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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Acoustical Warning Devices as Emergency Warning Systems, Phase 1

Document Series
Technical Reports
Federal Railroad Administration
Report Number
Subject Emergency Notification Systems, Grade Crossing Technology
Emergency warning, train horn, trespassers, music masking sounds, reaction time, acoustic warning device

This program demonstrated the effectiveness of Acoustical Warning Devices (AWD) as secondary Emergency Warning Signals (EWS). The focus is to warn trespassers of an approaching train, through the development of an emergency warning signals that produce a sense of urgency, are noticeable to trespassers wearing headphones, and uniquely identifiable as train warning signals. Several EWS sounds were developed and evaluated in surveys to assess the participant’s view of the sense of urgency and detectability. Sounds characteristics were identified that enhance detectability.

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Last updated: Tuesday, October 8, 2019