Quick Hits

📱 EPISODE 2 — Article 358 (Part 2 of 2)

Sizing, Threading, Securing & Grounding — Article 358 Complete!

SLIDE 1 — Sizing & Bends
📏 SIZE LIMITS (358.20)

Minimum: trade size ½ (Exception: trade size ⅜ for motor lead enclosures per 430.245(B))
Maximum: trade size 6

🔄 BENDS (358.24)
Bend radius per Chapter 9, Table 2 — specifically the "one-shot and full shoe benders" reference. Max 360° total bends per run between pull points.

SLIDE 2 — Reaming & Threading — KEY DIFFERENCE FROM RMC/IMC
🔧 EMT DOES NOT GET THREADED (358.28)

Reaming: all cut ends must be reamed/finished to remove rough edges — same as other conduits.

⚠️ THREADING: EMT SHALL NOT BE THREADED. This is a fundamental difference from RMC and IMC — EMT relies on couplings/connectors, not field threading.

Exception: EMT with FACTORY threaded integral couplings (complying with 358.100) IS permitted.

SLIDE 3 — Securing & Supporting (358.30)
🛠️ SIMILAR FRAMEWORK TO RMC/IMC

Secured:
🔹 At intervals NOT exceeding 10 ft (3m)
🔹 Within 3 ft (900mm) of each termination

Exception 1: fastening can extend to 5 ft where structural members don't allow 3 ft.
Exception 2: unbroken lengths CAN be fished in concealed/finished work where securing is impracticable.

Horizontal runs supported through framing openings at ≤10 ft intervals, secured within 3 ft of termination points — permitted.

SLIDE 4 — Couplings, Grounding, Construction + Final Exam Question
🔗 COUPLINGS/CONNECTORS (358.42)

Must be made tight: CONCRETE-TIGHT type when buried in masonry/concrete; WET-LOCATION-LISTED fittings for wet areas.

🌎 GROUNDING (358.60): EMT IS permitted as an equipment grounding conductor.

🏗️ CONSTRUCTION (358.100): steel with protective coatings, aluminum, OR stainless steel.

🏷️ MARKING (358.120): every 10 ft (3m) per 110.21(A).

🎉 That's a wrap on Article 358 — Electrical Metallic Tubing!

🧠 FINAL EXAM QUESTION FOR ARTICLE 358

Q: Per 358.28(B), is EMT permitted to be threaded in the field?

A) Yes, always
B) No — EMT shall not be threaded, except for factory threaded integral couplings
C) Only trade sizes 2 in. and larger
D) Only stainless steel EMT can be threaded

(Drop your final answer 👇)

Article 358 = DONE ✅

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