ICC ECS - Electrical Code Compliance, Inspection, and Plan Review
What this exam tests
ICC ECS-level electrical certification assumes you can read an installation the way an inspector or plans examiner does. Items are scenario-based: you are shown or described a condition and must decide whether it complies and which rule controls. The scope covers the electrical provisions of the International Residential Code and NFPA 70 (NEC) as locally amended, plus the administrative Chapter 1 duties - when a permit is required, when rough-in must be inspected before concealment, and what a final inspection must verify. Expect weight on services and feeders, wiring methods, boxes, grounding and bonding, overcurrent protection, and dwelling receptacle/GFCI/AFCI rules.
Core rules that drive most answers
- Small-conductor limits: 14 AWG copper is capped at 15 A, 12 AWG at 20 A, and 10 AWG at 30 A, regardless of what the 90 °C ampacity column shows.
- Terminations cap usable ampacity: a 90 °C conductor is only good for derating; the circuit ampacity is limited by the lowest-rated component in the chain - conductor, lug, or equipment.
- Box fill: count each insulated conductor; all equipment grounding conductors together count as one; add one per internal clamp or support fitting; add two for each receptacle yoke, valued at the largest conductor in the box.
- Grounding: the grounding electrode conductor lands at the service. Downstream, grounded and grounding conductors stay separate on the load side of the service disconnecting means.
- Working space: 30 in. wide, 36 in. deep, 6 ft 6 in. high at equipment likely to need servicing.
Worked example: box fill
Two 14/2 NM cables (two insulated conductors plus a bare ground each) enter a 4 in. × 4 in. × 2 1/8 in. box, listed at 30.3 in³, containing one receptacle; no internal clamps. Volume per 14 AWG is 2.0 in³. Insulated conductors: 4 × 2.0 = 8.0. Equipment grounds, all counted as one: 1 × 2.0 = 2.0. Receptacle yoke: 2 × 2.0 = 4.0. Total 14.0 in³ against 30.3 in³ available - compliant, with 16.3 in³ to spare.
Traps that cost marks
Mixing up grounded (neutral) and grounding (equipment ground) terminology; sizing from the 90 °C column while the lugs are 75 °C; forgetting the two-conductor allowance per receptacle; assuming AFCI protection stops at bedrooms when the rule now reaches most dwelling branch circuits; and measuring working-space depth from the wall rather than from the face of the equipment.