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 Section 6:
REMOTE ALARM ASSESSMENT
6.1 The Role of CCTV in Security Operations. Presently, the primary means
of remote alarm assessment is closed-circuit television (CCTV). (Other
remote assessment means such as audio assessment are in use, but are used
primarily as inherent additional features of particular sensor systems.
These have been briefly addressed in Section 4. They will not be discussed
further in this manual because of their extremely limited use in USN
applications. Other means such as binoculars, night vision devices, etc.
are beyond the scope of this DM.) CCTV's value in increasing the efficiency
and effectiveness of security personnel is well recognized. It has been
proven as a cost-effective alternative to human on-the-spot assessment, and
has a demonstrated return value by facilitating security upgrades without
the normally attendant and expensive manpower authorization increases. This
section will discuss CCTV so that the security system designer will be able
to apply this element of the security system properly to the overall
security system design. The discussions will be limited to black and white
CCTV components since, at the present time, color components have not been
proven cost-effective for most security applications.
6.1.1 Near Real Time Alarm Assessment. This is the most common use of CCTV
and operates on the concept of allowing a remotely located human (guard,
watchstander, etc.) to assess one or several alarmed sensor zone(s) in near
real time. The term "near real time" is used to denote the difference
between the direct visual assessment in "real time" possible when a guard is
stationed directly at an alarming sensor location and the time delay
associated with remote alarm assessment using CCTV. The resultant
difference in time is comprised of the time it takes for the sensor alarm
signal to be processed, for the appropriate CCTV camera to be selected, and
for the resultant scene to be displayed to the remotely located alarm
station monitor. With modern solid state electronics, this time delay
varies from one to a few seconds, depending upon system design. Emerging
technologies, such as digitized video frame storage, will enable a remotely
located alarm station monitor to also view the scene of an alarm sensor zone
at the instant of initial sensor alarm. At the present, to minimize video
data display delay time and thereby minimize the time until viewing of the
alarmed sensor zone scene after the alarm event, two techniques may be used.
The first is to have the entire video system display all sensor zones for
the alarm monitor continuously. This is not recommended because it induces
boredom and fatigue and is expensive due to the number of CCTV monitors
required. The second and preferred technique is to have the system active
continuously, but to display no video data to the alarm monitor until an
alarm event occurs. This eliminates electronic warmup time delay as did the
first technique but also assures that alarmed sensor zones receive immediate
attention when an alarm event occurs. The use of a video switcher with this
second technique reduces the number of monitors required for display of data
for the entire system. (The use of video switchers and operator control
options is covered further in paragraph titled "Options for Enhanced
Capabilities.") Near real time alarm assessment by CCTV facilitates
effective alarm response direction in an economical manner.
13.02-82
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