In 2010, 51,664 crashes occurred in Nevada. Only about 9% of those crashes occurred in rural areas of the state. However, if only fatal crashes are considered, 41% of those fatal crashes occurred in rural areas. Generally, speed zones are provided in towns along rural highways to reduce speed-related crashes. However, a guideline is necessary for a consistent procedure to setup speed zones throughout the state. The main objectives of this study are to determine factors associated with crashes and to identify the best practices for setting up speed zones in towns along rural highways.

Eleven towns along rural highways of Nevada were identified by the Nevada Department of Transportation (NDOT) Technical Advisor Panel (TAP) for crash data analysis. Ten year of crash data for these towns were collected and analyzed. The result showed that the percentage of fatal crashes in these towns was 0.89% for 9 years. For all the rural areas in Nevada, the percentage of fatal crashes in 2010 was 2.00%. Regression analyses showeda strong correlation between the number of crashes and the percentage of vehicles exceeding posted speed limitsin these towns.

Based on the survey data and various state DOT speed limit guidelines,the 85thpercentile speed was the most important factor for determining the speed limit for a speed zone. Ifproper enforcementis ensured, speed zones can be effective toreduce the number of crashesin towns along rural highways.

The study results will assist in formulating a speed-zone guideline for towns along the rural highways of Nevada. Recommendations to prepare the speed-zone guideline are provided as well as the limitations of the study.