90.5 Mandatory and permissive rules
What changed in 90.5
Referenced standards must show their dates again, two annexes were dropped, and a new annex previews the planned new layout for the next edition.
Point by point
- Edition dates are back on references to other standards, whether the reference is in the rule text or an informational note.
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- 3 more points on exactly what changed
- The 2023 rule next to the 2026 rule, side by side
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This section across NEC® editions
2020 NEC®No change
This section did not change from 2017 to 2020.
2023 NEC®Revised
The explanatory material rules now say that when the code points to another standard without naming an edition, the latest edition applies.
Open the 2023 page →2026 NEC®RevisedYou're here
Referenced standards must show their dates again, two annexes were dropped, and a new annex previews the planned new layout for the next edition.
More 2026 changes in Article 90
This is a plain-English summary, not the NEC®'s exact wording. Always check the full section in the NEC® edition your area has adopted, plus any local amendments.
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