At one time, the National Electrical Code (NEC) contained two Articles you won’t find as of the 2020 revision: Art. 280 (surge arrestors) and Art. 285 (transient voltage surge suppressors or TVSS).
Part II of Art. 210 of the 2020 National Electrical Code provides the requirements for rating branch circuits. It’s pretty simple, really. You rate them per the maximum permitted ampere rating (or ...