Model Inventory of Roadway Elements – MIRE, Version 1.0
67. Roadside Rating
Definition: A rating of the safety of the roadside, ranked on a seven-point categorical scale from 1 (best) to 7 (worst).
Attributes:
- Rating = 1
- Wide clear zones greater than or equal to 30 ft from the pavement edgeline.
- Sideslope flatter than 1:4.
- Recoverable.
- Rating = 2
- Clear zone between 20 and 25 ft from pavement edgeline.
- Sideslope about 1:4.
- Recoverable.
- Rating = 3
- Clear zone about 10 ft from pavement edgeline.
- Sideslope about 1:3 or 1:4.
- Rough roadside surface.
- Marginally recoverable.
- Rating = 4
- Clear zone between 5 to 10 ft from pavement edgeline.
- Sideslope about 1:3 or 1:4.
- May have guardrail (5 to 6.5 ft from pavement edgeline).
- May have exposed trees, poles, or other objects (about 10 ft from pavement edgeline).
- Marginally forgiving, but increased chance of a reportable roadside collision.
- Rating = 5
- Clear zone between 5 to 10 ft from pavement edgeline.
- Sideslope about 1:3.
- May have guardrail (0 to 5 ft from pavement edgeline).
- May have rigid obstacles or embankment within 6.5 to 10 ft of pavement edgeline.
- Virtually non-recoverable.
- Rating = 6
- Clear zone less than or equal to 5 ft.
- Sideslope about 1:2.
- No guardrail.
- Exposed rigid obstacles within 0 to 6.5 ft of the pavement edgeline.
- Non-recoverable.
- Rating = 7
- Clear zone less than or equal to 5 ft.
- Sideslope 1:2 or steeper.
- Cliff or vertical rock cut.
- No guardrail.
- Non-recoverable with high likelihood of severe injuries from roadside collision.
See Figure 4 for additional detail.
Priority: Critical Alternative
HPMS/Tool Requirements: HSM/IHSDM (Required)
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Figure 4. Illustration of Roadside Ratings.
Source: Zegeer, C.V., J. Hummer; D. Reinfurt; L. Herf; and W. Hunter (1986). Safety Effects of Cross-Section Design for Two-Lane Roads, FHWA-RD-87-008, Federal Highway Administration, Washington, DC.