The Code is arranged in chapters that carry different weight. How do the chapters covering special occupancies, special equipment, and special conditions relate to the general chapters that precede them?
- AThey apply only where the authority having jurisdiction adopts each of them separately
The special chapters are part of the Code as adopted. An inspector does not choose them chapter by chapter.
- BThey restate the general chapters for particular occupancies and never change a general requirement
Restating is exactly what they do not do. The whole reason those chapters exist is that ordinary rules are insufficient in the conditions they address.
- They supplement or modify the general chapters, and they govern wherever they differ from them
- DThey apply only to installations owned by a utility or by a government agency
Ownership has nothing to do with which chapters apply. Special occupancy rules follow the hazard, not the owner.
Why C is correct
The special chapters supplement or modify the general chapters and take precedence over them for the occupancies, equipment, and conditions they cover. Understanding that hierarchy is what lets you resolve an apparent conflict between two rules instead of guessing which one an inspector will cite.
What this question is testing
This checks whether you can navigate the Code as a structured document, which is the core skill an open-book exam measures. It also anticipates every question where two articles seem to disagree.
On the job
This structural rule settles most jobsite arguments about conflicting requirements. When a designer insists that a wiring method is permitted because the wiring methods chapter allows it, the answer for a pool deck, a fuel dispenser, or a health care space is that the special chapter narrows the choice. Knowing the hierarchy also tells you where to look first: read the special article for the occupancy, then fall back to the general chapters for anything the special article leaves alone.
Memory technique
Special chapters trump general chapters on their own turf.
Exam tip
When two rules conflict, ask which chapter each one lives in. The special chapter wins for the installation it describes.
Where to look it up
Article 90, the section on how the Code is arranged. It is one page and it explains the logic behind dozens of exam questions.