ASHRAE Journal - October 2014 - 78

TECHNICAL FEATURE

FIGURE 2 Combination fire and smoke damper. (Drawing courtesy of
Ruskin Company.)

FIGURE 3 Containment fire and smoke damper with smoke detector.

the damper or an area smoke detection system
may control the damper's closing (Figure 3). The
wiring for the typical combination damper in a
containment application is shown in Figure 4.
Chapter 7 damper applications-as opposed
to those required by Chapter 9-do not require
position indication switches or override control.
These controls may be voluntarily installed in
order to automatically test or provide local status
light indication.

Dampers Required by IBC Chapter 9
FIGURE 4 Controls and wiring for a combination fire and smoke damper.
Chapter 9 of the IBC, Fire Protection Systems,
regulates installation of engineered smoke control systems (as well as alarms and sprinklers).
To exhaust smoke or prevent the movement of smoke
In particular, smoke control dampers are coninto protected spaces, dampers and fans are employed.
trollable by the firefighters' smoke control station
These are considered active systems. They may be
(FSCS) panel via relays for manual override control.
assisted by passive structural features such as architecPosition indication is also required to show open or
tural reservoirs to direct smoke into an exhaust duct.
closed status. These dampers are often referred to
Some of the occupancies where smoke control systems as "re-openable" since they can be remotely opened
are required are in atria, stairwells, underground build- or closed although they are normally in automatic
ings, and large spaces such as malls and auditoriums.
mode. If the damper is for smoke control only, there
Some local codes also require additional protection in
is typically no high temperature limit. Where a wall
corridors and any exit passages.
in which the damper is installed is also a fire wall,
The dampers employed for smoke control are generthe damper has two sensors referred to by UL as
ally of the same physical construction as those for con"heat responsive devices." Figure 5 shows an example
tainment. Some smoke dampers are aluminum whereas damper with dual sensors; position indication
fire and combination dampers are galvanized or stainswitches are not shown.
less steel to handle the higher temperatures to which
Figure 6 shows a typical arrangement of fire alarm
they may be subjected.
panel, smoke control panel, and firefighters' graphic
It is the control capability of the smoke control system
panel for a damper-all inputs and outputs are not
damper that is the significant difference. The system
shown. Some fire alarm panels have integrated smoke
is more sophisticated and is coordinated with alarms,
control. In any event, one control must coordinate
sprinklers, fans, and doors.
among all related systems. The wiring connections on
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ASHRAE Journal - October 2014

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