Interpretation #7153

Published April 04, 2013

Original Request

Code Version: 2010
Code: MECHANIC
Code Description: Mechanical
Chapter: 5
Section: 504.8
Topic: standby generator

Question

Is it the intent of 504.8 to require a standby generator to power dryer exhaust fans that serve multi-sory common dyer exhaust systems in non- high rise residential buildings?

Answer Published 04/04/2013 at 3:17 PM

Yes. The Florida Mechanical Code 2010 Sec. 504.8- item 7
clearly requires stand by power.

Commentary

The purpose is to restict such systems from being able to act as a chimney stack and allow smoke to get into multiple other units. Dryer vents are not permitted to have fire or smoke dampers installed in the ducts. Therefore, if a multi- story or common venting system is utilized, considerations have to be made in the gauge of the metal used for venting and maintaining a negative pressure on the system in the event a fire happens in the venting system or building. Chapter 6 has specific exceptions to bathroom and dryer exhaust in a rated shaft for B and R occupancies.