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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation
FHWA Highway Safety Programs

Report Organization

The remainder of this report is organized into eight sections as follows:

THE SAFETY OF SPEED: As speed limits are first and foremost a road safety measure, a discussion on the effects of speed on crash risk is provided for the information of the user.

SPEED LIMIT BASICS: An introduction to the broad categories and types of speed limits, including statutory speed limits, prima facie speed limits, and speed zoning.

SETTING SPEED LIMITS: A detailed description of the various methods that are available for setting speed limits, a brief discussion of special types of speed limits (i.e., nighttime speed limits, school zone speed limits, truck speed limits, etc.), and information on minimum lengths of speed zones.

SPEED LIMIT SIGN DESIGN AND PLACEMENT: Criteria that are used in selecting sign types and in the placement of the signs for speed zones and speed transitions. Also included is some information on Speed Feedback signs.

SPEED STUDY DATA COLLECTION: An outline of the data required for determining a posted speed limit with emphasis on spot speed data collection and analysis.

SPEED LIMIT ENFORCEMENT: A brief discussion on the role of engineering practitioners in assisting with the enforcement of speed limits.

CASE STUDIES: Two case studies that demonstrate the use of several available methods for setting speed limits.

REFERENCES AND APPENDICES: Supporting information and additional details for the reader.