ElectricalPanels, breakers & overcurrentLevel 22023 NEC

Basement laundry panel

Basement laundry room with a painted block wall. A residential load center has its door swung fully open flat against the wall, with the dead front in place and sixteen positions filled with breakers, including 2-pole breakers in positions 2-4 and 6-8; positions 17 through 20 are empty with their twist-outs intact. The handwritten circuit directory on the inside of the door reads: 1 Lights, 2 Range, 3 Plugs, 4 Range, 5 Kitchen, 6 Dryer, 7 Jake's room, 8 Dryer, 9 Misc, 10 Furnace, 11 blank, 12 Bath, 13 Lts + plugs, 14 Upstairs, 15 ?, 16 Garage, and 17 through 20 blank. A washer and dryer stand to the right with a laundry basket on the floor in front of the washer, and a utility sink is to the left. 150 CIRCUIT DIRECTORY 1234567891011121314151617181920LightsRangePlugsRangeKitchenDryerJake's roomDryerMiscFurnaceBathLts + plugsUpstairs?Garage 15 40 12 20 34 20 30 56 15 78 15 15 910 15 20 1112 20 15 1314 15 20 1516 1718 1920
Basement laundry room, panel door open

What's wrong here?

  1. The directory entries are too vague, and one names an occupant
  2. The empty spaces at the bottom must be marked SPARE on the directory
  3. A circuit directory must be typed or printed, not handwritten
  4. Nothing. This installation is compliant
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Show the answer and the code reference

The answer

The circuit directory is vague, has a blank and a question mark for installed breakers, and describes a circuit by an occupant's name instead of a specific location or use.

Correct choice: 1. The directory entries are too vague, and one names an occupant

408.4(A) requires every circuit and circuit modification to be legibly identified as to its clear, evident and specific purpose or use, in enough detail to distinguish it from all others, and says no circuit may be described in a manner that depends on transient conditions of occupancy. Lights, Plugs and Misc fit half the house, ? and a blank line identify nothing, and Jake's room means nothing once Jake moves out or the house sells. The hazard is real: a wrong guess means someone works on a circuit they think is dead.

How to fix it

Trace every circuit and rewrite the directory with specific, permanent descriptions (for example: NE bedroom receptacles and light, kitchen countertop receptacles left of sink), and mark any unused breaker as spare.

Code references

  • NEC 2023 408.4(A) — Circuit Directory or Circuit Identification

    Every circuit and circuit modification must be legibly identified as to its clear, evident, and specific purpose or use, with enough detail to distinguish each circuit from all others. Spare positions with unused overcurrent devices must be described as such, the directory goes on the face or inside of the panel door, and no circuit may be described in a way that depends on transient conditions of occupancy.

    Drills citing 408.4(A)
  • NEC 2023 110.22(A) — Identification of Disconnecting Means, General

    Each disconnecting means must be legibly marked to indicate its purpose unless it is located and arranged so the purpose is evident, and the marking must be durable enough to withstand the environment.

    Drills citing 110.22(A)

2026 NEC:same rule and number. No 2026 change to 408.4(A) turned up; the last substantive revision found was the 2023 reorganization into a list with symbols and abbreviations, so the directory rule appears unchanged but was not confirmed against the 2026 text. Confidence: low

Minnesota

MN adopts the NEC rule as writtenConfidence: high

Minnesota adopts the NEC by reference without amendment (Minn. Rules 1315.0200; Minn. Stat. 326B.35), so 408.4(A) applies as published. The 2023 NEC governs permits filed July 1, 2023 through Aug. 16, 2026; the 2026 NEC governs permits filed on or after Aug. 17, 2026 (exams moved to the 2026 NEC on Sept. 8, 2026). See the 2026 NEC note on this drill.

How Minnesota adopts the NEC

Why the other choices are wrong

  • The empty spaces at the bottom must be marked SPARE on the directory. 408.4(A) requires spare positions that contain unused breakers to be described as spares. Open spaces with no breaker installed don't need a label.
  • A circuit directory must be typed or printed, not handwritten. The Code requires the identification to be legible, clear and specific. Neat handwriting is fine; vague or missing entries are not.
  • Nothing. This installation is compliant. Entries like Lights, Plugs, Misc, ?, a blank, and Jake's room don't let anyone pick the right breaker. 408.4(A) requires each circuit to be identified by its clear, evident and specific purpose.
Code complianceLevel 2 · Journeyman#panel#directory#circuit identification#labeling#basement

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