In many cases, roadway inventory data may be available as an additional source to help relate problems to candidate strategies. Where the scope of the analysis is limited to a relatively small portion of the road system, field studies can provide needed details to help select the appropriate strategies to consider. Other sources of data are sometimes available, as well, which can help in the analysis. Details of the problem identification process are covered in the discussion of Step 1 of the Model Implementation Process.
Many of the strategies listed in the guide for run-off-road crashes are potentially applicable to several of the crash factors. Even where this is not the case, it may occur that more than one crash factor will be identified as significantly associated with the problem. In these cases, the sum of strategies associated with each of the factors, as listed in Exhibit 1, should be considered.
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Exhibit 1 – Linkage Between Crash Factors and Candidate "Encroachment Reducing" Strategies |
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Crash Factors |
MMUCC Element No. |
Candidate Strategy |
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Contributing Road Factors |
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Pavement Skid Resistance |
|
15.1 A7 – provide skid-resistant pavement surfaces
|
|
Standing Water on Pavement |
C15 (C13) |
|
Snow or Ice on Pavement |
C15 (C13) |
|
Shoulder condition |
C15 |
15.1 A8 – eliminate shoulder drop-offs (see "Shoulder Treatments")
15.1 A8 – widen or pave shoulder (see "Shoulder Treatments") |
|
Contributing Driver Factors |
|
Swerving/avoiding slippery surface, vehicle, etc.
(Note, check location-type variable to see whether the "swerving" was on a tangent or curve, or was due to slippery pavement) |
P14 |
15.1 A4 – provide enhanced delineation of sharp curves
15.1 A5 – provide improved highway geometry for horizontal curves
15.1 A6 – provide improved pavement markings
15.1 A7 – provide skid-resistant pavement surfaces
15.1 A8 – widen or pave shoulder (see "Shoulder Treatments") |
|
Over-correcting/over-steering |
P14 |
15.1 A4 – provide enhanced delineation of sharp curves
15.1 A5 – provide improved highway geometry for horizontal curves
15.1 A6 – provide improved pavement markings
15.1 A8 – eliminate shoulder drop-offs (see "Shoulder Treatments")
15.1 A8 – widen or pave shoulder (see "Shoulder Treatments") |
|
Inattention/distracted |
P14 |
15.1 A1 – install shoulder rumble strips
15.1 A2 -- install (experimental) rumble strips for roads with narrow or no paved shoulders
15.1 A3 - install (experimental) mid-lane rumble strips
15.1. A4 – provide enhanced delineation of sharp curves
15.1 A6 – provide improved pavement markings
15.1 A8 – widen or pave shoulder (see "Shoulder Treatments") |
|
Fatigued/asleep |
P14, P15 |
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Under the influence |
P15 |
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Environmental Factors |
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Weather (Rain, sleet, snow)
|
C11 |
15.1 A1 – install shoulder rumble strips
15.1 A2 -- install (experimental) rumble strips for roads with narrow or no paved shoulders
15.1 A3 - install (experimental) mid-lane rumble strips
15.1 A4 – provide enhanced delineation of sharp curves
15.1.1.7 – provide skid-resistant pavement surfaces
15.1.1.5 – provide improved pavement markings |
|
Road Surface Condition (Wet, snow, ice, water, slush) |
C14 |
|
Ambient light condition -- dark |
C4 |
15.1 A1 – install shoulder rumble strips
15.1 A2 -- install (experimental) rumble strips for roads with narrow or no paved shoulders
15.1 A3 - install (experimental) mid-lane rumble strips
15.1 A4 – provide enhanced delineation of sharp curves
15.1 A6 – provide improved pavement markings |
|
Animal in road |
C14 |
15.1 A8 – widen or pave shoulder (see "Shoulder Treatments") |
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Nature of Crash |
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Off of curve
(Note: While MMUCC requires curve-presence from links with roadway inventory data, many state crash-report forms include a variable noting curve or grade.) |
RL2 |
15.1 A1 - install shoulder rumble strips
15.1 A2 -- install (experimental) rumble strips for roads with narrow or no paved shoulders
15.1 A3 - provide enhanced delineation of sharp curves
15.1 A5 - provide improved highway geometry for horizontal curves
15.1 A8 – widen or pave shoulder (see "Shoulder Treatments") |
|
Off (of tangent) right or left |
V23 |
15.1 A1 – install shoulder rumble strips
15.1 A2 -- install (experimental) rumble strips for roads with narrow or no paved shoulders
15.1. A3 - install (experimental) mid-lane rumble strips
15.1 A6 – provide improved pavement markings
15.1 A8 – widen or pave shoulder (see "Shoulder Treatments") |
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First Harmful Event, Most Harmful Event or last event in Sequence of Events – Overturn |
C2, C12, C6 |
15.1 B2 Design safer slopes and ditches to prevent rollovers (See "Improving Roadsides")
15.1 B3 Remove/relocate objects in hazardous locations (See "Improving Roadsides")
15.1 C1 Improve design of roadside hardware (e.g., light poles, signs, bridge rails) (See "Improving Roadsides")
15.1 C2 Improve design and application of barrier and attenuation systems (See "Improving roadsides")
15.1 B3: Delineate roadside objects (experimental treatment)
(Note: Also see Guides on "Trees in Hazardous Locations" and "Utility Poles") |
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First Harmful Event, Most Harmful Event or last event in Sequence of Events -- Fixed Object
(Note: Look for patterns among types of objects – guardrail, tree, utility pole, etc.) |
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Environment of Crash |
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(Note: The following variables are not always on the crash report and will need to be extracted from existing roadway inventories and linked to crashes based on crash location – i.e., route/milepost, GIS coordinates, etc.) |
|
Shoulder width -- narrow |
RL6 |
15.1 A2 -- install (experimental) rumble strips for roads with narrow or no paved shoulders
15.1 A2 - install (experimental) mid-lane rumble strips
15.1 A3 – provide enhanced delineation of sharp curves
15.1 A6 – provide improved pavement markings
15.1 B8 – widen and/or pave shoulders (see "Shoulder Treatments") |
|
Shoulder Type -- unpaved |
ANSI D20 (HPMS/90,
item 44) |
15.1 A1 – install edgeline rumble strips (see Strategy 15.1 A2 Rumble Strips for Roads with Narrow or No Paved Shoulders (Experimental Treatment)"
15.1 A3 - install (experimental) mid-lane rumble strips
15.1 A4 – provide enhanced delineation of sharp curves
15.1 A6 – provide improved pavement markings
15.1 A8 – widen and/or pave shoulders (see "Shoulder Treatments")
15.1. A8 – eliminate shoulder dropoff (see "Shoulder Treatments") |
|
Horizontal Alignment – sharper curves |
RL2 |
15.1 A4 – provide enhanced delineation of sharp curves
15.1 A5 – provide improved highway geometry for horizontal curves
15.1 A6 – provide improved pavement markings
15.1 B1 - Design safer slopes and ditches to prevent rollovers (See "Improving Roadsides")
15.1 B2 - Remove/relocate objects in hazardous locations (See "Improving Roadsides") |