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Synthesis of Safety Research Related to Speed and Speed Management - Turner-Fairbank.. Page 15 of' 25 Casey and Lund (1990) found that the presence of a speed feedback indicator decreased speeds at a placement site and for a shod distance past the site. No speed reduction was noted after the indicator was removed. Speed reduction decay rates downstream from the location of the indicator were significantly prolonged when minimal traffic enforcement activities were conducted in the area immediately surrounding the location of the indicator. Perrillo (1997) observed speed reductions of 2-3 mi/h (3-5 kin/h) in the vicinity of the speed feedback trailers for the two days they were in place on four residential streets in Texas. Speed returned to their previous level as soon as the indicator was removed. Dart and Hunter (1976) evaluated the effects of four speed enforcement techniques, one of which was a speed indicator. The other techniques included a speed check zone, a stationary patrol car, and a simulated pullover. The speed indicator was not combined with any other enforcement technique. While all of the other techniques had a significant impact on reducing speeds at enforcement sites, the speed indicator had no significant effect on traffic speeds. Hamalainen and Hassel (1990) describe a well-publicized speed indicator pro-gram carried out in Finland. Reduced speeds were noted while the indicator was pre-sent, and the speed halo effect lasted up to 10 km after the location of the display. The incidence of overtaking also was reduced. This reduction in passing behavior exhibited a time halo effect, continuing for a short period after the end of the experiment. It is not clear from the report whether the speed indicator was combined with other speed enforcement techniques. Public Information And Education (PI&E) A large proportion of the citations reviewed concerning speed enforcement mention some form of public information or educational program, or publicity. None attributed a significant reduction in speed, speeding, crashes, or crash severity to any such campaign that was not closely tied to an enfomement or engineering program. Traffic Enforcement Notification Signs Another innovative means of speed enforcement that emphasizes increasing driver awareness of speed is the use of portable traffic enforcement warning signs. The signs are placed at each end of a targeted roadway just prior to an enforcement period. During the enforcement period, officers write citations for all traffic and vehicle violations occurring within the target area. There was a 17 percent reduction in injury crashes in Huntington Beach and fatal crashes had decreased by 100 percent between the introduction of the traffic enforcement and warning sign program and Stuster's (1995) survey. The Racine, Wisconsin, Police Department established a program in 1983 to reduce crashes at the most dangerous intersections in the city (Stuster, 1995). The "EZ" pro-gram created enforcement zones around each of the ten most dangerous intersections. All traffic safety laws within the zones (including speed limit laws) were strictly enforced. A unique feature of the EZ program was the use of pole wraps placed on every light pole within one block of a targeted intersection to remind drivers that intensified traffic enforcement was being conducted in the area. Traffic officers issued written warnings in the form of EZ "contact. cards" (instead of citations) for minor traffic infractions within the zones. Each contact card listed the ten dangerous intersections and encouraged drivers to drive more safely in Racine. EZ contact cards also were issued to motorists who drove safely through the enforcement zones. These commendation contact cards were put into drawing for prizes supplied by the police department. The community realized a 30 percent reduction in traffic violations over the three- year duration of the program. Traffic safety programs that include highly visible public information and education (PI&E) campaigns that accompany law enforcement efforts have proven to both increase positive public impressions toward police activities and result in safer driving habits. Sail (1983) evaluated the impact of a Selective Traffic Enforcement Program (STEP) initiated in Boise, Idaho, in 1979. The program combined an aggressive traffic enforcement effort with a strong PI&E program in order http://www.ntl.bts.gov/ntl/DOCS/speed/speed.htm 07/19/2000