Free ICC E1 Exam Flashcards

One- and two-family dwellings and townhouses up to 3 stories, limited to 120/240V, single-phase service up to 400 amperes. Anything larger — apartments, commercial buildings — falls under the IBC/NEC instead of the IRC.

IRC Part VIII, Chapters 34-43, is the E1 reference — not a standalone NEC book. The 2024 IRC electrical chapters are adapted from the 2023 NEC (NFPA 70) but reformatted specifically for one- and two-family dwellings.

36 inches of depth, 30 inches of width (or the equipment's width if greater), and 6 ft 6 in of headroom — the '36-30-6.5' working space rule for equipment likely to need service while energized.

Only with approved splicing devices, or by brazing, welding, or soldering with a fusible alloy, then covered with insulation equal to the conductors themselves. A twist of wire wrapped only in tape is a code violation.

6 AWG copper — the GEC portion running to a rod, pipe, or plate electrode never needs to exceed 6 AWG copper, even if the rest of the GEC is sized larger for the overall service.

100 amperes, 3-wire. This is a floor requirement that applies even when the calculated load comes out lower than 100A.

Up to six, per the 'six-handle rule' — no more than six motions of the hand may be needed to disconnect all power to the dwelling, and each disconnect must be marked with its purpose.

2/0 AWG copper (or 4/0 AWG aluminum). The IRC's reduced dwelling-service conductor table allows smaller residential 120/240V service conductors than the general ampacity table would otherwise require.

3 VA per square foot of floor area, based on outside dimensions — but excluding open porches, garages, and unfinished spaces not adaptable for future use.

100% — the first 3,000 VA gets no reduction. VA from 3,001 to 120,000 drops to a 35% demand factor, reflecting that not every load runs simultaneously.

Metal water pipe, a concrete-encased (Ufer) electrode, ground rings, rod/pipe/plate electrodes, and building steel are all bonded together as one system — but interior metal gas piping is never used as a grounding electrode; it is only required to be bonded.

It must be augmented with at least one additional electrode spaced 6 feet apart. Most jurisdictions skip the ohm test entirely and simply install two rods to automatically satisfy the rule.

At least 20 feet of bare 4 AWG copper conductor, OR at least 20 feet of 1/2-inch (or larger) bare steel rebar, encased in at least 2 inches of concrete at the bottom of a footing in direct contact with earth.

The neutral and equipment grounding conductor are bonded together only at the service (main bonding jumper). At every panel downstream — including a detached garage sub-panel fed by a feeder — the neutral and ground must be kept isolated on separate buses.

At least two 20A small-appliance circuits. These circuits may not serve outlets outside those rooms, with narrow exceptions such as a dedicated refrigerator circuit.

One 20A circuit for the laundry area receptacle(s), and one 20A circuit for bathroom receptacles — both are separate from the small-appliance circuits and from each other.

80% maximum — a 20A circuit can carry no more than 16A of continuous load, like baseboard heat or an EV charger. Equivalently, the circuit and its overcurrent device are sized at 125% of a known continuous load.

14 AWG = 15A, 12 AWG = 20A, 10 AWG = 30A. These caps override the general 60/75°C ampacity tables specifically for small residential branch-circuit conductors.

No point along the floor line of any wall space 2 feet or wider may be more than 6 feet from a receptacle — which works out to roughly one receptacle every 12 feet.

No point along the countertop wall line may be more than 24 inches from a receptacle, meaning receptacles end up spaced no more than 48 inches (4 ft) apart. Any countertop section 12 inches or wider triggers the requirement.

When the island's long dimension is 24 inches or greater AND its short dimension is 12 inches or greater — both conditions must be met to trigger the requirement.

At least one GFCI-protected receptacle must be accessible at grade level at both the front and the back of the dwelling, mounted no more than 6-1/2 feet above grade.

Bathrooms and clothes closets — bathrooms due to wet/damp conditions, closets due to easily ignitable stored material. Basements, garages, and laundry rooms are all permitted panel locations.

A means to simultaneously disconnect all ungrounded conductors — satisfied by a 2-pole breaker or handle ties, but NOT by two independent single-pole breakers.

Its own readily accessible disconnecting means, located outside or just inside the building nearest where the feeder enters — so power to that structure can be killed independently of the main service.

40 amperes. Smaller electric ranges under 8-3/4 kW may use a 30A or smaller circuit, but most full-size household ranges exceed that threshold.

It gets no demand-factor reduction — it's counted at 100% of nameplate in the service calculation, since electric heat can run continuously in cold weather. The branch circuit and its overcurrent device are still sized at 125%, since it's also a continuous load.

Divide the total calculated general lighting/receptacle VA load by the circuit's VA rating (120V x 15A = 1,800 VA, or 120V x 20A = 2,400 VA), then round up to a whole number of circuits.

Bathrooms, garages, outdoors, kitchens (all countertop receptacles plus the refrigerator and dishwasher), crawl spaces, unfinished basements, laundry areas, and any receptacle within 6 feet of a sink — the single most-tested E1 topic.

AFCI covers nearly all dwelling living spaces on 120V, 15-/20A circuits — bedrooms, family/living/dining rooms, kitchens, hallways, closets, and laundry areas. GFCI guards against shock in wet or damp areas, while AFCI guards against arc-fault fires in living spaces; bathrooms need GFCI but NOT AFCI.

14 AWG = 2.00 cu in, 12 AWG = 2.25 cu in, 10 AWG = 2.50 cu in per conductor — used to check whether an outlet box has enough volume for its contents.

Two, sized to the largest conductor connected to that device — regardless of whether it's a single or duplex device mounted on the yoke.

Just one total, based on the largest conductor present in the box — no matter how many internal clamps are inside. External clamps outside the box don't count toward fill at all.

The near edge of the hole must be at least 1-1/4 inches from the stud's edge. If that clearance can't be met, a 1/16-inch steel plate (or equivalent) must shield the cable from nail or screw penetration.

Secured at intervals not exceeding 4-1/2 feet, and within 12 inches of most boxes — but within 8 inches for a single-gang nonmetallic box that has no internal cable clamps.

The 60°C column — so 12 AWG copper NM cable is capped at 20A even though its insulation is rated 90°C. This pairs with the small-conductor rule that already caps 12 AWG at 20A.

360 degrees total — the equivalent of four quarter (90°) bends. If more bends are needed to make the run, a pull box must be added.

By at least 1/4 inch of separation, a physical barrier, or installation in a separate raceway or compartment — low-voltage wiring cannot simply lie against line-voltage conductors in the same box without a divider.

50 pounds. Heavier fixtures need independent structural support, and ceiling (paddle) fans always need a box specifically listed for fan support, or independent support, regardless of the fan's weight.

Every habitable room, bathroom, hallway, stairway, attached garage, and the exterior side of outdoor entrances. In habitable rooms other than kitchens and bathrooms, a switched receptacle can substitute for a fixed lighting outlet.

Six or more risers — lighting must be controlled from a wall switch at each floor level and landing with an entryway, so occupants can turn the lights on or off from either end.

12 inches of clearance for surface-mounted fixtures, 6 inches for recessed fixtures with a fully enclosed lamp. Open-lamp incandescent fixtures are prohibited entirely, since stored fabric could contact the bulb.

Wet locations need an 'in-use' (bubble) weatherproof cover that stays weatherproof even with a cord plugged in. Damp locations, like under a covered eave, can use the older snap-flap cover instead.

Primary power from the building's house wiring, a battery backup, and interconnection so that any one alarm activating triggers every alarm in the dwelling.

No more than 20 inches above the countertop surface — this keeps appliance cords a reasonable length and prevents them from dangling loosely over the edge.

Only if it's within 18 inches of the wall. A floor outlet farther than 18 inches from the wall is treated as 'free-standing' and does not help satisfy the 6-ft/12-ft wall spacing requirement.

About 25A: 4,500W / 240V = 18.75A of full-load current, then x 1.25 for the continuous-load factor = 23.4A, which rounds up to the next standard overcurrent device size of 25A.

Fixtures listed 'Type IC' (insulation contact) may touch insulation directly. Non-IC fixtures must stay at least 1/2 inch from insulation and 3 inches from combustibles — mixing these up is a common attic inspection failure.

At least 8 AWG solid copper connecting the pool shell/rebar, deck, metal fittings, forming shells, and equipment within 5 feet of the water. Its purpose is to equalize voltage gradients around the pool, not to provide a fault-current ground path.

Underwater luminaires are capped at 150V maximum; any luminaire over 15V needs GFCI protection; and overhead conductors must clear the water surface by at least 22.5 feet — three distinct numbers frequently tested together.