FHWA Reduced Speed Limit Data Set

Project Description The NDS supplemental speed limit data set was developed to complement the RID reduced speed limit data set by linking SHRP2 NDS vehicle summary measures with the linear referencing system (LRS) routes that exist within the RID. To remain consistent with other SHRP2 NDS data sources, a link and node roadway representation was used for the supplemental speed limit data set. The links layer provided with the RID facilitated the mapping of the LRS road segments to the link road segments format. Data Request Scope Each row of the supplemental speed data set represents a traversal of a link for which a speed limit was identified in the RID reduced speed limit data set and for which vehicle network speed data was collected. For each of these traversals 21 variables were recorded. Two versions of the data set have been created, one that has had PII (in terms of link traversals near the trip origin and destination or crash events) removed and another with PII links included. The non-PII version of the data set consists of approximately 117,000,000 link traversals across the 6 SHPR2 sites. Data Specification Details about data set creation and variables recorded can be found in the accompanying data dictionary.