Trane Engineered Smoke Control System, Application Manual

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Associated equipment
BAS-APG001-EN 21
beam, and duct smoke detectors; manual pull stations; and sprinkler flow
devices.
Area smoke detectors
Area smoke detectors detect the presence of smoke at the ceiling. When
activated, an area smoke detector signals the fire alarm system. The
zoning of area smoke detectors must reflect the zoning of the building.
Beam smoke detectors
Beam smoke detectors detect the presence of smoke beneath the ceiling.
When activated, a beam smoke detector signals the fire alarm system. In
atrium applications, beam detectors may replace area smoke detectors.
Beam smoke detectors minimize interference problems created by
stratified hot air under the atrium ceiling.
Duct smoke detectors
Duct smoke detectors detect smoke in building air-distribution system
ductwork. When smoke is present, a signal from the detector deactivates
the fans in the system in which the detector is installed.
However, smoke
control system commands must override fan deactivation by a duct smoke
detector.
In NFPA 90A (NFPA 2002, Standard for the Installation of Air
Conditioning and Ventilating Systems ), section 6.4.2.1 provides the
requirements for duct smoke detectors. Supply duct smoke detectors must
be located downstream of the system filters and ahead of any branch
connection. In mixing systems, this is usually after the return air
connection. Duct smoke detectors may be required in the supply duct of
all air-handling systems greater than 2000 cubic feet per minute (CFM)
and at each floor with a return air volume greater than 15,000 CFM.
Two exceptions limit the use of duct smoke detectors:
• Duct smoke detectors are not required in 100% exhaust air systems.
• Duct smoke detector use is limited if area smoke detectors cover the
entire space served by the return air distribution. Since area smoke
detectors usually cover entire floors, the typical system only requires
one duct smoke detector in the common return duct.
Manual pull stations
Manual pull stations enable occupants to report a fire. When activated, a
manual pull station signals the fire alarm system. A manual pull station
alarm must not initiate the automatic operation of the smoke control
Note:
Fire alarm system equipment is neither furnished nor installed
by Trane.
Note:
Under certain conditions, heat detectors or heat with rate of
rise detectors are preferable to area smoke detectors.