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NCJRS Abstract

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NCJ Number: 77185 Find in a Library
Title: NIJ (National Institute of Justice) Standard for Emergency Vehicle Sirens
Corporate Author: National Institute of Justice (NIJ)
US Department of Justice
Office of Justice Programs
United States of America
Date Published: 1981
Page Count: 15
Sponsoring Agency: National Institute of Justice (NIJ)
Washington, DC 20531
National Institute of Justice/
Rockville, MD 20849
US Dept of Justice NIJ Pub
Washington, DC 20531
Sale Source: National Institute of Justice/
NCJRS paper reproduction
Box 6000, Dept F
Rockville, MD 20849
United States of America
Document: PDF|PDF
Language: English
Country: United States of America
Annotation: This standard establishes performance requirements and test methods for electronic and electromechanical sirens used on law enforcement vehicles to warn pedestrians and motorists of the passage of an emergency vehicle.
Abstract: The standard establishes two classes of sirens, based upon acoustical output. Class A sirens provide as a minimum an A-weighted on-axis sound level of 120 decibels (dB), and class B sirens provide as a minimum an A-weighted on-axis sound level of 115 dB. Definitions are given for terms used in the standard, including anechoic room, automatic operation, A-weighted sound level, wail, and yelp. Equipment requirements are listed, including general requirements, operating life, acoustical performance, and environmental performance. In addition, test requirements are delineated for such important elements as testing procedures, inspection, wattage test, environmental tests, and postenvironmental tests. The environmental tests encompass those for high and low temperature, dust, moisture, corrosion resistance, and vibration. Tables are provided. Six references and information and diagrams on measurements of the acoustical output of emergency vehicle sirens are appended.
Index Term(s): Emergency vehicle warning systems; Law Enforcement Standards Laboratory; Police equipment
Note: Part of the Technology Assessment Program.
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