Knowing the occupancy classification of a building helps the electrician to properly apply rules in the NEC^® to the installation.

NEC Section 700.12 requires sources of emergency power to be installed either in spaces fully protected by approved automatic fire suppression systems (sprinklers, carbon dioxide systems, and so forth) or in spaces with a 1-hour fire rating where located within the following:

(1) Assembly occupancies for more than 1000 persons

(2) Buildings above 75 feet in height with any of the following occupancy classes — assembly, educational, residential, detention and correctional, business, and mercantile.

Although there are no Articles in the NEC^® specifically related to group B (commercial business) occupancies, most commercial business buildings and spaces are typically wired with a NEC^® Chapter 3 wiring method other than nonmetallic sheathed cable Type NM.

Commercial business occupancies can be any size and often have rated fire walls, floors, or ceilings. When wiring in group B occupancies, pay close attention to any fire separation requirements that will affect the type of wiring method used or the method in which electrical boxes are installed into walls or suspended ceilings.

According to IBC Section 304, a Business Group B occupancy includes, among others, the use of a building or structure, or a portion thereof, for office, professional or service-type transactions, including storage of records and accounts.

Group B (Business) occupancies shall include, but not be limited to, the following:

• Airport traffic control towers
• Ambulatory care facilities
• Animal hospitals, kennels and pounds
• Banks
• Barber and beauty shops
• Car wash
• Civic administration
• Clinic, outpatient
• Dry cleaning and laundries: pick-up and delivery stations and self-service
• Educational occupancies for students above the 12^th grade including higher education laboratories
• Electronic data processing
• Food processing establishments and commercial kitchens not associated with restaurants, cafeterias and similar dining facilities not more than 2,500 square feet (232 m²) in area
• Laboratories: testing and research
• Motor vehicle showrooms
• Post offices
• Print shops
• Professional services (architects, attorneys, dentists, physicians, engineers, etc.)
• Radio and television stations
• Telephone exchanges
• Training and skill development not in a school or academic program (this shall include, but not be limited to, tutoring centers, martial arts studios, gymnastics and similar uses regardless of the ages served, and where not classified as a Group A occupancy)