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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Public Roads - May/June 2016

May/June 2016
Issue No:
Vol. 79 No. 6
Publication Number:
Table of Contents

Communication Product Updates

Communication Product Updates

by Lisa A. Shuler of FHWA's Office of Corporate Research, Technology, and Innovation Management

Below are brief descriptions of communications products recently developed by the Federal Highway Administration’s (FHWA) Office of Research, Development, and Technology. All of the reports are or will soon be available from the National Technical Information Service (NTIS). In some cases, limited copies of the communications products are available from FHWA’s Research and Technology (R&T) Product Distribution Center (PDC).

When ordering from NTIS, include the NTIS publication number (PB number) and the publication title. You also may visit the NTIS Web site at to order publications online. Call NTIS for current prices. For customers outside the United States, Canada, and Mexico, the cost is usually double the listed price. Address requests to:

National Technical Information Service
5301 Shawnee Road
Alexandria, VA 22312
Telephone: 703–605–6000
Toll-free number: 1–888–584–8332
Web site:

Requests for items available from the R&T Product Distribution Center should be addressed to:

R&T Product Distribution Center
Szanca Solutions/FHWA PDC
700 North 3rd Avenue
Altoona, PA 16601
Telephone: 814–239–1160
Fax: 814–239–2156

For more information on R&T communications products available from FHWA, visit FHWA’s Web site at, the FHWA Research Library at (or email, or the National Transportation Library at (or email

Multiple Sources of Safety Information from V2V and V2I: Redundancy, Decision Making, and Trust--Safety Message Design Report (Report)

Publication Number: FHWA-HRT-15-007

dep12_3Vehicles and roadways of the future will employ advanced communications technologies to facilitate applications to make driving safer, more efficient, and more environmentally friendly. Safety benefits will largely be realized by communicating relevant safety information to the driver. This report is part of the Human Factors for Connected Vehicles research program, which aims to minimize driver workload by eliminating connected vehicle device-related distractions. Research described in this document is part of an effort to develop initial design guidance for vehicle-to-infrastructure (V2I) safety messages provided using driver-infrastructure interfaces and driver-vehicle interfaces.

The Human Factors for Connected Vehicles research program is focused on understanding, assessing, planning for, and counteracting the effects of signals or system-generated messages that take a driver’s eyes off the road (visual distraction), the driver’s mind off the driving task (cognitive distraction), and the driver’s hands off the steering wheel (manual distraction). The overall goal of this research is to support the introduction of this technology as a benefit to all transportation users.

The report provides an overview of connected vehicle applications, including definitions of key terms used to describe the architecture of connected vehicle communication and summary descriptions of safety applications. It offers some initial design guidance for V2I safety messages as well as some limited guidance for vehicle-to-vehicle (V2V) systems.

Researchers used existing research on transportation safety and related domains. System designers and State transportation department personnel can use this information to develop and implement V2I applications to ensure these systems work effectively and safely within a larger V2I, V2V, and vehicle-to-device environment.

This document is available to download at

Information as a Source of Distraction (Report)

Publication Number: FHWA-HRT-15-027

This report presents research aimed at advancing the scientific basis for decisions about information displayed within the right-of-way without adversely impacting attention to driving and safety. Researchers conducted six studies and focused on electronic changeable message signs and guide signs on highways.

The first study examined the perceived similarity between messages on a full-color, full-matrix, light-emitting diode electronic display with 0.79-inch (20-millimeter) pixel pitch and the same messages on a liquid crystal display.

The second study examined the legibility distance for text messages on the display used in the first study. Assuming 20/40 vision, researchers determined legibility distance could be estimated using a letter height of 1inch (2.54 centimeters) per 20 feet (6.1 meters) of viewing distance.

In the third study, drivers read the messaging display as they approached it on a closed course that required them to simultaneously navigate a curved path. Researchers examined the effects of electronic message properties such as flashing, phasing, abbreviations, and the use of symbols versus text.

The fourth and fifth studies simulated overhead changeable messages on a freeway with an electronic sign every 0.5 mile (0.8 kilometer). Researchers attempted to distract drivers by displaying highly salient images--faces on brightly colored backgrounds--that changed every 3 seconds. Drivers did not look at the images more often or longer than they looked at text messages related to travel times. None of the signs caused drivers to miss safety-critical messages they encountered later in the drive, and none caused drivers to fail to detect a roadway hazard of spilled logs.

The final study examined the effects of the frequency and spacing of guide signs on navigation performance and eye-glance behavior. This study supported retaining current standards and recommendations for guide signs in the Manual of Uniform Traffic Control Devices.

The document is available to download at

Remotely Monitoring Water Quality Near Highways: A Sustainable Solution (Fact Sheet)

Publication Number: FHWA-HRT-16-018

Collecting data on water quality in streams located near highways can be challenging in remote and difficult-to-reach locations. Obtaining and transporting water samples is time-consuming, expensive, and sometimes dangerous. Another key challenge is that transportation agencies can miss the release of pollutants that occur in a short time period, or the “first flush,” of stormwater runoff from highways.

This fact sheet discusses the Exploratory Advanced Research Program project titled “A Remote, Self-Sustained System for Monitoring Water Quality Near Highways.” The goal of the project was to design a renewable and self-sustaining onsite system. Researchers from Montana State University conducted the study, which was funded by FHWA.

Collecting water quality data is crucial to State departments of transportation in their monitoring efforts to meet permit requirements under the U.S. Environmental Protection Agency’s National Pollutant Discharge Elimination System regulations, particularly during the first flushes of spring stormwater runoff. Placing sensors directly in the water to collect data is an appealing solution, but in situ sensors typically rely on batteries, which require replacement as often as every 3 weeks.

The project involved combining capabilities for remote monitoring of in situ sensors with the generation of renewable and self-sustaining bioenergy. Instead of using batteries, microbial fuel cells power wireless sensors. These fuel cells generate electricity through electrochemical reactions with a type of common and safe bacteria (magnesium oxidizing microorganisms) ubiquitous to streams. Researchers designed the power sources to function as batteries when too little microbial activity occurs in the stream. But when significant microbial activity is taking place, they operate as microbial fuel cells.

This fact sheet presents information about the self-sustained sensing system, field tests, key findings, future work, and the significance of this research to FHWA. The document is available to download at