Browse Definitions :
Definition

variable speed limit (VSL)

Contributor(s): Ivy Wigmore

A variable speed limit is a flexible restriction on the rate at which motorists can drive on a given stretch of road. The speed limit changes according to the current environmental and road conditions and is displayed on an electronic traffic sign. Signs typically indicate a maximum speed and may also list the minimum.

Variable speed limits are implemented to increase safety and provide clear guidance for motorists. Conventional speed limit signs, in contrast, usually list a single speed, generally the maximum rate. The maximum speed limit is generally considered to apply when conditions are optimal: There is no precipitation or fog and the roads are free of snow, water and ice, for example. Drivers are expected to adjust their speed to adapt to any adverse conditions, but there are no rates specified for particular situations.

variable-speed-limitThe lack of specificity of conventional signage can contribute to accidents, speeding tickets and criminal charges. Many motorists assume that posted speed limits apply at all times and drive at that speed in all conditions, but the maximum speed can be quite unsafe at other times. Charges for "excessive speed" can be the result, even though the motorist may have been driving under the posted speed limit. In the event of an accident, excessive speed could be considered dangerous driving and result in criminal charges.

Flexible speed limits solve that problem by adapting so that the posted speed limit is appropriate for the current conditions. Currently, the speed limit indicated on a variable sign is usually determined by a centralized authority, as deemed appropriate for conditions. As the Internet of Things (IoT) develops, however, networked sensors in the environment are likely to automate that process; connected and self-driving cars could also be designed to comply automatically.

This was last updated in April 2017

Continue Reading About variable speed limit (VSL)

Start the conversation

Send me notifications when other members comment.

Please create a username to comment.

-ADS BY GOOGLE

File Extensions and File Formats

SearchCompliance

  • compliance audit

    A compliance audit is a comprehensive review of an organization's adherence to regulatory guidelines.

  • regulatory compliance

    Regulatory compliance is an organization's adherence to laws, regulations, guidelines and specifications relevant to its business...

  • Whistleblower Protection Act

    The Whistleblower Protection Act of 1989 is a law that protects federal government employees in the United States from ...

SearchSecurity

  • RSA algorithm (Rivest-Shamir-Adleman)

    The RSA algorithm is the basis of a cryptosystem -- a suite of cryptographic algorithms that are used for specific security ...

  • remote access

    Remote access is the ability to access a computer or a network remotely through a network connection.

  • IP Spoofing

    IP spoofing is the crafting of Internet Protocol (IP) packets with a source IP address that has been modified to impersonate ...

SearchHealthIT

SearchDisasterRecovery

  • network disaster recovery plan

    A network disaster recovery plan is a set of procedures designed to prepare an organization to respond to an interruption of ...

  • virtual disaster recovery

    Virtual disaster recovery is a type of DR that typically involves replication and allows a user to fail over to virtualized ...

  • tabletop exercise (TTX)

    A tabletop exercise (TTX) is a disaster preparedness activity that takes participants through the process of dealing with a ...

SearchStorage

  • enterprise storage

    Enterprise storage is a centralized repository for business information that provides common data management, protection and data...

  • disk array

    A disk array, also called a storage array, is a data storage system used for block-based storage, file-based storage or object ...

  • optical storage

    Optical storage is any storage type in which data is written and read with a laser. Typically, data is written to optical media, ...

Close