NFPA 101

A.1.1 The following is a suggested procedure for determining the Code requirements for a building or structure: (1) Determine the occupancy classification by referring to the occupancy definitions in Chapter 6 and the occupancy Chapters 12 through 42. (See 6.1.14 for buildings withmore than one use.) (2) Determine if the building or structure is new or existing. (See the definitions in Chapter 3.) (3) Determine the occupant load. (See 7.3.1.) (4) Determine the hazard of contents. (See Section 6.2.) (5) Refer to the applicable occupancy chapter of the Code, Chapters 12 through 42.