CHARLOTTE FIRE DEPARTMENT
FIRE MARSHAL’SOFFICE
500 DALTON AVE
Charlotte Fire Department | 500 Dalton Avenue | Charlotte, NC 28206
d) Floors and roofs: A/AF = 0.00050 where: A = Total leakage area, square feet (m2).
AF = Unit floor or roof area of barrier, square feet (m2).
Aw = Unit wall area of barrier, square feet (m2).
The leakage area ratios shown do not include openings due to gaps around doors and operable
windows. The total leakage area of the smoke barrier shall be determined in accordance with
Section 909.5.1 and tested in accordance with Section 909.5.2.
7. The primary mechanical means of controlling smoke shall be by pressure differences across
smoke barriers. Maintenance of a tenable environment is not required in the smoke-control zone
of fire origin.
8. Where approved by the fire code official, smoke migration through openings fixed in a
permanently open position, which are located between smoke control zones using the airflow
method, shall be permitted. The design airflow shall be in accordance with this section. Airflow
shall be directed to limit smoke migration from the fire zone. The geometry of openings shall be
considered to prevent flow reversal from turbulent effects. Smoke control systems using the
airflow method shall be designed in accordance with NFPA 92.
9. Where approved by the fire code official, mechanical smoke control for large, enclosed volumes,
such as in atriums or malls, shall be permitted to utilize the exhaust method. Smoke control
systems using the exhaust method shall be designed in accordance with NFPA 92.
10. The design fire shall be based on a rational analysis performed by the registered design
professional and approved by the fire code official. The design fire shall be based on the analysis
in accordance with Section 909.4 through 909.9.4, where applicable.
11. Equipment including, but not limited to, fans, ducts, automatic dampers, and balance dampers
shall be suitable for their intended use, suitable for the probable exposure temperatures that the
rational analysis indicates, and as approved by the fire code official. Refer to NCIFC Sections
909.10.1 through 909.10.5.
12. Smoke control systems shall be provided with standby power in accordance with NCIFC Section
604.
13. Fire detection systems providing control input or output signals to mechanical smoke control
systems or elements thereof shall comply with the requirements of Section 907 and Sections