| Countermeasure | CRFs | ||||
| Average CRF from county engineer’s survey (%) | CRF from FHWA report (%) [12] | % of survey responses matching the FHWA CRFs | CRF from the surveys in the FHWA’s CRF range? (Yes/No) | ||
| Fixed-object crash type | |||||
| Widen shoulder (paved) | 34.8 | 15 - 62 | 90% | Yes | |
| Widen shoulder (unpaved) | 23.1 | 13 - 43 | 80% | Yes | |
| Remove or relocate fixed objects outside the clear zone | 67.6 | 40 - 100 | 60% | Yes | |
| Widen the clear zone | 28.4 | 13 - 44 | 50% | Yes | |
| Improve pavement friction (grooving) | 22 | 19 - 36 | 77% | Yes | |
| Install edge-line markings | 59.6 | 59 - 66 | 100% | Yes | |
| Improve guardrail | 16.17 | 18 - 21 | 67% | No | |
| Install guardrail (as shield for rocks and posts) | 81.1 | 100 | 80% | No | |
| Install impact attenuators | 46.1 | 69 | 50% | No | |
| Flatten horizontal curve | 61.5 | 68 - 87 | 77% | No | |
| Flatten side slopes | 50.7 | 62 | 80% | No | |
| Improve pavement friction (overlay) | 35 | 43 | 80% | No | |
| Improve pavement friction (resurface with open-graded mix) | 75 | 93 | 80% | No | |
| Install or upgrade curbing | 39.6 | 50 | 67% | No | |
| Run-off-road crash type | |||||
| Install guardrail (at embankment) | 22.8 | 7 - 47 | 67% | Yes | |
| Flatten horizontal curve | 75.2 | 79 - 90 | 89% | Yes | |
| Flatten side slopes | 17 | 10 - 24 | 70% | Yes | |
| Widen lane | 25.6 | 12 - 49 | 80% | Yes | |
| Widen shoulder (paved) | 35.4 | 60 - 16 | 73% | Yes | |
| Widen shoulder (unpaved) | 23.7 | 13 - 43 | 70% | Yes | |
| Improve pavement friction (groove shoulder) | 27.8 | 27 - 41 | 80% | Yes | |
| Install shoulder rumble strips | 23.1 | 7 - 41 | 77% | Yes | |
| Install edge-line markings | 25.3 | 25 - 30 | 100% | Yes | |
| Improve guardrail | 26.7 | 28 - 41 | 67% | No | |
| Improve super-elevation | 44.6 | 50 | 89% | No | |
| Remove or relocate fixed objects outside the clear zone | 64.2 | 71 | 77% | No | |
| Install curve advance-warning signs | 28.1 | 30 | 80% | No | |
| Install delineators (general) | 33.7 | 34 | 80% | No | |
| Improve pavement friction (overlay) | 23 | 28 | 80% | No | |
| Overturned crash type | |||||
| Improve guardrail | 31.2 | 27 - 41 | 80% | Yes | |
| Install guardrail (at bridge) | 32.8 | 32 - 41 | 90% | Yes | |
| Flatten horizontal curve | 43.6 | 24 - 73 | 90% | Yes | |
| Remove or relocate fixed objects outside the clear zone | 35.1 | 42 - 44 | 77% | No | |
| Improve pavement friction (grooving) | 35.2 | 35 - 54 | 77% | No | |