Why The National Electrical Code (NFPA 70) is a building/wiring safety standard, not an FCC rule. It specifies things like conductor sizes, overcurrent protection, grounding and bonding, and safe installation practices, so for a ham station it governs the AC wiring, service entrance, station ground and lightning protection. Bandwidth, modulation and RF exposure limits come from FCC Part 97, not the NEC.
Watch out RF exposure is the tempting pick because it sounds like a safety topic, but human RF exposure limits come from the FCC (Part 97 and the OET Bulletin 65 guidance derived from IEEE/NCRP), not the electrical code.
NEC = wires and grounds (AC safety); FCC Part 97 = signals and RF exposure.