	—	—	—	—	—	—	—	—	—
41	1 ½	—	—	—	—	—	—	—	—	—	—	—	—
53	2	56.4	2.221	2498	3.874	1499	2.325	1324	2.053	774	1.201	999	1.55
63	2 ½	—	—	—	—	—	—	—	—	—	—	—	—
78	3	84.6	3.33	5621	8.709	3373	5.226	2979	4.616	1743	2.7	2248	3.484
91	3 ½	96.6	3.804	7329	11.365	4397	6.819	3884	6.023	2272	3.523	2932	4.546
103	4	108.9	4.289	9314	14.448	5589	8.669	4937	7.657	2887	4.479	3726	5.779
129	5	135	5.316	14314	22.195	8588	13.317	7586	11.763	4437	6.881	5726	8.878
155	6	160.9	6.336	20333	31.53	12200	18.918	10776	16.711	6303	9.774	8133	12.612