TFHRC Home > Safety > Safety Publications > FHWA-HRT-07-046 > Appendix C

APPENDIX C. PROPOSED MMIRE ELEMENT CODING

The following describes the proposed MMIRE elements. In each case, the element name is in bold, followed by a brief definition of the element, the attributes (proposed coding), and the source of coding. The latter will be one or more of the four primary data sources or the project team. The elements are numbered for cross-referencing with the same element in the Appendix B matrix.

I. ROADWAY SEGMENT DESCRIPTORS

I.A. SEGMENT LOCATION/LINKAGE VARIABLES

(Note that whatever linear reference or spatial variables are used, they must be consistent across all safety data files.)

1. COUNTY
Definition: County location of segment
Attributes:

• Record the county name or equivalent entity. If codes are used instead of name, use the GSA Geographic Locator Codes (GLC) that can be found on the Internet at: http: //www.gsa.gov/Portal/gsa/ep/contentView.do?contentType=GSA_OVERVIEW&contentId=8815&noc=T. If State-assigned codes are used, they should be convertible to the GSA/FIPS format.

Source of Coding: Project Team

2. CITY/LOCAL JURISDICTION
Definition: City/local jurisdiction location of segment if applicable
Attributes:

• Record the city name or equivalent entity. If codes are used instead of name, use the GSA Geographic Locator Codes (GLC) that can be found on the Internet at: http: //www.gsa.gov/Portal/gsa/ep/contentView.do?contentType=GSA_OVERVIEW&contentId=8815&noc=T. If State-assigned codes are used, they should be convertible to the GSA/FIPS format.

Source of Coding: Project Team3. ROUTE NUMBER
Definition: Route number
Attributes:

• 20-character alphanumeric value

Source of Coding: SafetyAnalyst

4. STREET NAME
Definition: Street name
Attributes:

• Alpanumeric Street Name

Source of Coding: All sources 5. SECTION END-POINTS DESCRIPTORS
Definition: Location information defining the location on a route of each endpoint of the section
Attributes:

• Section end-point descriptors can be either related to a Linear Reference System (e.g.,Route-beginning milepoint, Route-ending milepoint) or to a spatial data system (i.e.,longitude/latitude for begin and end points). The descriptor-types used must be common across all MMIRE files and compatible with crash data location coding.

Source of Coding: All sources 6. SECTION IDENTIFIER
Definition: Unique segment identifier, derived from other variables (e.g., combination of route number, county location and beginning and ending mileposts)
Attributes:

• See definition

Source of Coding: All sources

7. SECTION LENGTH
Definition: Section length
Attributes:

• Section length in miles or kilometers

Source of Coding: All sources 8. HIGHWAY DISTRICT
Definition: Highway district
Attributes:

• Numeric district number
• Not applicable
• Unknown

Source of Coding: SafetyAnalyst

9. GOVERNMENTAL OWNERSHIP
Definition: Governmental owner of segment (including FIPS code)
Attributes:

• Record the city name or equivalent entity. If codes are used instead of name, use the GSA Geographic Locator Codes (GLC) that can be found on the Internet at: http: //www.gsa.gov/Portal/gsa/ep/contentView.do?contentType=GSA_OVERVIEW&contentId=8815&noc=T. If State-assigned codes are used, they should be convertible to the GSA/FIPS format.

Source of Coding: Project Team

10. TYPE OF GOVERNMENTAL OWNERSHIP
Definition: Type of governmental ownership
Attributes:

• State
• County
• Town/township
• Municipal
• Other State agency
• Other local agency
• Federal agency
• Other

Source of Coding: HPMS

11. ROUTE SIGNING
Definition: Type of route signing on the segment
Attributes:

• Interstate
• U.S
• State
• Off-interstate business marker
• County
• Township
• Municipal
• Parkway or forest route
• Other
• Not signed

Source of Coding: HPMS

12. ROUTE SIGNING QUALIFIER
Definition: Whether the route is "business" or other qualifier
Attributes:

• Unqualified
• Alternate
• Business route
• Bypass
• Spur
• Loop
• Proposed
• Temporary
• Truck route
• None of the above

Source of Coding: HPMS

13. COINCIDING ROUTE INDICATOR
Definition: Whether the route segment is a "primary" coinciding route (i.e., the route that crashes are referenced to) or a "minor" coinciding route
Attributes:

• Numeric code indicating "primary" (crash-linked) route or "minor" route

Source of Coding: Project Team

14. COINCIDING-ROUTE PRIMARY ROUTE NUMBER
Definition: If a minor conciding route segment, the route number for the major (primary) route
Attributes:

• 20-character alphanumeric value

Source of Coding: SafetyAnalyst

15. DIRECTION OF INVENTORY
Definition: Direction of Inventory
Attributes:

• Compass direction if divided roads are inventoried in each direction due to different characteristics on each roadway; "both" if inventory in only one direction

Source of Coding: Project Team

I.B. SEGMENT ROADWAY CLASSIFICATION

16. FUNCTIONAL CLASS
Definition: Functional class
Attributes:

• Principal arterial interstate
• Principal arterial other freeways and expressways
• Principal arterial other
• Minor arterial
• Major collector
• Minor collector
• Local

Source of Coding: HPMS, IHSDM

17. RURAL/URBAN DESIGNATION
Definition: Rural/urban designation
Attributes:

• Rural
• Urban
• Not applicable
• Unknown

Source of Coding: SafetyAnalyst

18. FEDERAL AID/ ROUTE TYPE
Definition: Federal aid/route type
Attributes:

• Route is on NHS
• Route is an NHS connector
• Route is unrelated to NHS

Source of Coding: HPMS

19. ACCESS CONTROL
Definition: Access control
Attributes:

• Full
• Partial
• None

Source of Coding: All sources

20. OPERATIONAL CLASS
Definition: Operational class of segment if different from offical functional class
Attributes:

• Principal arterial interstate
• Principal arterial other freeways and expressways
• Principal arterial other
• Minor arterial
• Major collector
• Minor collector
• Local

Source of Coding: HPMS, IHSDM

I.C. SEGMENT CROSS SECTION

I.C.1. SURFACE DESCRIPTORS

21. SURFACE TYPE
Definition: Surface type
Attributes:

• Concrete
• Asphalt
• Gravel
• Dirt

Source of Coding: SafetyAnalyst

22. SURFACE FRICTION
Definition: Surface friction indicator
Attributes:

• Measured skid number on the segment or general indication of wet-surface friction (e.g.,high, medium, low)

Source of Coding: Project Team

23. SURFACE FRICTION DATE
Definition: Date surface friction was measured or assigned
Attributes:

• mm/dd/yyyy

Source of Coding: Project Team

24. TOTAL SURFACE WIDTH
Definition: Total paved surface width (could be derived if all other lane widths are captured)
Attributes:

• Feet or meters

Source of Coding: All sources

25. PAVEMENT ROUGHNESS/CONDITION
Definition: Pavement roughness (roughness number)
Attributes:

• International Roughness Index (IRI)

Source of Coding: HPMS

26. PAVEMENT ROUGHNESS DATE
Definition: Date pavement roughness was assigned
Attributes:

• mm/dd/yyyy

Source of Coding: Project Team

27. PAVEMENT CONDITION
Definition: Pavement condition (descriptive scale)
Attributes:

• Numeric rating 1.0–5.0 if IRI not provided

Source of Coding: HPMS

28. PAVEMENT CONDITION DATE
Definition: Date pavement condition was assigned
Attributes:

• mm/dd/yyyy

Source of Coding: Project Team

I.C.2. LANE DESCRIPTORS

29. NO. OF THRU LANES
Definition: Number of thru lanes, including HOV and reversible lanes
Attributes:

• Numeric

Source of Coding: All sources

30. AVERAGE THRU LANE WIDTH
Definition: Average lane width used by traffic (i.e., not including wide curb lanes, parking area, bicycle lanes, etc.)
Attributes:

• Feet or meters

Source of Coding: All sources

31. EXCLUSIVE LEFT TURN LANE PRESENCE
Definition: Exclusive left turn lane presence and number for both divided and undivided roadways. Supplemental information on left turn lane type in medians of divided roadways (e.g.,directional left turn lane) is captured under Median Descriptors
Attributes:

• None
• Single LT lane
• Multiple LT lane

Source of Coding: Project Team

32. EXCLUSIVE LEFT TURN LANE LENGTH
Definition: Exclusive left turn lane length
Attributes:

• Full segment length
• Length in feet or meters if not full segment length

Source of Coding: Project Team

33. EXCLUSIVE RIGHT TURN LANE PRESENCE
Definition: Exclusive right turn lane presence and number
Attributes:

• None
• Single RT lane
• Multiple RT lanes

Source of Coding: Project Team

34. EXCLUSIVE RIGHT TURN LANE LENGTH
Definition: Exclusive right turn lane length
Attributes:

• Full segment length, or length in feet or meters if not full segment length

Source of Coding: Project Team

35. AUXILIARY LANE PRESENCE/TYPE
Definition: Presence or type of auxiliary lane
Attributes:

• Climbing lane
• Passing lane
• Acceleration lane
• Deceleration lane
• Other

Source of Coding: Project Team

36. AUXILIARY LANE LENGTH
Definition:
Attributes:

• Full segment length, length in feet or meters if not full segment length

Source of Coding: Project Team

37. HOV LANES
Definition: Presence of HOV lanes in segment
Attributes:

• None
• Increasing direction
• Decreasing direction
• Both directions

Source of Coding: Project Team

38. HOV LANE TYPES
Definition: HOV lane types
Attributes:

• No HOV lanes
• Has exclusive HOV lanes
• Normal thru lanes used as HOV at specified times
• Shoulder/parking lanes used as HOV at specified times

Source of Coding: HPMS

39. REVERSIBLE LANES
Definition: Number of reversible lanes present on segment
Attributes:

• No reversible lanes
• One reversible lane
• Two reversible lanes
• More than two reversible lanes

Source of Coding: Project Team

40. PRESENCE/TYPE OF BICYCLE FACILITY
Definition: Presence or type of bicycle facility on segment
Attributes:

• None
• Wide curb lane
• Marked bike lane
• Separate parallel bike path
• Signed bike route only
• Other

Source of Coding: Project Team, SafetyAnalyst

41. WIDTH OF MARKED BICYCLE LANE OR BIKE PATH
Definition: Width of marked bicycle lane or bike path
Attributes:

• Feet or meters

Source of Coding: Project Team

42. WIDTH OF WIDE CURB LANE
Definition: Width of wide curb lane used by both vehicles and bicycles
Attributes:

• Feet or meters

Source of Coding: Project Team

43. NUMBER OF PEAK HOUR LANES
Definition: Number of through lanes used in peak period in the peak direction, Include HOV lanes, reversible lanes, parking lanes, or shoulders that legally are used for through traffic during the peak period in the peak direction.
Attributes:

• Numeric

Source of Coding: HPMS

I.C.3. SHOULDER DESCRIPTORS

44. RIGHT SHOULDER TYPE
Definition: Shoulder type on right side of road in direction of inventory
Attributes:

• Paved
• Composite
• Gravel
• Turf
• Curb with no shoulder in front of it
• No shoulder
• Not applicable
• Unknown

Source of Coding: SafetyAnalyst

45. RIGHT SHOULDER TOTAL WIDTH
Definition: Total width of right shoulder including paved and unpaved parts
Attributes:

• Feet or meters

Source of Coding: All sources

46. RIGHT PAVED SHOULDER WIDTH
Definition: Width of paved portion of right shoulder
Attributes:

• Feet or meters

Source of Coding: All sources

47. LEFT SHOULDER TYPE
Definition: Shoulder type on left side of roadway in direction of inventory. For undivided roads and divided roads with one direction of inventory, this will be the outside shoulder on the opposing side. Note that information on paved width of the inner (left) shoulder is included under median descriptors.

Attributes:

• Paved
• Composite
• Gravel
• Turf
• Curb with no shoulder in front of it
• No shoulder
• Not applicable
• Unknown

Source of Coding: SafetyAnalyst

48. LEFT SHOULDER TOTAL WIDTH
Definition: Width of left (outside) shoulder, including paved and unpaved parts. See definition of "Left Shoudler Type" above.
Attributes:

• Feet or meters

Source of Coding: All sources

49. LEFT PAVED SHOULDER WIDTH
Definition: Width of paved portion of left shoulder. See definition of "Left Shoudler Type" above.
Attributes:

• Feet or meters

Source of Coding: All sources

50. SHOULDER RUMBLE STRIP PRESENCE
Definition: Presence of shoulder rumble strip
Attributes:

• On both shoulders of roadway segment
• Right shoulder only
• Left shoulder only
• No shoulder rumble strip

Source of Coding: Project Team

51. RUMBLE STRIP TYPE
Definition: Rumble strip type if present
Attributes:

• Milled
• Rolled
• Milled or rolled on edgeline
• Raised on edgeline

Source of Coding: Project Team

52. SIDEWALK PRESENCE
Definition: Presence of sidewalk in direction of inventory
Attributes:

• None
• Left side
• Right side
• Both sides

Source of Coding: Project Team

53. CURB PRESENCE
Definition: Presence of curb
Attributes:

• No curb
• Curb on left
• Curb on right
• Both curbs

Source of Coding: TSIMS

54. CURB TYPE
Definition: Curb type
Attributes:

• No curb
• Straight-face curb (i.e., "barrier curb")
• Slope-face curb

Source of Coding: Project Team

I.C.4. MEDIAN DESCRIPTORS

55. MEDIAN TYPE
Definition: Median type
Attributes:

• Undivided
• Flush paved median [at least 4 ft in width]
• Raised median with curb
• Depressed median
• Two-way left turn lane
• Railroad or rapid transit
• Other divided

Source of Coding: Project Team

56. MEDIAN WIDTH
Definition: Median width, including inside shoulders
Attributes:

• Feet or meters

Source of Coding: HPMS

57. MEDIAN BARRIER TYPE
Definition: Median barrier type
Attributes:

• None
• Rigid barrier system (i.e., concrete)
• Semi-rigid barrier system (i.e., box beam, W-beam strong post, etc.)
• Flexible barrier system (i.e., cable, W-beam weak post, etc.),

Source of Coding: Based on SafetyAnalyst

58. MEDIAN (INNER) PAVED SHOULDER WIDTH
Definition: The width of the paved shoulder on the median (inner) side of the roadway on a divided roadway. Note that information on type, width and paved width of nonmedian shoulders is included in the Shoulder Descriptors. See definition of Left Shoulder Type.
Attributes:

• Feet or meters

Source of Coding: All sources

59. MEDIAN SHOULDER RUMBLE STRIP PRESENCE
Definition: Presence of median shoulder rumble strip
Attributes:

• Yes
• No

Source of Coding: Project Team

60. MEDIAN RUMBLE STRIP TYPE
Definition: Rumble strip type if present
Attributes:

• Milled
• Rolled
• Milled or rolled on edgeline
• Raised on edgeline

Source of Coding: Project Team

61. MEDIAN LEFT TURN LANE TYPE
Definition: Supplemental information on type of left turn lane in median. Note that basic information on number of median left turn lanes and the median turn-lane length should be captured under "Exclusive Left Turn Lane Presence" and "Exclusive Left Turn Lane Length" in the Lane Descriptors
Attributes:

• None
• Left-turn lane bays
• Directional left turn lane bays (to prevent crossing traffic from driveways)
• Offset left turn lanes (at intersection)

Source of Coding: Project Team

62. LEFT TURN LANE WIDTH
Definition: Width of median left turn lane
Attributes:

• Feet or meters

Source of Coding: All sources

I.D. SEGMENT ROADSIDE DESCRIPTORS

63. ROADSIDE CLEARZONE WIDTH
Definition: Roadside clearzone width
Attributes:

• Feet or meters

Source of Coding: Project Team

64. SIDESLOPE
Definition: Sideslope
Attributes:

• Numeric percent

Source of Coding: IHSDM

65. ROADSIDE RATING
Definition: A rating of the safety of the roadside from Appendix D, Publication No. FHWA-RD-99-207, Prediction of the Expected Safety Performance of Rural Two-Lane Highways. Collect only if clearzone width and sideslope are not collected.
Attributes:

• Roadside hazard is ranked on a seven-point categorical scale from 1 (best) to 7 (worst), based on a comparison with pictures in the report.

Source of Coding: IHSDM

66. DRIVEWAY INFORMATION
Definition: Driveway count by type
Attributes:

• Numeric

Source of Coding: Based on SafetyAnalyst, IHSDM

67. ROADSIDE HARDWARE DESCRIPTORS
Definition: Roadside hardware descriptors (including type, location, size, distance from lane edge). Examples include barrier (type and terminal type), signs (size, breakaway?), culverts, etc.
Attributes:

• Jurisdiction selected. Note that some Asset Management Systems may collect this information. If so link to that data.

Source of Coding: To be defined on the basis of Asset Management Systems

I.E. OTHER SEGMENT DESCRIPTORS

68. TERRAIN TYPE (E.G., MOUNTAINOUS, LEVEL)
Definition: Basic terrain type around segment. This is a (poor) surrogate for detailed data on curvature and grade, and would be collected only in the absence of those variables. See Alighnment variables below.
Attributes:

• Mountainous
• Rolling
• Level

Source of Coding: All sources

69. BRIDGE DESCRIPTORS FOR BRIDGES IN SEGMENT
Definition: Bridge descriptors for bridges in segment
Attributes:

• Link to National Bridge Index. See Appendix D.

Source of Coding: National Bridge Index

70. RR GRADE CROSSING DESCRIPTORS FOR CROSSINGS IN SEGMENT
Definition: RR grade crossing descriptors for crossings in segment
Attributes:

• Link to USDOT Highway-Rail Crossing Inventory. See Appendix D.

Source of Coding: USDOT National Highway-Rail Crossing Inventory

71. NUMBER OF SIGNALIZED INTERSECTIONS IN SECTION
Definition: Number of signalized intersections in section
Attributes:

• Numeric

Source of Coding: HPMS

72. NUMBER OF STOP-CONTROLLED INTERSECTIONS IN SECTION
Definition: Number of stop-controlled intersections in section
Attributes:

• Numeric

Source of Coding: HPMS

73. NUMBER OF UNCONTROLLED/OTHER INTERSECTIONS
Definition: Number of uncontrolled/other intersections
Attributes:

• Numeric

Source of Coding: HPMS

I.F. SEGMENT TRAFFIC FLOW DATA

74. AVERAGE DAILY TRAFFIC VOLUME
Definition: AADT
Attributes:

• Vehicles per day

Source of Coding: All sources

75. AADT YEAR
Definition: Year of AADT
Attributes:

• Numeric

Source of Coding: All sources

76. AADT ANNUAL ESCALATION PERCENTAGE
Definition: Expected annual percent growth in AADT, with "AADT YEAR" as base year. This will allow calculation of current year’s AADT if "AADT YEAR" differs from current year.
Attributes:

• Percent

Source of Coding: IHSDM

77. PERCENTAGE TRUCK OR TRUCK AADT
Definition: Percentage truck or truck AADT (includes tractor-semis and trucks with 6+ wheels)
Attributes:

• Percent or numeric count

Source of Coding: SafetyAnalyst

78. TOTAL DAILY TWO-WAY PEDESTRIAN COUNT/EXPOSURE
Definition: Total daily pedestrian flow in both directions (unless directional segment). This is a(poor) surrogate for crossing pedestrian counts.
Attributes:

• Average daily count (numeric)

Source of Coding: Project Team

79. BICYCLE COUNT/EXPOSURE
Definition: Total daily bicycle flow in both directions (unless directional segment)
Attributes:

• Average daily count (numeric)

Source of Coding: Project Team

80. MOTORCYCLE COUNT OR PERCENTAGE
Definition: Motorcycle daily count or percentage of AADT
Attributes:

• Percent or numeric count

Source of Coding: Project Team

81. HOURLY TRAFFIC VOLUMES (OR PEAK AND OFFPEAK AADT)
Definition: Hourly traffic volumes (or peak and offpeak AADT)
Attributes:

• Numeric count

Source of Coding: SafetyAnalyst

82. K-FACTOR
Definition: The K-factor is the 30th highest hourly volume (i.e., the design hour volume) for a year, as a percentage of the annual average daily traffic.
Attributes:

• Percent

Source of Coding: HPMS

83. FUTURE AADT
Definition: Forecasted AADT
Attributes:

• Vehicles per day

Source of Coding: HPMS

84. FUTURE AADT YEAR
Definition: Year of forecasted AADT
Attributes:

• Vehicles per day

Source of Coding: HPMS

85. DIRECTIONAL FACTOR
Definition: Proportion of peak hour traffic in the predominate direction of flow
Attributes:

• Proportion (numeric)

Source of Coding: HPMS

86. PERCENT COMBINATION TRUCKS - DAILY AVERAGE
Definition: Percent combination trucks - daily average
Attributes:

• Percent

Source of Coding: All sources

87. PERCENT SINGLE UNIT TRUCKS - DAILY AVERAGE
Definition: Percent single unit trucks - daily average
Attributes:

• Percent

Source of Coding: All sources

I.G. SEGMENT TRAFFIC OPERATIONS/CONTROL DATA

88. ONE/TWO-WAY OPERATIONS
Definition: Whether the segment operates as a one- or two-way roadway
Attributes:

• One-way
• Two-way
• One direction of travel for divided roadways

Source of Coding: SafetyAnalyst

89. SPEED LIMIT
Definition: Speed limit
Attributes:

• mph/kph

Source of Coding: All sources

90. SCHOOL ZONE INDICATOR
Definition: Whether segment contains a school zone
Attributes:

• Yes
• No

Source of Coding: Project Team

91. ON-STREET PARKING PRESENCE
Definition: Time-based parking restrictions
Attributes:

• Permitted 24 hrs/day
• Prohibited 24 hrs/day
• Permitted during specified times

Source of Coding: SafetyAnalyst, TSIMS

92. ON-STREET PARKING TYPE
Definition: On-street parking type
Attributes:

• No parking allowed
• Angle parking on one side
• Angle parking on both sides
• Parallel parking on one side
• Parallel parking on both sides

Source of Coding: HPMS and Project Team

93. ROADWAY LIGHTING
Definition: Type of roadway lighting
Attributes:

• None
• Spot on one-side
• Spot on both sides
• Continuous on one-side
• Continuous on both sides

Source of Coding: SafetyAnalyst

94. TRUCK ROUTE DESIGNATION
Definition: Truck route designation
Attributes:

• Designated truck route
• Not a designated truck route

Source of Coding: HPMS

95. TOLL FACILITY?
Definition: Whether the segment is a toll facility
Attributes:

• Toll segment
• Nontoll segment

Source of Coding: HPMS

96. EDGELINE PRESENCE/TYPE
Definition: Edgeline presence/type
Attributes:

• No marked edgeline
• Standard width edgeline
• Wide edgeline
• Other

Source of Coding: Project Team

97. CENTERLINE PRESENCE/TYPE
Definition: Centerline presence/type
Attributes:

• No marked centerline
• Standard centerline markings
• Centerline with centerline rumble strip

Source of Coding: Project Team

98. NO PASSING ZONE CODE/PASSING PERMISSIBILITY
Definition: No passing zone code/passing permissibility
Attributes:

• Percent of section length striped for passing

Source of Coding: HPMS

99. 85TH % SPEED
Definition: Traffic speed exceeded by 15 percent of the vehicles in the flow
Attributes:

• mph/kph

Source of Coding: SafetyAnalyst

II. ROADWAY ALIGNMENT DESCRIPTORS

(Note that these variables are best captured in a separate file that is linkable to inventory, crash, and other files.)

II.A. HORIZONTAL CURVE DATA

(Each data record will define an angle point or a single curve, even if the curve is a component of a compound or reverse curve. Spirals or other transitions are part of the curve.)

100. CURVE IDENTIFIERS AND LINKAGE VARIABLES
Definition: All variables needed to define location of each curve record and all variables necessary to link with other safety files.
Attributes:

• Route and location descriptors (e.g., route and beginning and ending milepoints or route and beginning and ending spatial coordinates). Must be consistent with other MMIRE files for linkage.

Source of Coding: All Sources

101. CURVE FEATURE TYPE
Definition: Type of horizontal alignment feature being described in the data record
Attributes:

• Horizontal angle point (i.e., joining of two tangents without a horizontal curve)
• Independent horizontal curve
• Component of compound curve (i.e., one curve in compound curve)
• Component of reverse curve (i.e., one curve in a reverse curve)

Source of Coding: Project Team

102. HORIZONTAL CURVE DEGREE OR RADIUS
Definition: Degree or radius of curve
Attributes:

• Numeric, feet or meters if radius

Source of Coding: All Sources

103. HORIZONTAL CURVE LENGTH
Definition: Length of curve including spiral
Attributes:

• Feet or meters

Source of Coding: All Sources

104. CURVE SUPERELEVATION OR SUPERELEVATION ADEQUACY
Definition: Either measured superelevation rate or percent or adequacy of superelevation when compared to AASHTO design standards
Attributes:

• Rate/percent or yes/no

Source of Coding: Project Team

105. HORIZONTAL TRANSITION/SPIRAL CURVE PRESENCE
Definition: Presence/type of transition from tangent to curve and curve to tangent
Attributes:

• No transition
• Spiral transition
• Other transition

Source of Coding: Project Team

106. HORIZONTAL CURVE INTERSECTION/DEFLECTION ANGLE
Definition: The angle between the two intersecting tangents in the direction of inventory(sometimes called the "deflection angle").
Attributes:

• Degrees. positive if angled right in the direction inventory and negative if angled left

Source of Coding: IHSDM

107. HORIZONTAL CURVE DIRECTION
Definition: Direction of curve in direction of inventory
Attributes:

• Right
• Left

Source of Coding: IHSDM

II.B. VERTICAL GRADE DATA

(Each data record will define an individual grade or the angle point or vertical curve linking two grades.)

108. GRADE IDENTIFIERS AND LINKAGE VARIABLES
Definition: All variables needed to define location of each vertical feature and all variables necessary to link with other safety files.
Attributes:

• Route/linear reference system descriptors (e.g., route and beginning and ending milepoints or route and beginning and ending spatial coordinates). Must be consistent with other MMIRE files for linkage.

Source of Coding: All sources

109. VERTICAL ALIGNMENT FEATURE TYPE
Definition: Type of vertical alignment feature being described in the data record
Attributes:

• Vertical angle point (i.e., joining of two vertical gradients without a verticle curve)
• Vertical gradient
• Sag vertical curve (i.e., vertical curve that connects a segment of roadway with a segment of roadway that has a more positive grade)
• Crest vertical curve (i.e., vertical curve that connects a segment of roadway with a segment of roadway that has a more negative grade)

Source of Coding: Project Team

110. PERCENT OF GRADIENT
Definition: Percent of gradient
Attributes:

• Percent

Source of Coding: All sources

111. GRADE LENGTH
Definition: Grade length
Attributes:

• Feet or meters

Source of Coding: All sources

112. VERTICAL CURVE LENGTH
Definition: Vertical curve length
Attributes:

• Feet or meters

Source of Coding: All sources

III. ROADWAY JUNCTION DESCRIPTORS

III.A. AT-GRADE INTERSECTION/JUNCTIONS

III.A.1. GENERAL DESCRIPTORS

113. UNIQUE INTERSECTION IDENIFIER
Definition: A numeric unique indentifer for each intersection/junction
Attributes:

• Node number, LRS of primary route, etc.

Source of Coding: Project Team

114. TYPE OF INTERSECTION/JUNCTION
Definition: Type of Junction being described in the data record
Attributes:

• Roadway/roadway (not interchange related)
• Roadway/roadway (interchange ramp terminal
• Roadway/pedestrian crossing (e.g., midblock crossing)
• Roadway/bicycle path or trail
• Roadway/railroad grade crossing
• Other

Source of Coding: Project Team

115. LOCATION IDENTIFIER FOR ROAD 1 CROSSING POINT
Definition: Location on the first intersecting route (e.g., route-milepost)
Attributes:

• Route and location descriptors (e.g., route and milepoint or route and spatial coordinates). Must be consistent with other MMIRE files for linkage.

Source of Coding: Project Team

116. LOCATION IDENTIFIER FOR ROAD 2 CROSSING POINT
Definition: Location on the second intersecting route (e.g., route-milepost)
Attributes:

• Route and location descriptors (e.g., route and milepoint or route and spatial coordinates). Must be consistent with other MMIRE files for linkage.

Source of Coding: Project Team

117. LOCATION IDENTIFIER FOR ROAD 3, 4, ETC., CROSSING POINT (E.G.,ROUTE-MILEPOST), ETC.
Definition: Location on the third and subsequent intersecting route (e.g., route-milepost)
Attributes:

• Route and location descriptors (e.g., route and milepoint or route and spatial coordinates).Must be consistent with other MMIRE files for linkage.

Source of Coding: Project Team

118. INTERSECTION/JUNCTION NO. OF LEGS
Definition: Intersection/junction no. of legs
Attributes:

• Numeric

Source of Coding: SafetyAnalyst

119. INTERSECTION/JUNCTION GEOMETRY
Definition: Intersection/junction geometry
Attributes:

• T
• Wye
• Cross
• More than four legs
• Roundabout

Source of Coding: Project Team

120. SCHOOL ZONE INDICATOR
Definition: Whether the intersection/junction is in a school zone
Attributes:

• Yes
• No

Source of Coding: Project Team

121. RAILROAD CROSSING NUMBER
Definition: Railroad crossing number if a RR grade crossing (for linkage to National Highway-Rail Crossing Inventory)
Attributes:

• Numeric

Source of Coding: Project Team

122. INTERSECTION SKEW ANGLE
Definition: Angle from perpendicular of intersection of the roads
Attributes:

• Degrees

Source of Coding: SafetyAnalyst

123. INTERSECTION/JUNCTION OFFSET
Definition: Whether crossroad approach centerlines are directly opposed or offset by some
Attributes:

• Yes
• No

Source of Coding: SafetyAnalyst

124. INTERSECTION/JUNCTION OFFSET DISTANCE
Definition: Distance that approach centerlines are offset
Attributes:

• Numeric (zero if not offset)

Source of Coding: SafetyAnalyst

125. INTERSECTION/JUNCTION TRAFFIC CONTROL
Definition: Traffic control present at intersection/junction
Attributes:

• Uncontrolled
• Two-way stop
• Four-way stop
• Yield sign
• Signalized (with ped signal)
• Signalized (w/o ped signal)
• Other

Source of Coding: Project Team

126. SIGNALIZATION TYPE (E.G., ACTUATED, FIXED, SYSTEM)
Definition: Type of signalization at intersection/junction
Attributes:

• No signal
• Uncoordinated fixed time
• Traffic actuated
• Linear coordination
• System coordination
• Pushbutton- acuated
• Other

Source of Coding: SafetyAnalyst and Project Team

127. NUMBER OF INTERSECTION/JUNCTION QUADRANTS WITH LIMITED SIGHT DISTANCE
Definition: Number of intersection/junction quadrants with limited sight distance
Attributes:

• Number of quadrants

Source of Coding: IHSDM

128. INTERSECTION/JUNCTION LIGHTING
Definition: Type of lighting at intersection/junction
Attributes:

• None
• Spot lighting at intersection
• Continuous segment lighting

Source of Coding: Project Team

129. ROUNDABOUT - NO. OF CIRCULATORY LANES
Definition: No. of circulatory lanes in roundabout
Attributes:

• Numeric

Source of Coding: Project Team

130. ROUNDABOUT—CIRCULATORY WIDTH
Definition: Width of the roadway between the central island and outer edge of the circulatory lane
Attributes:

• Feet or meters

Source of Coding: Project Team

131. ROUNDABOUT - INSCRIBED DIAMETER
Definition: Distance between the outer edges of the circulatory roadway
Attributes:

• Feet or meters

Source of Coding: Project Team

132. ROUNDABOUT—BICYCLE FACILITY
Definition: Type of bicycle facililty at roundabout
Attributes:

• None
• Separate cycle path
• Circulatory bike lane
• Other

Source of Coding: Project Team

III.A.2. AT-GRADE INTERSECTION/JUNCTION DESCRIPTORS (EACH APPROACH)

133. APPROACH AADT
Definition: AADT on approach described
Attributes:

• Vehicles per day

Source of Coding: All sources

134. APPROACH USE TYPE
Definition: Usage of approach
Attributes:

• Shared Use (e.g., vehicles, peds, bikes)
• Pedestrians Only
• Bicycles Only
• Pedestrians and Bicycles
• Railroad
• Other

Source of Coding: Project Team

135. APPROACH IS TWO-WAY, ONE-WAY
Definition: One-way or two-way flow on approach
Attributes:

• One-way
• Two-way
• One direction of travel for divided roadways

Source of Coding: All sources

136. NO. OF THRU LANES
Definition: Total number of thru lanes on approach, both directions
Attributes:

• Numeric

Source of Coding: All sources

137. NO. OF EXCLUSIVE LEFT TURN LANES
Definition: Number of exclusive left turn lanes on approach
Attributes:

• Numeric

Source of Coding: All sources

138. NO. OF EXCLUSIVE RIGHT TURN LANES
Definition: Number of exclusive right turn lanes on approach
Attributes:

• Numeric

Source of Coding: All sources

139. LENGTH OF EXCLUSIVE LEFT TURN LANES
Definition: Length of exclusive left turn lanes
Attributes:

• Feet or meters

Source of Coding: Project Team

140. LENGTH OF EXCLUSIVE RIGHT TURN LANES
Definition: Length of exclusive right turn lanes
Attributes:

• Feet or meters

Source of Coding: Project Team

141. MEDIAN TYPE AT INTERSECTION
Definition: Median type at intersection on approach
Attributes:

• None
• Curbed
• Not curbed
• Barrier

Source of Coding: Project Team

142. APPROACH TRAFFIC CONTROL
Definition: Traffic control present on approach
Attributes:

• Uncontrolled
• Stop sign
• Yield sign
• Traffic signal with ped signal
• Pedestrian signal only
• Other

Source of Coding: Project Team

143. LEFT-TURN PROTECTION
Definition: Presence and time of left turn protection
Attributes:

• Unsignalized
• Signalized with no left turn projection
• All-day protection
• Peak hour protection only
• Other

Source of Coding: Project Team

144. SIGNAL PROGRESSION
Definition: Signal progression on approach
Attributes:

• No signal
• Uncoordinated fixed time
• Traffic actuated
• Linear coordination
• System coordination
• Other

Source of Coding: SafetyAnalyst and Project Team

145. CROSSWALK PRESENCE/TYPE
Definition: Type of crosswalk
Attributes:

• Marked crosswalk
• Unmarked crosswalk
• Marked with refuge island
• Marked with in-street yield sign
• Marked with in-pavement warning lights
• Other

Source of Coding: Project Team

146. PEDESTRIAN SIGNALIZATION TYPE
Definition: Type of pedestrian signalizaton on approach
Attributes:

• Pushbutton actuated
• Recall (activated by traffic signal)
• Other

Source of Coding: Project Team

147. PEDESTRIAN SIGNAL SPECIAL FEATURES
Definition: Special features for either pushbutton or recall pedestrian signals
Attributes:

• Accessible pedestrian signal (i.e., audible tones for low-vision pedestrians)
• Countdown pedestrian signal
• Both accessible and countdown features
• Other

Source of Coding: Project Team

148. CROSSING PEDESTRIAN COUNT/EXPOSURE
Definition: Count or estimate of average daily pedestrian flow crossing this approach (Note: only applicable to approaches with vehicular traffic.)
Attributes:

• Numeric

Source of Coding: Project Team and SafetyAnalyst

149. LEFT/RIGHT TURN PROHIBITIONS
Definition: Left- or right turn prohibitions on this approach
Attributes:

• No left turns permitted at any time
• No left turn permitted during certain portions of the day
• No right turns permitted at any time
• No right turns permitted during certain portions of the day
• No U-turns

Source of Coding: Based on SafetyAnalyst

150. LEFT TURN COUNTS/PERCENT
Definition: Count or estimate of average daily left turns, or percent of total approach traffic turning left. (Note: This could also be captured for peak-periods only or by hour of day.)
Attributes:

• Count or percent

Source of Coding: Project Team

151. RIGHT TURN COUNTS/PERCENT
Definition: Count or estimate of average daily righ-turns, or percent of total approach traffic turning right. (Note: This could also be captured for peak-periods only or by hour of day.)
Attributes:

• Count or percent

Source of Coding: Project Team

152. TRANSVERSE RUMBLE STRIP PRESENCE
Definition: Presence of transverse rumble strip on approach
Attributes:

• Yes
• No

Source of Coding: Project Team

153. ROUNDABOUT—ENTRY WIDTH
Definition: Full width of entry where it meets the inscribed circle. Note that total width of the approach can be derived from totaling entry width, exit width and splitter island width.
Attributes:

• Feet or meters

Source of Coding: Project Team

154. ROUNDABOUT—NUMBER OF ENTRY LANES
Definition: Number of entry lanes into roundabout on this approach
Attributes:

• Numeric

Source of Coding: Project Team

155. ROUNDABOUT—ENTRY RADIUS
Definition: Minimum radius of curvature of the curb on the right side of the entry.
Attributes:

• Feet or meters

Source of Coding: Project Team

156. ROUNDABOUT—EXIT WIDTH
Definition: Full width of exit where it meets the inscribed circle. Note that total width of the approach can be derived from totaling entry width, exit width and splitter island width.
Attributes:

• Feet or meters

Source of Coding: Project Team

157. ROUNDABOUT—NUMBER OF EXIT LANES
Definition: Number of exit lanes from roundabout on this approach leg.
Attributes:

• Numeric

Source of Coding: Project Team

158. ROUNDABOUT—EXIT RADIUS
Definition: Minimum radius of curvature of the curb on the right side of the exit.
Attributes:

• Feet or meters

Source of Coding: Project Team

159. ROUNDABOUT—PEDESTRIAN FACILITY
Definition: Type of pedestrian crossing facility on this approach to roundabout
Attributes:

• Marked crosswalk with raised splitter island
• Marked crosswalk with flush splitter island
• Unmarked crosswalk with raised splitter island
• Unmarked crosswalk with flush splitter island
• Other

Source of Coding: Project Team

160. ROUNDABOUT—CROSSWALK LOCATION (DISTANCE FROM YIELD LINE)
Definition: Location of marked pedestrian crosswalk relative to yield line
Attributes:

• Feet or meters

Source of Coding: Project Team

161. ROUNDABOUT—SPLITTER ISLAND WIDTH
Definition: Width of the splitter island separating entry and exit legs (measured at the inscribed circle).
Attributes:

• Feet or meters

Source of Coding: Project Team

III.B. INTERCHANGE AND RAMP DESCRIPTORS

III.B.1. GENERAL INTERCHANGE DESCRIPTORS

162. UNIQUE INTERCHANGE IDENIFIER
Definition: A numeric unique indentifer for each interchange
Attributes:

• Node number, LRS of primary route, etc.

Source of Coding: Project Team

163. LOCATION IDENTIFIER FOR ROAD 1 CROSSING POINT
Definition: Location on the first intersecting route (e.g., route-milepost)
Attributes:

• Route and location descriptors (e.g., route and milepoint or route and spatial coordinates). Must be consistent with other MMIRE files for linkage.

Source of Coding: Project Team

164. LOCATION IDENTIFIER FOR ROAD 2 CROSSING POINT
Definition: Location on the second intersecting route (e.g., route-milepost)
Attributes:

• Route and location descriptors (e.g., route and milepoint or route and spatial coordinates). Must be consistent with other MMIRE files for linkage.

Source of Coding: Project Team

165. LOCATION IDENTIFIER FOR ROAD 3, 4, ETC., CROSSING POINT
Definition: Location on the third and subsequent intersecting route (e.g., route-milepost)
Attributes:

• Route and location descriptors (e.g., route and milepoint or route and spatial coordinates). Must be consistent with other MMIRE files for linkage.

Source of Coding: Project Team

166. INTERCHANGE TYPE (DIAMOND, CLOVER, ETC.)
Definition: Type of interchange
Attributes:

• Diamond
• Full cloverleaf
• Partial cloverleaf
• SPUI
• Other

Source of Coding: Project Team

167. INTERCHANGE LIGHTING
Definition: Type of interchange lighting
Attributes:

• None
• Full interchange-area lighting
• Partial interchange lighting
• Continuous lighting on one or more approach roads
• Other

Source of Coding: Project Team

III.B.2. INTERCHANGE RAMP DESCRIPTORS

(NOTE that each ramp in an interchange is described by the following variables. Thus, each ramp record includes a full description of an individual ramp. If a ramp splits into two ramps, a new record is generated for the second and all subsequent ramps.)

168. UNIQUE RAMP IDENTIFIER
Definition: An identifier for each ramp that is part of a given interchange. This defines which ramp the following variables are describing.
Attributes:

• Alpa or Numeric—each set of interchange ramps could begin with "1" or "A" Source of Coding: Project Team

Source of Coding: Project Team

169. RAMP LENGTH
Definition: Length of ramp
Attributes:

• Miles, feet or meters

Source of Coding: SafetyAnalyst

170. RAMP NO. OF LANES
Definition: Number of lanes on ramp
Attributes:

• Numeric

Source of Coding: SafetyAnalyst

171. RAMP AADT
Definition: AADT on ramp
Attributes:

• Numeric

Source of Coding: All source

172. RAMP POSTED SPEED LIMIT
Definition: The posted (not advisory) speed limit on the ramp
Attributes:

• Numeric
• No posted limit (i.e., limit will be the same as on the connecting roadways)

Source of Coding: Project Team

173. FEATURE AT BEGINNING RAMP TERMINAL
Definition: A ramp is described by a beginning and ending ramp terminal in the direction of inventory. This variable describes the type of feature intersecting with the ramp at the beginning terminal.
Attributes:

• Freeway
• Nonfreeway (surface street)
• Other ramp
• Frontage road
• Other

Source of Coding: Project Team

174. RAMP DESCRIPTOR AT BEGINNING RAMP TERMINAL
Definition: Description of the beginning terminal of the ramp
Attributes:

• Acceleration Lane
• Deceleration Lane
• Weaving lane (e.g., the weaving area joining two ramps under an overpass in a cloverleaf interchange)
• Intersection with roadway—ramp stop/yield controlled
• Intersection with roadway—ramp signal controlled
• Another ramp
• Other

Source of Coding: Project Team

175. LOCATION IDENTIFIER FOR ROADWAY AT BEGINNING RAMP TERMINAL
Definition: Location on the roadway at the beginning ramp terminal (e.g., route-milepost for that roadway) if the ramp connects with a roadway at that point.
Attributes:

• Route and location descriptors (e.g., route and milepoint or route and spatial coordinates)for the roadway intersected at the beginning ramp terminal. Must be consistent with other MMIRE files for linkage.
• NA (Not applicable) if beginning terminal is not at a roadway (e.g., another ramp)

Source of Coding: Project Team

176. ROADWAY TRAFFIC FLOW DIRECTION AT BEGINNING RAMP TERMINAL
Definition: Ramps can intersect a roadway on either of two sides. This defines the side of the road intersected by the ramp.
Attributes:

• Increasing direction of flow (with respect to roadway inventory direction)
• Decreasing direction of flow (with respect to roadway inventory direction)
• NOTE—Alternative coding could be compass direction of flow

Source of Coding: Project Team

177. FEATURE AT ENDING RAMP TERMINAL
Definition: A ramp is described by a beginning and ending ramp terminal in the direction of inventory. This variable describes the type of feature intersecting with the ramp at the ending terminal.
Attributes:

• Freeway
• Nonfreeway (surface street)
• Other Ramp
• Frontage road
• Other

Source of Coding: Project Team

178. RAMP DESCRIPTOR AT ENDING RAMP TERMINAL
Definition: Description of the ending terminal of the ramp
Attributes:

• Acceleration Lane
• Deceleration Lane
• Weaving lane (e.g., the weaving area joining two ramps under an overpass in a cloverleaf interchange)
• Intersection with roadway—ramp stop/yield controll
• Intersection with roadway—ramp signal controlled
• Another ramp
• Other

Source of Coding: Project Team

179. LOCATION IDENTIFIER FOR ROADWAY AT ENDING RAMP TERMINAL
Definition: Location on the roadway at the beginning ramp terminal (e.g., route-milepost for that roadway) if the ramp connects with a roadway at that point.
Attributes:

• Route and location descriptors (e.g., route and milepoint or route and spatial coordinates) for the roadway intersected at the ending ramp terminal. Must be consistent with other MMIRE files for linkage.
• NA (Not applicable) if ending terminal is not at a roadway (e.g., another ramp)

Source of Coding: Project Team

180. ROADWAY TRAFFIC FLOW DIRECTION AT ENDING RAMP TERMINAL
Definition: Ramps can intersect a roadway on either of two sides. This defines the side of the road intersected by the ramp.
Attributes:

• Increasing direction of flow (with respect to roadway inventory direction)
• Decreasing direction of flow (with respect to roadway inventory direction)
• NOTE—Alternative coding could be compass direction of flow

Source of Coding: Project Team

Previous | Table of Contents | Next

FHWA-HRT-07-046

TFHRC Home | FHWA Home | Feedback United States Department of Transportation - Federal Highway Administration