In Iowa, a CB radio alert system designed to warn truckers of slow moving maintenance vehicles on freeways effectively warned 39 of 59 truckers interviewed that remembered seeing the maintenance work in-progress.

May 2000
Statewide,Iowa,United States

Summary Information

Iowa tested the effectiveness of a Wizard CB radio alert system to warn approaching truckers of slow moving maintenance vehicles on interstate 35 in July of 1999. The test was conducted using a roadway paint crew of four to five vehicles traveling at 25 miles per hour (mi/h) spread out over one mile. The trailing vehicle in the crew was equipped with a CB transmitter to broadcast warning message up to a distance of four miles. The following message was broadcast every 30 to 90 seconds on Channel 19.

"This is an Iowa DOT road work alert. Northbound drivers on Interstate 35, you are approaching a slow-moving paint crew in the right lane. Please use caution."

A survey was conducted at a nearby truck stop for six days to evaluate truckers' reaction to the system. Seventy (70) of the 79 truckers surveyed had their CB radio tuned to Channel 19 during the preceding hours. Fifty-nine (59) of the 70 truckers using Channel 19 saw the paint crew on the side of the road, and out of the 59 that saw the paint crew, 44 heard the warning message. Twenty-four (24) of the truckers said the warning message was the first thing that alerted them of the paint crew, and 39 of the 59 drivers that saw the paint crew said the warning message were effective at warning them of the paint crew.

This study is a part of series of studies caried out for the Midwest Smart Work Deployment Initiative.

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Midwest States Smart Work Zone Deployment Initiative: MwSWZDI Technology Evaluations Year One - Chapter 2: Iowa - Wizard CB Alert System

Author: Maze, T., et al.

Published By: Mid-America Transportation Center,University of Nebraska

Prepared by Iowa State University, The University of Kansas, University of Missouri-Columbia, and the University of Nebraska – Lincoln

Source Date: May 2000



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Benefit ID: 2003-00258