1. U.S. Army Corps of Engineers. (2020). Unified Facilities Criteria (UFC) 4-021-02: Electronic Security Systems.
Page 3-6
Section 3-4.2.2
Infrared Photoelectric Sensors: This section describes photoelectric sensors as "active sensors [that] project a narrow beam of pulsed infrared energy from a transmitter to a receiver." This active projection principle confirms its operational capability in complete darkness.
Page 3-11
Section 3-5.1
Closed Circuit Television (CCTV): This section discusses camera performance relative to light
stating
"The ability of a camera to produce a usable video image is dependent on the amount of light reflected from the scene..." It further details the need for supplemental lighting (visible or IR) for low-light conditions
confirming a standard camera's ineffectiveness in darkness.
Page 3-2
Section 3-2
Intrusion Detection System (IDS) Components: This section distinguishes between sensors (detection)
control units (processing)
and annunciation devices (alarms)
clarifying that an alarm is a separate component from a detector.
2. Garcia
M. L. (2007). The Design and Evaluation of Physical Protection Systems (2nd ed.). Butterworth-Heinemann.
Chapter 5
Intrusion Sensing: This chapter details various sensor technologies. It explains that active infrared sensors (photoelectric beams) are effective because they create their own "monitored energy
" making them independent of environmental lighting. In contrast
it notes that standard CCTV is a passive sensor that relies on available scene illumination.
3. Sennewald
C. A.
& Baillie
C. (2015). Effective Security Management (6th ed.). Butterworth-Heinemann.
Chapter 11
The Alarm System: This chapter explains the fundamental components of an alarm system
consistently identifying three parts: the sensor (detector)
the control panel (circuit)
and the annunciator (alarm/notification). This supports the reasoning that an "alarm" by itself is not a complete or functional security device for detection.