Reference · NEC 2023
NEC Tables 1, 4, 5
Table 1 — Fill limits
| Conductors | Max fill |
|---|---|
| 1 | 53% |
| 2 | 31% |
| 3+ | 40% |
| Nipple ≤24″ | 60% |
Table 4 — Conduit areas (in², 100%)
Every trade size Table 4 lists, straight from our calculator dataset. “—” means the NEC lists no row for that size.
| Size | EMT | IMC | RMC | PVC Sch 40 | PVC Sch 80 | FMC | LFMC | LFNC-B | ENT | HDPE |
|---|---|---|---|---|---|---|---|---|---|---|
| 3/8″ | — | — | — | — | — | 0.116 | 0.192 | 0.192 | — | — |
| 1/2″ | 0.304 | 0.342 | 0.314 | 0.285 | 0.217 | 0.317 | 0.314 | 0.314 | 0.285 | 0.285 |
| 3/4″ | 0.533 | 0.586 | 0.549 | 0.508 | 0.409 | 0.533 | 0.541 | 0.541 | 0.508 | 0.508 |
| 1″ | 0.864 | 0.959 | 0.887 | 0.832 | 0.688 | 0.817 | 0.873 | 0.873 | 0.832 | 0.832 |
| 1-1/4″ | 1.496 | 1.647 | 1.526 | 1.453 | 1.237 | 1.277 | 1.528 | 1.528 | 1.453 | 1.453 |
| 1-1/2″ | 2.036 | 2.225 | 2.071 | 1.986 | 1.711 | 1.858 | 1.981 | 1.981 | 1.986 | 1.986 |
| 2″ | 3.356 | 3.63 | 3.408 | 3.291 | 2.874 | 3.269 | 3.246 | 3.246 | 3.291 | 3.291 |
| 2-1/2″ | 5.858 | 5.135 | 4.866 | 4.695 | 4.119 | 4.909 | 4.881 | — | — | 4.695 |
| 3″ | 8.846 | 7.922 | 7.499 | 7.268 | 6.442 | 7.069 | 7.475 | — | — | 7.268 |
| 3-1/2″ | 11.545 | 10.584 | 10.01 | 9.737 | 8.688 | 9.621 | 9.731 | — | — | 9.737 |
| 4″ | 14.753 | 13.631 | 12.882 | 12.554 | 11.258 | 12.566 | 12.692 | — | — | 12.554 |
| 5″ | — | — | 20.212 | 19.761 | 17.855 | — | — | — | — | — |
| 6″ | — | — | 29.158 | 28.567 | 25.598 | — | — | — | — | — |