Efficacy of Rectangular-shaped Rapid Flash LED Beacons

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An Analysis of the Efficacy of Rectangular-shaped Rapid-Flash LED Beacons to Increase Yielding to Pedestrians Using Crosswalks on Multilane Roadways in the City of St. Petersburg, FL

Dr. Ron Van Houten
&
Dr. J. E. Louis Malenfant

Center for Education and Research in Safety

Table of Contents

Executive Summary

Introduction

Experimental Method

Participants and Setting

Apparatus

Measures

Yielding to Pedestrians

Yielding Distances

Driver Passed or Attempted to Pass Stopped Vehicle

Car Behind Yielding Car Jams on Brakes

Experimental Design

Results

Yielding Right-of-way to Pedestrians

Yielding Distance

Driver Passed or Attempted to Pass Stopped Vehicle

Abrupt Braking

Night Evaluation of Rapid-Flash Devices

Inter-Observer Agreement

Statistical Analysis

Comparison with Overhead and Side-Mounted Beacon

Participants and Setting

Apparatus

Experimental Design

Statistical Analysis

Driver Yielding Behavior

Driver Yielding Distance Behavior

Inter-Observer Agreement

Data for All 18 Sites

Data from Other Sites

Discussion

Determining A Warrant For The Rectangular-Shaped Rapid Flash System

References

Appendix 1

LIST OF FIGURES

FIGURE 1 Images depicting potential cause and screening effect of the multiple threat.

FIGURE 2 Picture of two forward-facing rectangular-shaped LED beacon housing.

FIGURE 3 Photograph of the rectangular-shaped rapid flash LED beacon system's pedestrian activation.

FIGURE 4 Photograph showing flags used for measuring motorists' yielding distance as well as an arrow indicating the dilemma zone as calculated using the ITE signal timing formula.

FIGURE 5 Line graphs showing initial yielding compliances for baseline, treatment conditions, and as a set of one year follow-up collection phases. The graphs represent site locations, in order, 22^nd Ave. N & 5^th St., 1^st St. & 37^th Ave. N, 31^st St. & 54^th Ave. N, and 58^th St. & 3^rd Ave. N.

FIGURE 6 Line graph illustrating nighttime data during initial data collection phases as well as one year follow up for location 1^st. St. & 37^th Ave. N.

FIGURE 7 Photographs showing a traditional over-head circular incandescent flashing beacon (left photograph) and a round side-mounted beacon (right photograph).

FIGURE 8 Set of two bar graphs illustrating the effectiveness of the rectangular-shaped rapid flash LED beacon when compared to either a traditional over-head mounted or side-mounted circular flashing beacon.

FIGURE 9 Bar graph illustrating the effectiveness of the rectangular-shaped rapid flash LED beacon systems in eliciting yielding compliance averaged across sites for a duration up-to and including one year. One site has also been included that was evaluated at a two year interval.

FIGURE 10 Photograph of one of the two installations in Miami Dade County. The device is a median unit shown during activation.

TABLE 1 Table statistical results from two-sample t-test of independent samples.

TABLE 2 Table of descriptive statistical analysis of yielding distances in percentages recorded during each treatment condition averaged across sites.