Electrical conduit
Also known as: EMT, Romex alternative, wiring conduit
Tube or pipe protecting electrical wiring. Required in commercial installations and exposed-to-damage residential locations. Material affects cost, flexibility, and code compliance.
Conduit protects electrical wiring from physical damage, moisture, and environmental hazards. Common types: EMT (electrical metallic tubing — thin-wall steel, most common in commercial), PVC (rigid plastic, used outdoors and in concrete), flexible metal conduit (FMC, used for short runs and in tight spaces), liquid-tight flexible (LFMC, for outdoor or wet equipment connections), and rigid metal conduit (RMC, heavy-duty, often used in industrial).
Residential wiring inside finished walls typically uses NM cable (Romex) without conduit. Conduit is required for: exposed wiring in basements/garages where physical damage is possible, all wiring in commercial buildings, outdoor wiring (UV and moisture protection), wiring run through concrete, and any wiring subject to cutting/drilling (above suspended ceilings).
Conduit fill — how many wires can fit in a given conduit size — is governed by NEC tables and is a frequently-violated requirement. Over-filled conduit causes heat buildup, voltage drop, and code violations. Sizing the right conduit for the wire count and types is foundational electrical-code competency.
Related terms
GFCI (Ground Fault Circuit Interrupter)
Outlet or breaker that detects current leakage to ground and trips the circuit within milliseconds. Required by code in wet locations (kitchens, baths, outdoors).
AFCI (Arc Fault Circuit Interrupter)
Breaker that detects dangerous electrical arcs and trips the circuit. Required by NEC in most residential bedrooms, living areas, and habitable rooms since 2014.
Journeyman vs Master electrician license
Two tiers of state electrical licensure. Journeyman: can perform electrical work under supervision. Master: can pull permits, design installations, supervise journeymen, run an electrical business.