The Federal Highway Administration (FHWA) safety goal is to continually improve highway safety. FHWA 

contributes to the U.S. Department of Transportation safety improvement goal; the performance measurements over

the next 10 years for this goal are: (1) a 20 percent reduction in fatalities, (2) a 20 percent reduction in injuries,

and (3) a 50 percent reduction in truck-related fatalities.

The Office of Safety Research and Development (R&D) is making major contributions to help FHWA meet its

performance objectives through activities and accomplishments in the following six priority areas:

September 2004

Interactive Highway Safety Design Model (IHSDM)

IHSDM is a suite of software analysis tools for evaluating safety and

operational effects of geometric design decisions on two-lane rural

highways. IHSDM is available for downloading free of charge at

www.ihsdm.org. The Geometric Design Laboratory within the Office

of Safety R&D provides free technical support to IHSDM users.

Ongoing research and development will enhance and expand the capabilities of IHSDM, in coordination with the Transportation Research

Board’s Highway Safety Manual.

Roadway Visibility Program

The Roadway Visibility Program aims to reduce the number of crashes

where poor visibility is a factor. The program includes evaluations of

headlight technologies and fixed lighting systems to view the roadway

and other road users. Virginia Tech’s Smart Road is being used to 

evaluate pavement markings in wet weather. A separate project on the

Smart Road is intended to develop guidelines for lighting midblock

crosswalks.

Retroreflectivity for Traffic Control Devices

Several studies are underway to establish minimum levels of retroreflectivity for pavement markings and to develop effective methods to

maintain them. The research findings of recent efforts on traffic sign

retroreflectivity has been presented to FHWA’s Safety and Operations

Offices for use in developing guidelines for signs in the Manual on

Uniform Traffic Control Devices (MUTCD).

Simulation and Advanced Computing Research

This cooperative research agreement between FHWA, the National

Highway Traffic Safety Administration, and The George Washington

University relies on finite-element analysis to study crash events.

FHWA uses the research completed through the National Crash

Analysis Center to develop improved roadside safety hardware.

Rollover Crashes

Rollovers occur in approximately one-third of all run-off-road crashes.

This study investigates the causes of rollover crashes using simulation

techniques and crash data collection. Guidelines will be developed to

help practitioners identify site features with high rollover risk, and in

identifying roadway design and other measures for minimizing that risk.

Run-Off-Road

OFFICE OF FFICE OF SAFETY R&D

www.tfhrc.gov

Federal Highway Administration • Turner-Fairbank Highway Research Center

Intersection Improvements

Intersection and intersection-related crashes make up more than 25

percent of all fatal crashes and 50 percent of combined fatal and injury

crashes. The objectives of the Office of Safety R&D are to facilitate

implementation of short-term strategies and to define and evaluate

long-term, higher payoff strategies to improve intersection safety.

Products include Roundabouts: An Informational Guide and Signalized

Intersections: Informational Guide. Ongoing projects are evaluating

novel intersection treatments and configurations, and roundabout

accessibility enhancements.

Surrogate Safety Measures for Intersections

In a recently completed project, FHWA developed, and in an ongoing

project, is validating and implementing intersection safety logic that

can generate surrogate measures of safety from microscopic traffic simulation models. The objective is to enable these models to produce

useful safety measures to complement the current operational measures

used by decisionmakers in intersection design projects.

Intersections
Safety Design and Operation of Shared-Use Path

Intersections with Roadways

This study will identify conflicts between path users and motor vehicles

at the intersections of shared-use paths and roadways. In addition, an

evaluation tool for assessing intersection safety, capacity, and quality of

service will be developed, and guidelines will be outlined for the design

and operation of shared-use path intersections with roadways.

Pedestrian and Bicycle Data

Studies are being conducted to determine the characteristics of nonmotorized road and trail users of tandem bicycles, wheelchairs,

SegwaysTM, and scooters. In addition, methods to automate 

collecting pedestrian and bicycle volumes will be investigated.

Understanding the operating characteristics of these users, and facilitating the data collection of pedestrian and bicycle volumes, will help

improve the design of pedestrian and bicycle facilities and the 

development and evaluation of safety countermeasures.

Pedestrian and Bicycle

Highway Safety Information System (HSIS)

Informed decision making requires an understanding of how safety is

affected by the geometric design of the roadway, the selection and

placement of roadside hardware, the use of traffic control measures,

the size and performance capabilities of the vehicles, and the needs

and abilities of the users. The HSIS is a database that was developed

to meet these needs. The HSIS allows the simultaneous examination

of crash, roadway inventory, and traffic volume data for nine States.

The system has been used to study the safety effects of converting

rural two-lane roadways to four-lane roadways, the relationship of

median width and safety, the safety of lighting options on urban freeways, and many other safety topics.

SafetyAnalyst

A software package with state-of-the-art tools, SafetyAnalyst, is being

developed to correspond to the six main steps in highway safety management: 1) network screening to identify sites and corridors that hold

the most potential for reducing crashes; 2) diagnosis of safety problems

at specific sites; 3) selection of appropriate countermeasures; 

4) economic appraisal of candidate improvements; 5) priority rankings

for candidate improvements; and 6) before-after evaluations of safety

improvement projects.

Digital Highway Measurement Vehicle

Under the Digital Highway Measurement (DHM) project, the

Advanced Research Team is developing an instrumented vehicle and

associated software with increased resolution of measurements at levels

that allows a systematic definition of the roadway geometry as built.

These accurate measurements allow assessment of health conditions of

the road and roadside. This vehicle can collect three dimensional

geometry data of the highway at vehicle speeds of 97 km/h (60 mph)

or less using a high-resolution inertial navigation unit (INU) and high

accuracy differential Global Positioning System (GPS) all in real time.

The vehicle also collects high resolution stereo images, pavement

macro-texture data and lower resolution pavement edge data using a

sweeping laser. Other sensors, such as Ground Penetrating Radar, are

planned to determine the presence and condition of highway infrastructure features. 

Safety-Management

Variable Speed Limits 

Variable speed limits that change automatically with road and traffic

conditions in work zones are being tested in two States as a way to

increase credibility of speed limits, improve safety, and smooth traffic

flow. A companion project with the American Association of State

Highway and Transportation Officials through the National

Cooperative Highway Research Program is addressing legal and

enforcement issues.

Rational Speed Zoning and Enforcement

Demonstration

A series of cooperative tests are being carried out by seven State and

local agencies to demonstrate the extent to which rationally established and strictly enforced speed limits lead to higher compliance

and more effective management of crash risks. A key aspect of these

demonstrations is the coordination of engineering, education,

enforcement, and judicial elements.

Expert System for Speed Zoning

To assist practitioners in establishing appropriate and credible speed

limits for a roadway, an expert system approach is being investigated.

The computer-based expert system, USLIMITS, will provide an

objective, quantifiable, and systematic tool to assist highway agencies

in establishing consistent and safe speed zones. USLIMITS can be

accessed at www.uslimits.com. 

Speed Management

Human Centered Systems Laboratory

The Human Centered Systems Laboratory supports the testing and

evaluation of driver performance with a wide range of testing facilities, which include simulators and an instrumented vehicle. The laboratory performs ongoing research into a wide range of geometric,

traffic control device, and operational issues, as well as the effects of

these elements on drivers and pedestrians. The laboratory allows

researchers to present specific stimuli to participants in a highly controlled environment, thereby incorporating the users’ needs into

FHWA’s R&D program.

Human Centered Systems

FHWA-HRT-04-119

HRTS-01/09-04 (3M)E