Section 907.6.4 of the International Fire Code is hereby amended to read as follows:

907.6.4 Zones. Each floor shall be zoned separately, and a zone shall not exceed 22,500 square feet (2090 m²). The length of any zone shall not exceed 300 feet (91,440 mm) in any direction. Floors shall be further zoned to coincide with any fire walls and/or horizontal exits.

Exceptions:

1. Automatic sprinkler system zones shall not exceed the area permitted by NFPA 13.

2. Fire alarm zones that coincide with fire walls and/or horizontal exits are not required in existing buildings except:

a. When a change of use occurs

b. The exiting or evacuation plan is modified and depends on the use of the fire wall or horizontal exit

c. When fire alarm panels are replaced (ref.: BCC 23.11.907.1(2)