Checked against primary sources 2026-08-24

Four numbers that still exist and now mean something else

A vacated number costs you a few seconds. A reused number can cost you an afternoon, because the text at the old address is real code and it reads as though it belongs.

The list

Both columns below are sourced separately. What the number used to mean is checked against the older edition, what it means now is checked against the new one, and a row does not go up until both ends hold.

Article 720 is the one row with a loose end. The number now carries a subject unrelated to the one it used to carry, and where the old under-50-volt material ended up is not something we have verified. Rather than guess at it, this page leaves that unsaid.

Two article numbers, two section numbers, two different causes

The top two rows and the bottom two rows got here by different routes, and knowing which route you are looking at tells you how much else to distrust.

The article numbers were freed by subjects moving out. Energy management left Chapter 7 for Chapter 1 and the under-50-volt material left 720, and both numbers were refilled during the rebuild of the limited-energy and communications articles in the same cycle. That is a one-off event in one corner of the book. Nothing about it predicts anything anywhere else.

The section numbers were pushed off their content by a pattern that ran through the whole edition. 450.3 and 300.4 are not curiosities, they are two visible outcomes of a template you will meet again in other articles, which is what the next section is about.

One template, four different outcomes

Many articles in this edition were given the same two openers, a Listing Requirements section at .2 and a Reconditioned Equipment section at .3, and the reason is a drafting rule rather than anything about electricity. The panel that owns the photovoltaic article puts it in one line, in the second revision that retitles the listing section there.

Title is changed to comply with the NEC Style Manual for this section.

NFPA code-making panel 4, second revision 7576

What that did to the numbers behind those two slots depends entirely on what was in them already, and it produced at least four different answers in this edition.

• The slots were occupied by unrelated content, so everything behind them slid. Article 450 is the plainest case: panel 9 filed the two template headings as new sections inserted after 450.1, they hold nothing but their titles, and transformer overcurrent protection sits at 450.5 with its two tables. Article 300 shifted by two and Article 312 by three.
• The slot already held that kind of rule, so it was retitled where it stood. In Article 690 the section at .2 was headed Equipment and carried the article's own listing rule for photovoltaic gear, the list of things to be listed or field evaluated. In 2026 the same section is headed Listing Requirements over the same kind of list, and 690.9 and 690.12 kept the numbers they had.
• The slots were empty, so the template dropped in and nothing else moved. Article 410 took both new headings and left the rest of its numbering alone, which is why the horticultural and germicidal lighting sections at the far end of that article are still where they were.
• The template did not run at all. Panel 17's second draft adds no Listing Requirements section and no Reconditioned Equipment section to Article 422, and renumbers nothing in it.

So the offset for this edition is not two, and it is not three. It is a property of the article you happen to be looking up, and the only way to know it is to look at the front of that article in the book being enforced.

Article 312 moved as a block, which is a different trap

Deflection of conductors, and the wire-bending space that goes with it, is at 312.9 in the 2026 edition, having been at 312.6. Nothing about the requirement changed. The whole article slid three places when the two template headings went in at 312.2 and 312.3.

Panel 8's second draft shows the slide at two anchors. The rules about conductors entering a cabinet or cutout box, which are 312.5 in the 2023 book, print at 312.8. The splices, taps and feed-through material, which is 312.8 in the 2023 book, prints at 312.11. Three places at both ends of the article, which is what puts the old 312.6 at 312.9.

So 312.6 is occupied rather than empty. We have not read what sits there and are not going to tell you what it says.

That is the shape to watch for. A number you memorized inside one of these articles is more likely to be three off than to be gone, and three off lands you inside the same article, on rules about the same enclosure, written in the same voice.

Checking a number, one way that works

1. Look the subject up by title in the table of contents of the book being enforced. The title traveled with the content in every case on this page. The number did not.
2. Check both ends before you rely on it. Does the number carry the subject you expect, and does the subject you expect carry that number. The index answers the second one. Only turning to the section answers the first.
3. Where the number is going into a document somebody else will read, write the title next to it. A title survives an edition change. A bare number might not.

There is one shortcut worth having, and it runs in one direction only. If a document cites the old number for the old subject, 450.3 for transformer overcurrent or 300.4 for physical damage, it was written against the 2023 book or an older one. That much is safe.

The reverse is not. Most numbers exist in both editions, so a citation that matches the 2026 book proves nothing about which book the writer had in front of them. They may have been right about the new edition, or right about the old one, or copying a number out of a document nobody has checked since 2020.

One kind of document breaks the shortcut on purpose, and it is worth naming because you are reading one. Anything written about the renumbering itself pairs the old number with the old subject deliberately, four times over in the table at the top of this page. Check what a document is for before you date it by its citations.

How this list is maintained

This list is not complete, and saying so is more useful than implying it is. It holds what we have verified at both ends, in the parts of the book we have covered so far.

A row goes up when two things are true: we can show what the number carried through the 2023 edition, and we can show what it carries in the 2026 edition, each from a source we can name. A number we suspect has been reused but can only source at one end stays off the page and sits in the notes instead.

When we find another, it goes here with the date. If you find one before we do, the contact page is the fastest way to tell us, and the correction gets logged in public either way.

What this page cites

• NEC 750.1 The 2026 subject at Article 750, which through the 2023 edition was Energy Management Systems. Both ends of that row are sourced separately, which is the rule for every row on this page. source
• NEC 450.5 Overcurrent protection of transformers, 2026 edition, with Tables 450.5(A) and 450.5(B) under it. Second revision 8259 in panel 9's second draft prints 450.2 Listing Requirements reserved and 450.3 Reconditioned Equipment with both subsections reserved. Re-read 24 August 2026. source
• NEC 300.6 Protection against physical damage, 2026 edition. 300.4 is Limitations in the same edition and carries a new subsection on damaged conductors and wiring methods. source
• NEC 720.1 General requirements for limited-energy systems wiring methods and materials, 2026 edition. source
• NEC 312.9 Deflection of conductors and wire-bending space, 2026 edition. Derived from the three-section shift shown at two anchors in panel 8's second draft, which prints Listing Requirements at 312.2 and Reconditioned Equipment at 312.3. source
• NEC 690.2 Listing Requirements in Article 690, retitled from Equipment by second revision 7576 with the committee statement quoted on this page. The sections behind it kept their numbers, which is what makes it the retitled-in-place case rather than a shift. Read 24 August 2026. source
• NEC 410.2 The empty-slot case. Both template headings arrive in Article 410 and no section behind them changes number, which is the single clearest piece of evidence that this edition has no uniform offset. Panel 18's second revision draft. source
• NFPA 70 code-making panel 17, second draft Article 422 takes neither template heading and none of its sections are renumbered, which is the evidence that the template did not reach every article. Read 24 August 2026. source