01337257

Component

This paper reports on a survey that was undertaken in Central Florida between November and December 2009. The primary objectives of the survey were to gain an understanding of the factors affecting drivers’ behavior in adverse visibility conditions, and to examine whether drivers rely on and follow advisory or warning messages displayed on Portable Changeable Message Sign (PCMS) and/or Variable Speed Limit Sign (VSLS) in different visibility, traffic conditions, and at two types of roadways; freeways and two-lane roads. To achieve these goals, several categorical data analysis techniques such as conditional distribution, odds’ ratio, and Chi Square tests were applied. Also, two modeling approaches; Bivariate and Multivariate Probit models were estimated. The results revealed that gender, age, road type, visibility condition, and familiarity with VSLS were the significant factors affecting the likelihood of reducing speed following PCMS/VSLS instructions in inclement visibility conditions. Other objectives of this study were to determine the content of messages that would achieve the best safety and drivers’ compliance and to examine the best way to improve safety during these adverse visibility conditions. The results indicated that “Caution-fog ahead-reduce speed” was perceived as the best message and using PCMS and VSLS together is the best way to improve safety during such inclement weather situations. That is logical as warning drivers about reduced visibility using PCMS should be followed by informing about the safe speed. In addition, based on the survey findings it is recommended to use two successive PCMS prior to Fog/Smoke (FS) zones. This could provide drivers with another chance to read the content of the second PCMS if they missed the first one.

01329018

11-0354

English

20p

2011

Transportation Research Board 90th Annual Meeting

DVD

Figures (2) ; References (27) ; Tables (6)

Behavior; Demographics; Drivers; Fog; Smoke; Surveys; Traffic speed; Variable message signs; Visibility; Warning signs; Weather conditions

Data and Information Technology; Highways; Safety and Human Factors; I71: Traffic Theory; I85: Safety Devices used in Transport Infrastructure

Transportation Research Board Annual Meeting 2011 Paper #11-0354

TRIS, TRB

Feb 17 2011 5:24PM