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Synthesis of Safety Research Related to Speed and Speed Management - Turner-Fairbank.. Page 19 off 25
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<br />on freeways and other high-speed roads, speed limit increases generally lead to higher speeds
<br />and crashes. The change in speed is roughly one-fourth the change in speed limit. Results from
<br />international studies suggest that for every 1 mi/h change in speed, injury accidents will change
<br />by 5 percent (3 percent for every lkm/h). However there is limited evidence that suggests the net
<br />effect of speed limits may be positive on a system wide basis. More research is needed to
<br />evaluate the net safety effect of speed limit changes.
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<br />Most of the speed related crashes involve speed too fast for conditions. This would suggest that
<br />variable speed limits that adjust with traffic and environmental conditions could provide potential
<br />benefits.
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<br />Despite the large number of references concerning traffic calming, very few reports include
<br />results of a systematic evaluation. In many cases traffic volumes as well as speed are reduced.
<br />As a result of the traffic diversion, crashes may be migrating to other roads. More research is
<br />needed to assess the system wide impacts and permit comparisons to be made among individual
<br />as well as combinations of traffic calming measures.
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<br />References
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<br />N.N. Bowie, Jr. and M. Waltz, "Data Analysis of the Speed-Related Crash Issue," Auto and
<br />Traffic Safety, Vol. 2, Winter 1994.
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<br />J. R. Treat, N. S. McDonald, D. Shinar, R. D. Hume, R. E. Mayer, R. L. Stansifer, and N. J.
<br />Castellan, "Tri-bevel Study of the Causes of Traffic Accidents, Vol. I: Causal Factor
<br />Tabulations and Assessment," Report No. DOT HS 805B085, National Highway Traffic Safety
<br />Administration, 1977.
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<br />D. Solomon, "Accidents on Main Rural Highways Related to Speed, Driver, and Vehicle,"
<br />Federal Highway Administration, Washington, DC, July 1964 (Reprinted 1974).
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<br />J. A. Cirillo, "Interstate System Accident Research Study II, Interim Report II," Public Roads,
<br />Vol. 35, No. 3, August 1968.
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<br />Reseamh Triangle Institute, "Speed and Accident, Volume I1", Report No. FH-11-6965,
<br />National Highway Safety Bureau, June 1970.
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<br />L. B. West, Jr. and J. W. Dunn, "Accidents, Speed Deviation and Speed Limits," Traffic
<br />Engineering, Vol. 41, No. 10, July 1971.
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<br />J. M. Munden, "The Relation Between A Driver's Speed and His Accident Rate," Report LR
<br />88, Transport and Road Research Laboratory, Crowthorne, England, 1967.
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<br />B. N. Fildes, G. Rumbold, and A. Leening, "Speed Behavior and Drivers' Attitude to
<br />Speeding," Report No. 16, Monash University Accident Research Centre, Victoria, Australia,
<br />June 1991.
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<br />B. N. Fildes and S. J. Lee, "The Speed Review: Road Environment, Behavior, Speed Limits,
<br />Enforcement and Crashes," Report No. CR 127, Federal Office of Road Safety, Canberra,
<br />Australia, September 1993.
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<br />D. L. Harkey, H. D. Robertson, and S. E. Davis, "Assessment of Current Speed Zoning
<br />Criteria," Transportation Research Record 1281, Transportation Research Board, Washington,
<br />DC, 1990.
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<br />E. Hauer, "Accidents, Overtaking and Speed Control," Accident Analysis and Prevention, Vol.
<br />3, No. 1, July 1971.
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<br />http://www.ntl.bts.gov/ntl/DOCS/speed/speed.htm 07/19/2000
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