Road Weather Management Program
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Best Practices for Road Weather Management Version 2.0


Applications of Variable Speed Limit Systems to Enhance Safety


Variable Speed Limit (VSL) systems are a type of Intelligent Transportation System that utilize speed detection, weather information, and road surface condition technology to determine safe speeds at which drivers should be traveling given current roadway conditions. This paper presents preliminary findings of a study to identify and characterize the usage of VSL throughout the world. Applications in the Netherlands, Germany, Great Britain, Australia, New Jersey, Washington State, Nevada, Arizona, and New Mexico are included.


7th World Congress on ITS; SAIC and FHWA Office of Safety Research and Developement. For an electronic copy of this resource, please direct your request to

Date: 2000


Zahrean, Robinson, Warren


Weather information
Speed management
Pavement condition
Freeway management
Intelligent Transportation Systems (ITS)

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