Identificación del cliente

Australia

In 1981, G.E. Maisey conducted the first research in Australia to determine the effectiveness of RLR cameras (59). Although this report was not able to be obtained, another research report was able to explain Maisey’s findings (49). Maisey’s research focused on one intersection in Perth, Australia for one year,

beginning in July 1979. South et al. reported Maisey suggested that the RLR camera increased rear-end collisions and reduced right angle collisions (51b). To confirm Maisey’s findings, South et al. performed a second study from 1979 to 1984 and 1984 to 1986 in the city of Melbourne, Australia to evaluate the effectiveness of the RLR cameras (49). South et al.’s research included 46 intersections with cameras and 50 control intersections without cameras. Their results are shown in TABLE 10. As shown, right-angle crashes decreased by as much as 32 percent, while rear-end collisions both increased and decreased. The difference in percentages are due to the definition of the rear-end event. “Rear-end” specifically refers to a vehicle that collides with the rear of another vehicle, while “rear end (turn)” refers to a rear-end collision in which the front vehicle was intending to make a turning movement at the intersection (49).

TABLE 10 Results of Red Light Camera Use in Sydney (49, 51b)

Accident Type Change (%)

Right angle -32.0

Right angle (turn) -25.0 Left against through +2

Rear end -30.8

Rear end (turn) +28.2

Other -2.2

All crashes -6.7

No. of casualties -10.4

In 1993, Hiller et al., along with the New South Whales Road and Traffic Authority, conducted a research study to determine the effectiveness of RLR cameras installed in Sydney, Australia in 1987-1989. The difference between this report and the previously mentioned reports were Hiller et al. selected 16 intersections with cameras and matched them with 16 other control intersections based on crash history. After two-year pre- and post-studies, Hiller et al. concluded the following points about RLR cameras (51a, 49):

• Red light cameras, in general, appeared to reduce right-angle and right- (left-) turn against crashes, and to increase rear-end crashes. The overall crash severity was reduced.

• Red light camera hardware (signposting, signs, and housing for cameras) appeared to be effective at reducing right-angle and right- (left-) turn against crashes, even when seldom used as active sites. • Other suitable countermeasures to the targeted crash types, such as turning lanes, S-lanes, and

additional signal phases, also appear to be as effective as RLR cameras.

• Because “most-used control sites” did not demonstrate any significant reduction, Hiller et al. suggested there might not be any spillover (or halo) effect on RLR crashes at non-camera sites.

As explained in the above Australian research reports, there are a lot of possible holes in the research. However, from the research conducted, conclusions could be drawn upon the reduced crash severity (49).

Great Britain

In 2000, the United Kingdom’s Department for Transport (DfT) created a pilot partnership between cities to evaluate the effectiveness of photo-radar cameras to capture speeding and RLR violators. This

partnership was created with the DfT and the following communities: Cleveland, Essex, Lincolnshire, Northants, Nottingham, South Wales, Thames Valley, and Strathclyde. However, many more communities joined the partnership during the evaluation period and data was added to the four-year evaluation report. In a report for the DfT, the following was concluded after four years of study (60).

• Vehicle speeds were down – Average vehicles speeds at speed camera sites, including red light enforcement cameras, had dropped by around 6 percent, and at new sites there was a 31 percent reduction in speeding. It was concluded that overall drivers traveling 15 mph or more over the speed limit fell 91 percent at permanent camera sites and 36 percent at mobile camera sites.

• Both casualties and deaths were down – After allowing for selection effects (i.e. regression to the mean) there was a 22 percent reduction in personal injury collisions where cameras were introduced. The number of people killed or seriously injured dropped by 42 percent, and 100 fewer fatalities were recorded per year per intersection. Furthermore, 1,745 fewer people were killed, and 4,230 fewer injuries were reported in 2004 alone.

• A cost to benefit ratio of 2.7:1 – A recorded benefit to society in four years was £258 million with a total cost of £96 million for law enforcement.

Another area of Great Britain that has had success in the RLR camera field is Scotland. A study performed by R. Winn in 1993 evaluated Glasgow, Scotland’s RLR system that was installed in 1991. During this time, only warnings were given to violators until 1993. Winn reported in a preliminary 1992 report that RLR was considered the primary cause of 17 percent of all crashes reported at signalized intersections. In the same study, Winn also reported a 69 percent reduction in the total RLR violations, and the violation rate (percentage of the number of violation opportunities) fell from 6.1 to 2.2 percent with the installation of RLR enforcement cameras (49). Winn also published a second questionable follow-up report in 1993 which found there was a 62 percent reduction in the number of injury accidents at six signalized intersections (51o). Although this number seems valid, it was also discovered that Winn showed no indication that six control intersections were used, thus making the report inconclusive (49).

In 1996, Fox conducted a more complete study over three separate periods to investigate Glasgow’s RLR cameras. Three main objectives were outlined in the research, which included the following (37n):

• Determine characteristics and frequency of crashes at pedestrian crossings before and after the camera installation.

• Investigate the impact on all of Glasgow’s signalized intersections with pedestrian crossings of the installation of RLR cameras.

• Examine results of similar regional research to see if any trends may be responsible for observed changes.

The analysis took place between 1989 and 1995. Warnings were only given at the designated intersections (49). Shown in TABLE 11 11 are Fox’s results from the study. The time periods, as shown in

Table 11 are the three designated study periods: (1) Before – January 1989 through June 1991, (2) Interim- July 1991 through March 1993, and (3) After- April 1993 through November 1995.

TABLE 11 Accident Severity at Signalized Junctions by Time Period (Rate per Month) (49, 51n)

Before Interim After Difference %

Fatal per month 0.8 0.5 0.3 -0.5 -67

Serious per month 12.9 8.6 7.8 -5.2 -40

Slight per month 46.3 38.5 33.2 -13.1 -28

Noninjury per month 127.2 109.2 98.8 -28.4 -22

Grand total per month 187.1 156.9 139.9 -47.2 -25

Time Period After-Before Change

Accident Severity

Fox, unlike previous Glasgow researchers, performed a “spillover study,” which looked at four areas of Glasgow. Two of these areas had RLR cameras while the third study area was adjacent to study areas with cameras. The fourth study area was all of Glasgow. Shown in TABLE 12 are the results of Fox’s spillover test

(49, 51n).

TABLE 12 Changes in the Number of Personal Injury Accidents (per Month) at Signalized Junctions by Area of Incidence, Primary Causation, and Time Period (49, 51n)

Before After %Difference Before After %Difference

1 10.9 7.9 -27.6 3.2 2.4 -25.4 53.0 2 0.8 0.4 -51.8 0.3 0.9 -38.9 3.0 3 28.4 19.8 -30.2 3.9 3.1 -21.1 169.0 4 20.0 16.1 -19.5 3.1 2.1 -32.7 143.0 No. of Junctions

ALL PIAs RLR PIAs

Area

Two conclusions were made from the spillover study, as shown in TABLE 12. Fox noticed the -32.7 percent change in personal injury accidents, outside of the areas with the RLR cameras. In the report, Fox concluded that this number “demonstrates that other factors such as junction (intersection) improvements, local traffic management, and increased pedestrian and driver vigilance may have been important in reducing RLR crashes across the whole area [of Glasgow] (51n).” The second conclusion Fox found during this study was a significant reduction in RLR crashes involving professional drivers, such as trucks and taxis (49). An informal conclusion might consider professional drivers more aware of automated enforcement and apply it to their jobs wherever they are working.

Singapore

One of the most congested cities in the world, Singapore has one of the most extensive RLR camera enforcement programs dating back to 1986. It was reported in 1997 by Ng et al. that one in five intersections was enforced by one to three cameras (51h). Ng et al. conducted two research studies a period, of nine years. The first study was to evaluate and review the crash trends for 125 intersections over the period. The results of this study are shown in Figure 20 (49). As shown, there has been a significant decline in annual accident counts per junction after the installation of the red light camera systems in 1986. Ng et al. also notes in the research report that this decline happened even with a 22 percent vehicle growth rate and generally flat crash trends among the signalized intersections (51h).

The second analysis performed by Ng et al. was the evaluation of the before and after change in crash types at 42 signalized intersections with cameras and 42 similar intersections without cameras, but with similar crash rates. The study lasted for two three-year periods, which included before and after data for each three year analysis periods. The results of this analysis are shown in TABLE 13 (51h, 49).

TABLE 13 Crash Rate Change for Camera Enforced Intersections in Singapore (51h)

Type of Crash Before After Change (%)

Angle 1.73 1.43 -1.73

Rear end 0.4 0.4 0

Head on/sideswipe 0.37 0.27 -27

Others 0.47 0.4 -14.9

All crashes 2.97 2.5 -15.8

Although Ng et al. had a strong case in having control sites, research has shown that Ng et al. did not fully account or adjust for possible regression to the mean, because the comparison intersections had different volumes and were located far away from the intersections with cameras (51h).

2.1 2.3 2.45