Where the physical damage rule lives in the 2026 code, and what an old tab costs you in the exam room

The address, and what it costs

Protection against physical damage for Chapter 3 wiring methods is NEC 300.6 in the 2026 edition. It was 300.4 in the book most people studied from, and on its own that is a cheap correction.

The expensive part is what occupies the old number now. NEC 300.4 in the 2026 book is Limitations, capping a wiring method by voltage and temperature, and this cycle it picked up a subsection headed Damaged Conductors and Wiring Methods at NEC 300.4(C), which calls for wiring ruined by overheating, fire, corrosive influences or water to be replaced.

Read that trap slowly, because 2026 made it worse. The number in your memory is occupied, it sits in the article you wanted, and it carries a heading with the word damaged in it. An empty number costs a few seconds and says loudly that something changed. A number answering a neighboring question costs you the time to read it, decide it does not govern, doubt that, read it again and start over. On an item pitched at a little over two minutes, that is the item.

The two rules do genuinely different work. NEC 300.6 keeps damage from reaching a method that is currently fine, and NEC 300.4(C) says what happens to one already ruined. A cable about to meet a drywall screw is the first, and a cable that has been cooked or flooded is the second.

How the bank tests this

Six of the 500 items in our bank turn on physical damage, and all six sit in the wiring methods and installations area, which holds 140 of the 500 in total. They come in four shapes, and knowing the shapes is worth more than rereading the section.

• A straight address question. One item asks where the 2026 edition places the requirement, and the wrong answers are 300.4, 300.5 and 310.6. The bank's note on 300.4 says it plainly: the pre-2026 number, now occupied by a different rule.
• A distance question. A cable through a bored hole in a wood stud, where the plate turns on the distance from the edge of the stud to the nearest edge of the hole. The wrong answers offer the cable type, the circuit voltage and whether the wall is load bearing, and every one of those sounds like a reason.
• A two-moves question, graded at the easiest level in the bank. A run along a warehouse wall where forklifts work, and the two moves the code allows are a method suited to it or protection for the one you would prefer.
• A misapplied-plate question. Exposed cable in an unfinished basement, where one wrong answer carries the steel plate over from the bored hole rule into a support question.

The fourth shape is the one worth practicing. The steel plate is the most memorable object in this part of the code, so it turns up as bait in items about support and about cable tray. If an option offers a plate, check that the question was about something a plate protects against.

There is no offset to carry

The 2026 edition ran a common template through the book. Listing requirements went to the second section of an article and reconditioned equipment to the third, and where those slots were occupied the sections behind them slid down. Article 300 is the clean case, and the book falsifies any general offset in two directions at once. Article 312 moved by three. Article 314 gained a listing section at the front, moved nonmetallic boxes, and then stopped dead, so box fill is still 314.16.

Three, then two, then nothing, and inside Article 314 the offset changes partway down the article. A candidate who adds two and finds real text at the result cannot tell whether the answer is one section short or two sections long, which is a worse position than finding a blank page. What held this cycle is the article number, so the move that works is to open the article you already know and read down its section titles. That takes fifteen seconds on a tabbed article, and the bank tests exactly this failure at 312.9, where wire-bending space moved and the old 312.6 kept real text on cabinets and enclosures.

Confirm an address from inside the book

The code cross-references itself constantly, and a cross-reference printed in the 2026 edition carries a current address whether or not your memory does. Two worked examples, from different articles, which is what makes the habit trustworthy here. The box fill rules explain how to count a long loop of unbroken conductor by comparing it against the minimum length of free conductor at a box, and in the 2026 book that comparison points at 300.16. Turn there and you are reading the free conductor rule, which was 300.14 last cycle. Separately, the cable entry rule for cabinets sends you to 300.14 for what a complete raceway system means, and that rule was 300.12 in the previous edition.

Two cross-references, written by two different panels, both landing two numbers above the 2023 address, both printed inside the book on your desk. When you doubt a number, find something in the 2026 book that cites it and read where the citation lands. That is evidence from the document your paper is written against, which beats any published summary, this page included.

What the section actually holds

The opening sentence is short and general: where a wiring method is subject to physical damage, it gets protected. The items come from everything after it, which is carpentry.

• Bored holes through wood framing, with a stated distance from the nearest edge of the member, and a steel plate or bushing where that distance cannot be held.
• Notches cut into framing, where the plate goes across the notch and goes on before the finish does.
• Cable and nonmetallic tubing through metal framing members, where the cut edge of a punched stud gets listed bushings or grommets.
• Cable and raceway run parallel to a framing member or a furring strip, which is answered by a clearance from the face.
• Cable or raceway laid in a shallow groove about to be covered by wallboard, siding or a similar finish.
• Wiring in or under roof decking, where the 2026 edition broadened the clearance beyond metal corrugated decking and rewrote it around wiring methods and materials at NEC 300.6(E).
• Insulated fittings where a raceway carrying 4 AWG or larger conductors enters a cabinet, box or enclosure.

Notice the organizing idea under that list. The section sorts by what the wiring passes through, so an item naming a cable type may still belong here. If the scenario turns on a stud, a joist, a plate or a deck, you are in Article 300, and notes on roof decking that still say corrugated describe a narrower rule than the one your paper uses.

The answer that beats a plate

Here is the trap sitting on top of the trap. A scenario describes a run somewhere it will get hit, and two of the options both sound like code: add protection of some named kind, or use a different method entirely.

The general damage rule is one of two rules in play. Method articles carry their own restrictions, and several keep a method out of locations subject to physical damage outright, so a plate rescues nothing there. Read the scenario for two things: what protection would fix it, and whether this method was permitted in that location to begin with.

The bank carries the same idea in an agricultural building, where conduit and boxes sit at a height livestock can push against. The wrong answers name a material and a protective device, and the article answers with physical protection or a location out of reach. That is one place this subject crosses into agricultural building wiring.

Two neighbors answering different questions

Article 300 also carries protection against corrosion and deterioration, which is a chemical problem where this is a mechanical one, and an item will describe a damp corrosive location to see which you reach for. Watch the number on that one especially. In the 2023 book, 300.6 was the corrosion section. In the 2026 book, 300.6 is the damage section. If the number 300.6 makes you think corrosion, your memory is exactly one edition old. Corrosion also pulls in location classification, since the cable article answering a damp corrosive run splits on a single letter in the type designation.

The grounding electrode conductor keeps its own damage rule at NEC 250.64(B). It turns on the size of the conductor and on whether it is exposed to physical damage, which is a different test from anything in Article 300, and the protective methods it names are its own. A grounding electrode conductor running down an exterior wall gets answered from the grounding article and never from here.

Outdoor equipment sits in a third place again. The bank puts a disconnect at the edge of a parking lot, where Article 110 asks for protection from vehicular traffic and 300.6 carries the parallel requirement for the wiring. The matching question set works the same subject from the code side, with the section text and the worked arithmetic, at the physical damage question set.

What a Texas candidate should do

Texas adopts the 2026 National Electrical Code effective 1 September 2026 under 16 TAC 73.100, and the PSI bulletin updated 9 July 2026 states in capitals that the examinations reference that edition from that date. So the address on this page is the one your paper is written against, and the one in your memory probably belongs to the book on the truck.

Four things to do with the book. Open Article 300 and read the section titles in order, ignoring the text, which resets the map you carry in about a minute. Move any tab reading 300.4 for damage to 300.6 and relabel it. Run the same audit on Articles 312 and 314. Then read the uses-not-permitted list in the method articles you use most, since that list overrules this section.

The same cutover carries a licensing consequence that catches people in September. Your four hours of continuing education under 16 TAC 73.25(b)(1) follow the code as adopted and the rule names no year, so from 1 September 2026 a course taught entirely on 2023 content covers an edition Texas no longer enforces. Whether four hours completed on 2023 content before that date still satisfy a renewal falling after it is a question the rule leaves open, and it is worth putting to the department before you rely on the answer you would prefer. See continuing education and which code edition applies.

Questions people ask

What section covers protection against physical damage in the 2026 NEC?

NEC 300.6 in the 2026 edition, moved down from 300.4 where it sat in the 2023 book. The old address is occupied now by Limitations, which caps a wiring method by voltage and temperature, and that section picked up a subsection this cycle headed Damaged Conductors and Wiring Methods at 300.4(C). So the number you may remember carries real text, in the article you wanted, under a heading with the word damaged in it. The two rules answer different questions: 300.6 keeps damage from reaching a method that is fine, and 300.4(C) covers a method already ruined.

Is there a fixed offset for finding 2023 sections in the 2026 book?

No, and building one is the mistake this cycle punishes hardest. Article 300 moved by two. Article 312 moved by three, so cable entry for cabinets went from 312.5(C) to 312.8(C) and wire-bending space went from 312.6 to 312.9. Article 314 gained a listing section at the front, moved nonmetallic boxes from 314.3 to 314.5, and then stopped, leaving box fill at 314.16 and pull and junction boxes at 314.28. The article numbers held, so the reliable move is to open the article you know and read down its section titles.

What decides whether a bored hole through a stud needs a steel plate?

The distance from the edge of the framing member to the nearest edge of the hole. The rule is written as a minimum distance from the face of the member, and below that distance a steel plate or equivalent protection goes on. The bank builds wrong answers out of three plausible substitutes: the cable type, on the theory that armored cable carries its own protection; the circuit voltage, on the theory that more voltage needs more protection; and whether the wall is load bearing, which is a building code question about how far a stud may be bored.

When does protection fail to fix a physical damage problem?

When the method was kept out of that location in the first place. The general rule at 300.6 is one of two rules in play, since each Chapter 3 method article carries its own uses-permitted and uses-not-permitted lists, and several of them bar a method from locations subject to physical damage outright. Where an article says the method does not belong there, adding a plate or a sleeve rescues nothing. So an item describing a run somewhere it will get hit is asking two questions at once, and the uses-not-permitted list settles the second one.

Does the code define what counts as subject to physical damage?

It sets no measurement, and the judgment belongs to the authority having jurisdiction, which unsettles candidates who want a number. The exam works around that by describing cases nobody argues about, such as a run at bumper height in a parking garage, a warehouse aisle where pallets get moved, or exposed work in a shop where material is stacked. An item asking you to weigh a marginal case would have no defensible key, so it will not appear. What can be tested is what you do once the condition is established, which puts you back in 300.6 and in the method article.