4
effective range of the 2001-130 siren is
approximately 6400 feet.
Wind speed and direction often affect the
propagation of sound from the siren.
Consequently, the direction of the prevailing
wind may also be a factor to consider when
selecting the installation site(s) of a small,
one or two-siren system. For example, if the
prevailing wind is from the west, it may be
desirable to install the siren toward the
western edge of the area to be covered.
Other
factors
to
consider
before
selecting the installation site include the
availability of electrical power, the ease of
installation and maintenance, the height of
surrounding
obstructions,
and
security
against vandalism.
3-2.
SIREN INSTALLATION.
A. General.
Most siren installations are one of two
types: Pole Mount or Flat Surface Mount.
These two configurations make it possible to
install a siren in almost any situation. If the
installations in this paragraph are not
suitable,
modification
of
one
of
the
configurations may be practical.
A siren is typically installed 40-50 ft. above
the ground. If the installation is located less
than 40 ft. above the ground, the sound
intensity at close range may increase, but at
the same time the effective range of the siren
may be reduced. Conversely, if the siren is
located more than 50 ft. above ground, the
effective range of the siren may increase, but
the sound may skip over areas closer to the
siren. These variables may make it desirable
to test the sound coverage of the siren at
various heights and locations whenever
possible.
B.
Pole Mounting.
A typical siren pole-mounted installation
is shown in
Figure 3-1
. The siren is mounted
on a Southern Yellow Pine, Douglas Fir or
equivalent Class 2 utility pole 40-50 ft. above
the ground. It is attached to the pole by
means of legs, as shown in
Figure 3-2
.
Figure 3-1. Typical Pole-mounted Installation
Summary of Contents for 2001-130
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