skip navigation


Register for Latest Research

Stay Informed
Register with NCJRS to receive NCJRS's biweekly e-newsletter JUSTINFO and additional periodic emails from NCJRS and the NCJRS federal sponsors that highlight the latest research published or sponsored by the Office of Justice Programs.

NCJRS Abstract

The document referenced below is part of the NCJRS Virtual Library collection. To conduct further searches of the collection, visit the Virtual Library. See the Obtain Documents page for direction on how to access resources online, via mail, through interlibrary loans, or in a local library.


NCJ Number: 76462 Find in a Library
Title: Effective Use of Intrusion Alarms (From Clandestine Tactics and Technology - A Technical and Background Intelligence Data Service, Volume 5 See NCJ-77151)
Author(s): J M Montgomery
Date Published: 1979
Page Count: 24
Sponsoring Agency: International Assoc of Chiefs of Police
Alexandria, VA 22314
Sale Source: International Assoc of Chiefs of Police
44 Canal Center Plaza, Suite 200
Alexandria, VA 22314
United States of America
Language: English
Country: United States of America
Annotation: Alarm system characteristics are identified, their components are discussed, and alarm system design considerations for residential and office applications are described.
Abstract: As crime and terrorism continue to grow, the need for alarm systems increases. Both criminal and terrorist acts depend on surprise, and an effective alarm system, therefore, should give an early warning of acts in progress and possibly detect tampering or attempted entry. Purely destructive acts (sabotage or assassination) are most difficult to protect against. Alarm systems consist of sensors that monitor the environment, triggering circuits that communicate sensor changes, indicators that translate sensor changes into signals identifiable by humans, a communications link between these components, and a power source. The primary purpose of an alarm system is detection; protection is provided through the combination of the alarm system with a response mechanism. A variety of sensors are available, including point or spot devices, such as switches, pressure sensors, foil or tape, vibration sensors, and wires. Area or volume alarm sensors monitor three-dimensional spaces and large volumes of space. These incude types of sensors such as: ultrasonic, infrared, monostatic microwave, audio, light beam, capacitance proximity, perimeter, bistatic microwave, buried, fence-associated, electric-field or E-field, and closed-circuit television motion detectors. Residential security system considerations include the structuring of communications links through telephones or existing cable television lines for outside response forces. These systems are generally ineffective in detecting terrorist acts due to the length of response time, the nature of communications lines, and the fact that perimeter alarms are most commonly used and are most easily circumvented. Duress alarms which can be manually activated in emergencies should be located in residences vulnerable to terrorist attack. Systems for office environments can provide protection during the day and when the area is unoccupied through the selective use of sensors. Industrial systems should provide perimeter protection as well as indepth protection. The characteristics and installation of a wide variety of sensor types -- including ultrasonic, monostatic microwave, and vibration sensors -- are described and trends in alarm systems are discussed. The characteristics of indicators, power sources, and communications links are also detailed. Illustrations, 23 references, and 25 system criteria references are provided.
Index Term(s): Alarm systems; Business security; Facility security; Industrial security; Intrusion detectors; Residential security
To cite this abstract, use the following link:

*A link to the full-text document is provided whenever possible. For documents not available online, a link to the publisher's website is provided. Tell us how you use the NCJRS Library and Abstracts Database - send us your feedback.