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MAP-21 - Moving Ahead for Progress in the 21st Century

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Guidance on State Safety Data Systems

12/27/2012

Purpose

This guidance clarifies (1) State safety data capabilities to satisfy the "Moving Ahead for Progress in the 21st Century Act" (MAP-21) (P.L. 112-141), and (2) the safety data collection, integration, improvement, and analysis activities eligible for HSIP funding. This guidance supersedes the Guidance Memorandum on Fundamental Roadway and Traffic Data Elements to Improve the Highway Safety Improvement Program, dated August 1, 2011, from the Federal Highway Administration (FHWA), Office of Safety.

Background

The Highway Safety Improvement Program (HSIP) is a core Federal-aid program whose purpose is to achieve a significant reduction in fatalities and serious injuries on all public roads, including non-State-owned public roads and roads on tribal land. [23 U.S.C. 148 (b)(2)]. The HSIP focuses on performance and employs a data-driven, strategic approach to improving highway safety on all public roads.

MAP-21 calls for advancing the capabilities of States for safety data collection, integration, and analysis to support program planning and performance management and continues to support data improvement activities as an eligible HSIP expense. [23 U.S.C. 148 (a)(4)(B)(xiv)]. MAP-21 acknowledges the importance of using multiple data sources to understand highway safety problems and to make effective decisions regarding resource allocation for highway safety. [23 U.S.C. 148 (c)(2)(A)]. To do this, State safety data systems should be sufficient to guide the HSIP and Strategic Highway Safety Plan (SHSP) processes, including analyses and evaluations identified in 23 U.S.C. 148 and 23 CFR Part 924.

MAP-21 State Safety Data System Capabilities

MAP-21 requires that as part of its State highway safety improvement program, a State have in place a safety data system that can be used to perform analyses supporting the strategic and performance-based goals in the SHSP and HSIP. [23 U.S.C. 148 (c)(2)]. This section provides guidance on the capabilities a State's safety data system should have in order to support analyses and evaluations in 23 U.S.C. 148, including: (1) types of roadways covered, (2) types of data included, (3) geolocation of safety data to a common highway basemap, (4) analysis and evaluation capabilities, and (5) the subset of Model Inventory of Roadway Elements (MIRE) to be collected.

Types of Roadways

Consistent with the purpose and scope of the Highway Safety Improvement Program, MAP-21 requires that a State have in place a safety data system to perform safety problem identification and countermeasure analysis. [23 U.S.C. 148 (c)(2)(A)]. The statute also specifies that a State shall advance the capabilities of the State for data collection, analysis, and integration in a manner that includes all public roads, including non-State-owned public roads and roads on tribal land in the State. [23 U.S.C. 148 (c)(2)(D) and (D)(ii)]. Public road means "any road under the jurisdiction of and maintained by a public authority and open to public travel." [23 CFR 460.2(a)].

Types of Data

Safety data means crash, roadway, and traffic data on a public road, and, includes, in the case of a railway-highway grade crossing, the characteristics of highway and train traffic, licensing, and vehicle data. [23 U.S.C. 148 (a)(9)]. Data on train traffic are available through the Federal Railroad Administration crossing inventory (http://safetydata.fra.dot.gov/OfficeofSafety/publicsite/DownloadFStructure.aspx).

MAP-21 requires States to use their safety data systems to identify hazardous locations, sections, and elements that are a danger to all road users, including vehicle occupants and non-occupant users of the roadway (e.g., pedestrians and bicyclists), and to identify fatalities and serious injuries on all public roads by location. [23 U.S.C. 148 (c)(2)(B)(i) and(iii)].

A State's crash, roadway, traffic, licensing, and vehicle data must be able to be linked or combined by virtue of having common data elements. [23 U.S.C. 148 (c)(2)(A)(iii)]. These data should also be able to be linked to a State's other core safety databases including citation or adjudication, and emergency medical services or injury surveillance system. [23 U.S.C. 405 (c)(1)(C) and (c)(3)(C)]. Additionally, commercial motor vehicle data could also be linked based upon involvement in crashes and inspections. A State shall also improve the compatibility and interoperability of safety data with other State transportation-related data systems and with other States and national data systems, e.g., Fatality Analysis Reporting System. [23 U.S.C. 148 (c)(2)(A)(iv)].

Geolocation of Safety Data to a Common Highway Basemap

Crash, roadway, and traffic data should be linkable by geolocation, i.e., a unique location identifier, on a highway basemap, which is defined as "a representation of all public roads that can be used to geolocate attribute data on a roadway." [23 U.S.C. 148 (a)(2)]. States should put in place methodologies to assure that the location of crashes, roadway elements, and traffic data are consistent with the most current basemap. These linkages will support the analysis and evaluation capabilities described below.

The FHWA Office of Highway Policy Information and Office of Planning, Environment, and Realty issued the Memorandum on Geospatial Network for All Public Roads on August 7, 2012. This Memorandum identified a Highway Performance Monitoring System (HPMS) requirement for States to update their Linear Referencing System to include all public roadways within the State by June 15, 2014, in accordance with the HPMS information collection approval from the Office of Management and Budget (2125-0028). This Linear Referencing System is a means to geolocate all safety data on a common highway basemap that includes all public roads.

States that already have basemaps inclusive of all public roads should geolocate all crashes on the basemap and give priority to fatal and serious injury crashes. States without basemaps inclusive of all public roads should first complete the mapping of all roads to the basemap and, once completed at a minimum, geolocate all reportable crashes on the basemap, giving priority to fatal and serious injury crashes.

Analysis and Evaluation Capabilities

Section 148(c)(2) specifies the problem identification and data analysis requirements a State must include as part of its highway safety improvement program. These requirements relate to:

  1. Having in place a safety data system with the ability to perform safety problem identification and countermeasures analysis necessary to accomplish the requirements specified in 23 U.S.C. 148(c)(2)(A).

  2. Based on that analysis, identifying hazardous locations that constitute a danger to motorists (including motorcyclists), bicyclists, pedestrians, and other highway users; establishing the relative severity of those locations; identifying the number of fatalities and serious injuries by location in the State; identifying HSIP projects on the basis of crash data or other data-supported means; and considering which projects maximize opportunities to advance safety. [23 U.S.C. 148(c)(2)(B)].

  3. Adopting strategic and performance based goals considering the impacts to all road users that: address traffic safety that include behavioral and infrastructure problems; focus resources on areas of greatest need; and are coordinated with other State highway safety programs. [23 U.S.C. 148(c)(2)(C)].

  4. Advancing the State's capabilities for safety data collection, analysis, and integration as required under 148(c)(2)(D).

  5. Determining priorities for the correction of hazardous locations, including railway-highway crossings; identifying opportunities for preventing the development of hazardous conditions; and establishing and implementing a schedule for HSIP projects for hazard correction and prevention. [23 U.S.C. 148(c)(2)(E)].

  6. Establishing an evaluation process to analyze and assess results achieved by implemented HSIP projects and use that information in setting priorities for future HSIP projects. [23 U.S.C. 148(c)(2)(F)].

For a list of all the requirements, see 23 U.S.C. 148(c)(2).

Subset of Model Inventory of Roadway Elements (MIRE) to be Collected

The FHWA developed the MIRE, a recommended listing of roadway and traffic elements critical to safety management, as a guide to help transportation agencies improve their roadway and traffic data inventories. MIRE was developed to enhance a State's ability to use advanced safety analyses such as presented in the Highway Safety Manual.

Recognizing the cost and resource commitment to collect all MIRE elements on all public roadways, the FHWA Office of Safety issued the August 1, 2011, Guidance Memorandum on Fundamental Data Elements (FDEs) to Improve the Highway Safety Improvement Program (HSIP), http://safety.fhwa.dot.gov/tools/data_tools/memohsip072911/memohsip072911.pdf. The August 1, 2011 Guidance Memorandum identified 38 elements, divided into the categories of roadway segments, intersections and interchanges. The collection of the FDEs, when integrated with crash data, enables States to conduct a sufficient safety analysis to identify safety problems and make more effective investment decisions. Specifically, the FDEs enable jurisdictions to analyze crash experience on their roadway network relative to the expected average crash frequency given the roadway and traffic characteristics at each location. The August 1, 2011 Guidance Memorandum recommended that these FDEs, in absence of collection of the complete set of MIRE data elements, should be collected on all public roads, as feasible.

MAP-21 requires the Secretary to establish a subset of the MIRE that are useful for the inventory of roadway safety and ensure that States adopt and use the subset to improve data collection. [23 U.S.C. (f)(2)]. FHWA plans to propose new elements as well as requirements for their adoption and use in a forthcoming rulemaking. In the interim, this guidance supersedes the August 1, 2011 memorandum and amends the subset of MIRE elements that States should collect. The revised FDEs include modifications to improve consistency with MIRE Version 1.0. The FDEs are also divided into a full set of FDEs and a reduced set of FDEs for low-volume public roads.

States should incorporate an implementation plan for collecting MIRE FDEs into their next State Traffic Records Strategic Plan update, which is due July 1 of each year under 23 USC 405 (c)(3)(C). States should collect the FDEs on all public roads as soon as practicable in order to benefit from improved analyses as soon as possible.

For Public Roads with AADT > 400 Vehicles per Day

States should collect, at a minimum, the full set of FDEs listed in Table 1 on public roads with an annual average daily traffic (AADT) greater than or equal to 400 vehicles per day. These FDEs provide information on roadway segments, intersections, and ramps and are based upon data needed to conduct a sufficient review of a highway network using existing safety analysis methods. It should be noted that additional data would be needed to diagnose conditions at individual sites, to select countermeasures, and to prioritize projects. States should consider all roadway and traffic elements needed to satisfy the full range of safety analyses they perform.

For Public Roads with AADT < 400 Vehicles per Day

For public roads with an AADT less than 400 vehicles per day, States may use a reduced set of FDEs, because public roads with these traffic volumes routinely have no more than two through lanes and partial or no access control. This reduced set of FDEs is divided into categories of roadway segment elements and intersection elements. States should collect, at a minimum, the reduced set of FDEs listed in Table 2 on public roads with an AADT less than 400 vehicles per day.

Safety Data Activities Eligible for HSIP Funding

States rely on the collection and analysis of safety data to conduct problem identification, countermeasure identification, and project prioritization, which are the foundation of the HSIP process. States also use safety data to evaluate the effectiveness of their program of implemented safety projects. In general, HSIP funds may be used to conduct these functions. [23 U.S.C. 148 (a)(4)(B)(xiv)]. Additionally, States' efforts to improve, update or enhance their ability to collect and analyze data in support of these HSIP functions are eligible activities.

Eligible Safety Data Collection, Analysis, and Improvement Activities

The term "highway safety improvement projects," is broadly defined in 23 U.S.C. 148(a)(4) as "strategies, activities, and projects on a public road that are consistent with a State's SHSP, and correct or improve a hazardous road location or feature or address a highway safety problem." Collection, analysis and improvement of safety data is specifically identified as an eligible project within the definition of a highway safety improvement program under 23 USC 148(a)(4)(B)(xiv). The term "data improvement activities" means "a project or activity to further the capacity of a State to make more informed and effective safety infrastructure investment decisions. [23 U.S.C. 148 (f)(1)(A)]. Safety data collection, analysis, and improvement activities are woven throughout section 148, and examples of such eligible activities include:

  1. Collecting, maintaining, and sharing safety data on all public roads and related systems associated with analytical usage of the data that directly supports HSIP implementation efforts. 23 USC 148(f)(1)(B)(vi).
  2. This includes the collection of MIRE or other data for creation of or use on a highway basemap of all public roads. 23 U.S.C. 148(f)(1)(B)(ii).
  3. Improving the State's ability to identify the number of fatalities and serious injuries on all public roadways in the State with a breakdown by functional classification and ownership in the State. 23 U.S.C. 148(c)(2)(D)(v).
  4. Improving data timeliness, accuracy, completeness, uniformity, integration, and accessibility. 23 U.S.C. 148(c)(2)(A)(i).
  5. Evaluating the effectiveness of safety data system improvement efforts. 23 U.S.C. 148(c)(2)(a)(ii).
  6. Evaluating the effectiveness of highway safety improvement projects. 23 U.S.C. 148(c)(2)(F)(i).
  7. Improving the ability to link State safety data systems with other data systems within the State. 23 U.S.C. 148(c)(2)(A)(iii).
  8. Improving the compatibility and interoperability of safety data with other State transportation-related data systems and the compatibility and interoperability of State safety data systems with data systems of other States and national data systems. 23 U.S.C. 148(c)(2)(A)(iv).
  9. Improving the ability to collect data on non-motorized (e.g., pedestrian and bicyclist) crashes. 23 U.S.C. 148(c)(2)(A)(vi).
  10. Creating, updating, or enhancing a highway basemap of all public roads in a State. 23 U.S.C. 148(f)(1)(B)(i).
  11. Storing and maintaining safety data in an electronic manner. 23 U.S.C. 148(f)(1)(B)(iii).
  12. Developing analytical processes for safety data elements. 23 U.S.C. 148(f)(1(B)(iv).
  13. Acquiring and implementing roadway safety analysis tools. 23 U.S.C. 148(f)(1)(B)(v).

Complementary Processes

MAP-21 requires that a State's efforts to advance its capabilities for safety data collection, analysis, and integration be conducted in a manner that complements the National Highway Traffic Safety Administration's Highway Safety Program (HSP) under 23 U.S.C. 402, and the Federal Motor Carrier Safety Administration's Commercial Vehicle Safety Plan (CVSP) under 49 U.S.C. 31102. [23 U.S.C. 148 (c)(2)(D)(i)]. The State's Traffic Records Coordinating Committee (TRCC) would be an appropriate body through which the safety data programs for the HSIP, the HSP and the CVSP may be reviewed, considered and developed into complementary data programs. These programs' projects should be identified and included in the State's Traffic Records Strategic Plan.

Table 1 - MIRE Fundamental Data Elements for Roads with AADT > 400 Vehicles per Day

MIRE Name (MIRE Number)^
Roadway Segment Intersection
Segment Identifier (12) Unique Junction Identifier (120)
Route Number (8)* Location Identifier for Road 1 Crossing Point (122)
Route/street Name (9)* Location Identifier for Road 2 Crossing Point (123)
Federal Aid/ Route Type (21)* Intersection/Junction Geometry (126)
Rural/Urban Designation (20)* Intersection/Junction Traffic Control (131)
Surface Type (23)* AADT (79) [for Each Intersecting Road]
Begin Point Segment Descriptor (10)* AADT Year (80) [for Each Intersecting Road]
End Point Segment Descriptor (11)*  
Segment Length (13)*  
Direction of Inventory (18) Unique Approach Identifier (139)
Functional Class (19)*  
Median Type (54)  
Access Control (22)*  
One/Two-Way Operations (91)* Interchange/Ramp
Number of Through Lanes (31)* Unique Interchange Identifier (178)
Average Annual Daily Traffic (79)* Location Identifier for Roadway at Beginning Ramp Terminal (197)
AADT Year (80)* Location Identifier for Roadway at Ending Ramp Terminal (201)
Type of Governmental Ownership (4)* Ramp Length (187)
  Roadway Type at Beginning Ramp Terminal (195)
  Roadway Type at Ending Ramp Terminal (199)
  Interchange Type (182)
  Ramp AADT (191)*
  Year of Ramp AADT (192)*
  Functional Class (19)*
  Type of Governmental Ownership (4)*

^Model Inventory of Roadway Elements-MIRE, Version 1.0, Report No. FHWA-SA-10-018, October 2010, http://safety.fhwa.dot.gov/tools/data_tools/mirereport/index.cfm.

*Highway Performance Monitoring System full extent elements are required on all Federal-aid highways and ramps located within grade-separated interchanges, i.e., National Highway System (NHS) and all functional systems excluding rural minor collectors and locals.

Table 2- MIRE Fundamental Data Elements for Roads with AADT < 400 Vehicles per Day

MIRE Name (MIRE Number)^
Roadway Segment Intersection
Segment Identifier (12) Unique Junction Identifier (120)
Functional Class (19)* Intersection/Junction Geometry (126)
Surface Type (23)* Location Identifier for Road 1 Crossing Point (122)
Type of Governmental Ownership (4)* Location Identifier for Road 2 Crossing Point (123)
Number of Through Lanes (31)* Intersection/Junction Traffic Control (131)
Average Annual Daily Traffic (79)*  
Begin Point Segment Descriptor (10)*  
End Point Segment Descriptor (11)*  
Rural/Urban Designation (20)*  

^Model Inventory of Roadway Elements-MIRE, Version 1.0, Report No. FHWA-SA-10-018, October 2010, http://safety.fhwa.dot.gov/tools/data_tools/mirereport/index.cfm.

*Highway Performance Monitoring System full extent elements are required on all Federal-aid highways and ramps located within grade-separated interchanges, i.e., National Highway System (NHS) and all functional systems excluding rural minor collectors and locals.

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