NEC 90.22: informational notes

What NEC 90.22 Covers

NEC 90.22 addresses the role of informational notes inside the National Electrical Code. These notes appear throughout the book directly under specific code sections, marked clearly so you can tell them apart from the rule itself. They explain intent, point you to other standards, or give context that helps you apply the rule correctly.

The key takeaway is simple. Informational notes are not enforceable. They explain. They do not require. If an inspector tries to red tag your work based solely on the language inside an Informational Note, they are stepping outside the enforceable text of the Code.

That said, ignoring them is a mistake. The notes often tell you exactly what the Code Making Panel was thinking when they wrote the rule, and that intent matters when a job goes sideways.

Mandatory vs. Explanatory: The Bright Line

The NEC draws a hard line between what you must do and what is offered as guidance. Mandatory rules use "shall" or "shall not." Permissive rules use "shall be permitted" or "shall not be required." Everything else, including informational notes, tables in fine print, and references to outside standards, falls under explanatory material.

Informational notes are printed in smaller type and labeled "Informational Note" right under the section they explain. They never carry the word "shall." If you see "shall," you are looking at a rule, not a note.

• Mandatory: "Shall" or "shall not" ... enforceable
• Permissive: "Shall be permitted" ... allowable, not required
• Explanatory: Informational Notes ... reference only

How to Spot an Informational Note in the Field

Open any current NEC and flip to a populated article like 210 or 250. You will see paragraphs flagged "Informational Note" or "Informational Note No. 1," "Informational Note No. 2," and so on when more than one applies. The font is smaller. The label is clear.

A common example is the note under NEC 210.8(A) that reminds you GFCI protection is intended to reduce shock hazards, or the notes under NEC 250.4 that point to IEEE standards for grounding theory. You can read them, you can use them to understand the why, but you cannot be cited for not following them.

Field tip: when you are arguing a rough-in with an inspector, quote the section number and the "shall" language directly. If the inspector points at an Informational Note, politely note that the language is explanatory and ask which subsection of the rule itself they are enforcing.

Why Informational Notes Still Matter

Treating notes as filler is how electricians get blindsided. The notes often tell you which other NFPA or IEEE standard fills in the blanks, where the dimensions came from, or what hazard the rule is trying to prevent. That context shapes how a competent inspector reads the rule, and how a designer engineers around it.

For example, an Informational Note under NEC 110.16 points to NFPA 70E for arc flash labeling and PPE. NEC 110.16 itself only requires the field marking. Without the note, you would not know where to look for the labeling and analysis methods that make the rule workable on the job.

Notes also flag updates. When a rule changes between code cycles, the notes often explain what the change addresses, which helps you train apprentices and answer GC questions on site without guessing.

Common Pitfalls

Two mistakes show up over and over. First, electricians cite an Informational Note as if it were a rule and lose the argument when challenged. Second, they skip the notes entirely and miss the cross reference that would have answered their question in thirty seconds.

A clean workflow avoids both. Read the rule first. Note the "shall" language. Then read the Informational Note to pick up references and intent. If the note points to NFPA 79, NFPA 99, IEEE 142, or another standard, decide whether the job actually pulls you into that document or whether the NEC rule alone is sufficient.

1. Find the section in question
2. Identify the mandatory or permissive language
3. Read every Informational Note beneath it
4. Follow cross references only when the work demands it
5. Document your interpretation if there is any ambiguity

Field Workflow for Code Discussions

On a live job, the order matters. When an inspector, a foreman, or an engineer pushes back on your install, anchor the conversation in the enforceable text. Pull up the section. Point to the "shall." If the conversation drifts into "well, the note says...," reset to the rule.

That does not mean the notes are useless during these talks. They are gold for explaining why a rule exists, especially with apprentices or building owners who want a real answer instead of "because the code says so." Use the notes to teach, use the rules to enforce.

Real-world tip: keep a tabbed code book or a fast lookup app on your phone. When a question comes up, read the rule and the notes together before you answer. Off-the-cuff code calls are how callbacks happen.

NEC 90.22 is short, but the discipline it sets up runs through every article in the book. Know what is enforceable. Know what is explanatory. Use both, but never confuse the two.