Mechanical Technical Advisory Committee

Tampa, Florida

December 4, 2006 

The meeting was convened by Chair Steve Bassett at 10:00 a.m. A quorum of eight voting members was present.

Voting Members Present:

Steve Bassett, Bob Andrews, Jim Cummings, Mike McCombs, Don Pittman, Pete Quintela, Joe Crum and Gary Griffin.

Meeting Activities:

The minutes of the 8/21/06 meeting were approved unanimously.

Reconsideration was made of DEC request DCA06-DEC-182 by Michael Thompson of CHPA Consulting Engineers Incorporated. Chairman Bassett explained that it was returned to the TAC based on further thoughts on code language under consideration and turned the meeting over to Commissioner McCombs so he could participate in the discussion. Proponent clarified that he believed the design proposed meets the intent of the code by making up guestroom/bathroom exhaust by using air from the corridor of the Peabody Hotel addition. The door manufacturer's specifications provided by CHPA clarify that the undercut was sufficient to meet the ventilation criteria required by code.

Bassett made the following additional points:

•  Exception 1 to Section 601.2 of the FBC-Mechanical uses the language “including toilet rooms…” This language is not exclusive; there is no indication that these are the only types of rooms that open directly onto the corridor.

•  Exception 1 to Section 601.2 allows the common design practice of using makeup air from the corridor because positive pressure will be created in the corridor with respect to the adjoining rooms and smoke would not be drawn into the corridor. It is not used as a component of the smoke control system because the design puts outside air into the corridor. Most smoke control systems pressurize the corridor during a fire; therefore no smoke would come out of the room into the corridor.

•  The corridor is an occupiable space in that the code requires a means of egress, light and ventilation and occupants are engaged in the labor of movement.

•  Exception 5 to Section 601.2 of the 2001 FBC-Mechanical allowed transfer of air caused by pressure differentials when door clearances do not exceed those specified for fire doors in NFPA 80. This exception was Florida specific but was inadvertently removed from inclusion in the 2004 FBC-Mechanical during the code update process. The exception is not needed because it is included in NFPA 90A.

Discussion of the matter included the following additional points. The term “directly” in section 403.2.2 was an issue because the bathrooms in the design would not open directly onto the corridor. The code allows bathroom exhaust to be drawn from adjoining rooms. The design in question is intended to use air drawn into the guestroom for both supply air and bathroom exhaust air, which will be continuous. The code does not specifically use the concepts of areas of “dirty air” and “clean air”, but the commentary does; air is prohibited from being drawn from kitchens, bathrooms and smoking rooms in any number of places in the code. The code specifically says that corridors shall not be used as supply air (with exceptions). NFPA 90A allows use of makeup air on an “incidental” basis, which is defined as occurring by chance. If the code was amended, use of the corridor for makeup air could be permitted under specific conditions. Although use of treated supply air from a corridor can be an acceptable design option, negative pressures can result in the guestrooms, drawing in humid outdoor air and causing mold growth conditions in the building cavities. Proponent assured the group that mold growth had been considered in the design process. The code does specifically state that a corridor is never a plenum. Commentator does not believe use of the corridor meets the uses specified for “occupiable” space.

On a motion by Crum with a second by Andrews, the TAC voted to uphold the original recommendations to the Florida Building Commission as follows:

To the question, “Does the referenced code allow the transfer of bathroom exhaust make up air from the corridor to the guest room?” the answer is NO; the TAC voted 4 in favor, 4 opposed .

To the question, “Does the referenced code allow the transfer of bathroom exhaust from the guest room to the bathroom?” the answer is YES; the TAC voted unanimously in favor.

To the question, “Does the referenced code allow the bathroom exhaust to be supplied through the corridor?”, the answer is NO; the TAC voted 4 in favor, 4 opposed.

To the question, “Is the guest room corridor an occupied space?” the answer is NO; the TAC voted 4 in favor, 4 opposed.

Adjournment

The meeting was adjourned at 10:55 a.m..

The Chair recommends removing Peggy Patterson and Phillip Simmons from voting member status (both in the producer category) on grounds on non-attendance at the last two meetings. He further recommends replacing them with Dan Griffith, President of the Florida Refrigeration and Air Conditioning Contractors (FRACCA), and Larry Banks of Del-Air.