Speed related crashes represent both crashes where a vehicle was exceeding the posted speed limit as well as those cases where police reported that a vehicle’s speed was unsafe for road, weather, traffic or other environmental conditions at the time.

The data from 2010-2014 fatal crashes in Tribal areas indicates that just over one-third of the speed related fatalities were due to traveling too fast for conditions. Another one-third of the speed related crashes were due to exceeding the posted speed limit. One in four speed related fatalities involved vehicles racing. The remaining speed involved crashes did not have the specifics reported. (Source: Tribal Transportation Strategic Safety Plan)

 

Resources

FHWA, Determining Appropriate Speed Limits - US LIMITS
Link
NHTSA, Countermeasures that Work: Link
ITE, Traffic Calming Guide Link
FHWA, Speed Management Safety Link