NEC Article 358 — EMT (Electrical Metallic Tubing): The NJ Urban Default

NEC 358 governs EMT — Electrical Metallic Tubing, the thin-wall metal conduit that's the default wiring method in Hudson County urban work. NJ's dense urban municipalities (Jersey City, Hoboken, Bayonne) commonly amend their building code to require conduit for all wiring, and EMT is the cheapest, easiest answer.

Where EMT is allowed (358.10):

• Concealed and exposed work in dry, damp, and wet locations
• Direct buried with proper fittings (rigid required for direct burial in most cases — verify with AHJ)
• All voltages

Where EMT is NOT allowed (358.12):

• Where subject to severe physical damage (use RMC instead)
• In hazardous (classified) locations except as permitted
• Embedded in cinder concrete or fill where wet conditions exist

Bend limits (358.24): the total degrees of bends between pull points cannot exceed 360°. Past that, you can't pull conductors. Each 90° bend counts as 90°, even gentle sweeps. So between two boxes you can have a maximum of 4 × 90° bends.

Bend radius: see Table 2 of Chapter 9. For ½" EMT, the minimum bend radius is 4 inches. Tighter bends crack the wall and damage insulation.

Support (358.30): EMT must be securely fastened within 3 ft of every box, cabinet, fitting, or other conduit termination, and supported at intervals of no more than 10 ft. NJ inspectors actually count straps on long horizontal runs.

Conductor fill is governed by NEC Chapter 9 Table 1 (40% for 3+ conductors) and Table 4 (EMT internal area per trade size). The Malfettone Conduit Fill Calculator at /tools/conduit-fill handles this — it has presets for common circuits (15 A, 20 A, 50 A EV, 60 A EV, 200 A feeder) so you can pick the right trade size in 2 seconds.

EMT as ground path (250.118(4)): EMT IS recognized as an equipment grounding conductor when it's properly fitted and bonded. But best practice in residential is to run a separate green EGC anyway — fittings loosen over time, and the green wire is your insurance.

Common EMT trade sizes for residential:

• ½" — most branch circuits up to 20 A
• ¾" — 30-50 A circuits, EV chargers up to 50 A
• 1" — 60-100 A feeders, large EV chargers
• 1¼" to 2" — service-entrance and feeder runs

For Jersey City and Hoboken jobs, plan on EMT from the start — adding it after rough-in fails inspection is expensive. The free Conduit Fill Calculator at /tools/conduit-fill sizes the trade for any conductor mix.