UFC 4-021-02NF
27 September 2006
change 1, 23 October 2006
5-3.2.5
Use volumetric sensors in conjunction with glass break sensors in protected
areas.
5-3.2.6 Use dual-technology glass break sensors (acoustic and shock wave). There
is not a significant price difference between a simple acoustic sensor and a combination
sensors (acoustic and shock). For the nominal component price increase, which is a
fraction of the total installed cost, the increased capability justifies the higher cost.
5-3.2.7 Check glass break sensor specifications to ensure they are rated for the type
of glass used, typically laminated glass.
5-3.3
Motion Activated Cameras. A fixed camera with a video motion feature can
be used as an interior intrusion point sensor. In this application, the camera can be
directed at an entry portal (door) and send an alarm signal when an intruder enters the
field-of-view. This device has the added advantage of providing a video image of the
event. The key to good video motion detection is contrast. Activation of a door will
provide sufficient contrast. An intruder in a white lab coat walking down a corridor with
white walls might not generate sufficient contrast. Application of video motion cameras
as an interior intrusion device requires coordination with the building architect and or
interior designer. Interior video motion cameras can also be alarmed by someone
cutting off the lights. As with any camera, the better the lighting, the better the detection
capability. Use of cameras, requires careful consideration of the background image and
normal or abnormal changes to that background image.
Internal motion-activated cameras act as a detection means for stay-behind covert
intruders.
5-3.4
Other CCTV Detection Methodologies. (Refer to Chapter 4 for subsections
on video content analysis and motion path analysis in the section Employment of CCTV
Cameras for Intrusion Detection.) When these other methodologies are used, consider
the following guidance:
5-3.4.1
Require good lighting.
5-3.4.2 Best done where there is a stable background image and intrusion would
generate sharp image contrast.
5-3.5
Interior Volumetric Sensors. Volumetric sensors monitor an internal area to
detect the presence of an intruder. There are several types of volumetric sensors
dual-technology (microwave and PIR). The most commonly used are dual-technology
sensors.
5-3.6
building spaces. An application is an administrative building that is normally only
password protected building entry control system, which is monitored by an off-site
Central Station. When someone has logged into the building with a proper password,
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