00603695

Component

http://onlinepubs.trb.org...trr/1990/1281/1281-005.pdf

https://scholar.google.co...avis&publication_year=1990

As early as 1947, studies concluded that the majority of drivers ignore speed limits and drive at speeds that they believe are safe and reasonable. Since then, some studies have supported this conclusion whereas others indicated that speed limits do affect travel speeds in varying degrees. In an FHWA-sponsored assessment of current speed zoning criteria, speed and accident data were collected at 50 locations, both urban and rural, in four states on roadways with posted speed limits ranging from 25 to 55 mph. These data were analyzed to determine travel speed characteristics, compliance with posted speed limits, and the point of minimum accident risk. Significant findings were as follows: Mean speeds exceeded posted speed limits by 1 to 8 mph; 85th-percentile speeds ranged from 6 to 14 mph over the posted speed limit, or 4 to 7 mph over the mean speed; the majority (70.2%) of free-flow drivers observed did not comply with posted speed limits; in general, 85% compliance was achieved at speeds 10 mph over the posted speed limit; accident rates for the 25-mph zones were consistently much higher than for any of the other zones; and the speed at which accident risk was minimized occurred at the 90th percentile of the travel speeds observed.

This paper appears in Transportation Research Record No. 1281, Human Factors and Safety Research Related to Highway Design and Operation. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

00620496

p. 40-51

1990

Transportation Research Record

0-309-05060-X

Figures (9) ; References (6) ; Tables (14)

85th percentile speed; Compliance; Crash rates; Data collection; Field studies; Hazards; Risk assessment; Rural areas; Speed limits; Speed zones; Urban areas

Criteria

Highways; Operations and Traffic Management; Safety and Human Factors; I73: Traffic Control; I83: Accidents and the Human Factor

TRIS, TRB, ATRI

Feb 28 1991 12:00AM

• BEHAVIORAL MODEL OF FREEWAY EXITING
• EFFECT OF THE 65-MPH SPEED LIMIT ON SPEEDS IN THREE STATES
• ESTIMATING AND UPDATING FLOWS ON PEDESTRIAN FACILITIES IN THE CENTRAL BUSINESS DISTRICT
• MEASUREMENT OF PEDESTRIAN FLOW DATA USING IMAGE ANALYSIS TECHNIQUES
• MOTORIST BEHAVIOR AND THE DESIGN OF MOTORIST INFORMATION SYSTEMS
• MOTORIST COMPREHENSION OF SIGNING APPLIED IN URBAN ARTERIAL WORK ZONES
• MOTORIST INFORMATION SYSTEMS AND RECURRENT TRAFFIC CONGESTION: SENSITIVITY ANALYSIS OF EXPECTED RESULTS
• MOTORIST UNDERSTANDING OF AND PREFERENCES FOR LEFT-TURN SIGNALS
• NON-EUCLIDEAN METRICS IN NONMOTORIZED TRANSPORTATION
• OPERATIONAL EFFECTIVENESS OF TRUCK LANE RESTRICTIONS
• OPERATIONAL EFFECTS OF LARGER TRUCKS ON RURAL ROADWAYS
• PERFORMANCE DIFFERENCES ON DRIVING AND LABORATORY TASKS BETWEEN DRIVERS OF DIFFERENT AGES
• PRELIMINARY ASSESSMENT OF THE INCREASED SPEED LIMIT ON RURAL INTERSTATE HIGHWAYS IN ILLINOIS (ABRIDGMENT)
• RELATIONSHIP BETWEEN CHILD PEDESTRIAN ACCIDENTS AND CITY PLANNING IN ZARQA, JORDAN
• RELATIONSHIP OF 65-MPH LIMIT TO SPEEDS AND FATAL ACCIDENTS
• RURAL ACCIDENT RATE VARIATIONS WITH TRAFFIC VOLUME
• T-INTERSECTION SIMULATOR PERFORMANCE OF DRIVERS WITH PHYSICAL LIMITATIONS