Speed Related

The Overview

In this document, speed-related collisions are defined as those in which a contributing factor to the collision was either exceeding the posted speed limit or driving too fast for conditions or when a driver was charged for a speed-related offense. Speed-related actions or violations are the fourth most common contributing factor in fatal and severe injury collisions, following roadway departure, unrestrained motor vehicle occupants, and age-related factors. From 2008 to 2012, speeding-related actions or violations were involved in nearly 40% of fatalities and 34% of severe injuries. This figure has been trending down until 2012 when the number of persons killed in speed-related collisions increased (+50). Effective countermeasures for reducing speed-related collisions include education, enforcement, and engineering strategies.

Speeding-related actions are more often attributed to “Driving Too Fast For Conditions” than “Exceeded the Authorized Speed Limit”. Approximately 75% of the total number of speed-related collisions indicated a contributing factor of driving too fast for conditions, compared to 18% for exceeding the speed limit. The remaining collisions were attributed to a speeding related charge (7%). Driving too fast for conditions is not always tied to road or weather conditions; more often than not, the aforementioned contributing factor is used to describe circumstances in which a driver collided with another vehicle that was stopped or slowing in traffic.


Our Challenge

While the number of speed-related fatal and severe injury collisions decreased in South Carolina from 2008 to 2011, and at a greater percent change than the total number of fatal and severe injury collisions, there was a slight increase in the 2012 data. In 2012, 1,218 fatal and severe injury collisions were attributed to speed-related actions taken by drivers. That figure represents an increase (6.5%) over the previous year, when there were 1,144 speed-related collisions in the state. The overall percent reduction in the number of speed-related fatal and severe injury collisions from 2008 to 2012 was 7.9%.

A review of the 2008-2012 fatal and severe injury speed-related collisions shows these collisions occurring primarily on secondary (40.8%) and primary (39%) roadways, with only a small percentage of collisions occurring on interstates (11.6%).

Almost three-fourths of the total number of drivers involved in speed-related fatal and severe injury collisions were males, while only a quarter were female. Males aged 20-24 represented the age group with the highest number of registered drivers (9.1%) and accounted for the highest number of drivers involved in speed-related collisions (11.3%).

Speed Related:
(Route Category)
View Graph
Speed Related:
(Collisions by Driver Age and Gender)
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OUR STRATEGIES

Education, Enforcement, Engineering and Emergency Management Services

1 Reduce speeding through enforcement activities.

Strategies (how)

1.1   Conduct high-visibility enforcement efforts at locations where speeding-related crashes are more prevalent.

Implementation Area(s):  Engineering



1.2   Ensure that law enforcement officers have appropriate equipment for speeding enforcement.

Implementation Area(s):  Engineering



1.3   Research the benefits and challenges of automated speed enforcement; present findings to leadership for their consideration.

Implementation Area(s):  Enforcement,  Legislative,  Engineering



2 Use engineering measures to effectively manage speed.

Strategies (how)

2.1   Set speed limits which account for roadway design, traffic, and environment, including traffic volume, modal mixed-use, and local and regional function.

Implementation Area(s):  Engineering



2.2  Use traffic-calming and other design factors to influence driver speed.

Implementation Area(s):  Engineering



2.3  Design and maintain speed limit signs and ensure that warning signs are visible and installed at appropriate intervals.

Implementation Area(s):  Engineering



2.4  Implement timed and coordinated traffic signals to improve traffic flow, reduce red-light running, and manage speeds.

Implementation Area(s):  Engineering



2.5  Set consistent speed limits based on existing operation, considering road design, traffic flows, traffic mix, and other environmental factors.

Implementation Area(s):  Engineering



3 Increase public awareness of risk of driving at unsafe speeds.

Strategies (how)

3.1   Develop public education materials communicating specific concerns related to speeding.

Implementation Area(s):  Education



3.2  Develop public education campaign designed to widely distribute information related to the dangers of speeding.

Implementation Area(s):  Education



4 Build partnerships to increase support for speed-reducing measures.

Strategies (how)

4.1   Expand corridor safety model to high-crash locations where data suggests a high rate of speeding-related fatal or severe injury crashes.

Implementation Area(s):  Leadership,  Education,  Engineering,  Enforcement