Special Occupancies, Special Locations, and Special Equipment
Classified and special locations
Special occupancies include hazardous (classified) locations, health care facilities, places of assembly, commercial garages, agricultural buildings, marinas, and pools. Hazardous locations are classified by class, division or zone, and gas or dust group; equipment must be listed for the specific atmosphere. Intrinsic safety, explosionproof enclosures, and purged systems are different protection techniques.
Equipment and locations
Know the special rules for pools and spas, bathrooms, kitchens, garages, outdoors, electric vehicle charging, solar PV, energy storage, signs, welders, cranes, and elevators. GFCI protection is required in many wet and dwelling locations, and equipotential bonding is critical around pools. Photovoltaic systems have unique conductor identification and rapid-shutdown requirements.
Traps
Do not apply ordinary location equipment in a classified area or assume a NEMA 4 enclosure is explosionproof. Pool questions often test the bonding grid and the required distance from the water's edge. PV questions may confuse DC and AC sides, and EV questions often hinge on GFCI or disconnect requirements.
Worked example
A pool pump located near the water must be bonded to the equipotential bonding grid with a solid copper conductor, and the bonding conductor must connect to all metal parts of the pool structure and associated equipment. Rule of thumb: in special locations, first identify the classification and the required protection technique, then select equipment.