Special Occupancies, Special Conditions, and Special Equipment (NEC Chapters 5-6)
Chapters 5 and 6: special occupancies, conditions, and equipment
Chapter 5 addresses places. Hazardous (classified) locations (Articles 500–506) turn on class, division or zone, and group - questions ask which wiring method or enclosure marking is permitted, so learn the class/division logic before memorizing details. Other high-yield articles: 511 commercial garages, 514 motor fuel dispensing, 517 health care facilities, 547 agricultural buildings, 555 marinas, 590 temporary installations, and 680 swimming pools, fountains, and similar installations.
Chapter 6 addresses equipment. Know these: 620 elevators, 625 electric vehicle supply equipment, 680 pools (680.26 equipotential bonding of pool shells, metal parts, and the 3 ft perimeter surface using 8 AWG solid copper), 690 solar photovoltaic systems, 695 fire pumps, 700 emergency systems, 701 legally required standby, 702 optional standby, and 705 interconnected power production sources.
Worked example (PV): a string with a short-circuit current of 10 A requires overcurrent devices rated at least 125 percent of that current per 690.8, and conductor ampacity at 125 percent of the result, so the design uses 12.5 A for the device and 15.6 A for conductor ampacity.
Traps: pool bonding is not the same as grounding - the equipotential grid serves a different purpose; 700.10 requires emergency circuits to be kept separate from normal wiring and protected from fire; special-occupancy articles override the general Chapter 3 method for the same installation.