Figure

1 Related studies illustrating the relationship between accident rate and radius of curvature

2 Intersection geometries examined in the Staplin et al. (1996) field study of right-turn channelization

3 Alternative left-turn treatments for rural and suburban divided highways

4 Left-turn lane offset design values to achieve required sight distances using the modified AASHTO model (J=2.5 s) and unrestricted sight distances

5 The entry process and components of the entry model developed in NCHRP 3-35

6 The exit process and components of the exit model developed in NCHRP 3-35

7 Related studies illustrating the relationship between accident rate and pavement width

8 Optimum distribution of 200- and 300-mm (8- and 12-in) traffic signals

9 Effect of age on sign legibility

10 The effects of day vs. night on sign legibility distances

11 Effect of contrast ratio on legibility

12 Effect of retroreflectivity on legibility

13 Effect of letter series on legibility

14 Effects of letter spacing on legibility

15 Effects of letter height during daylight

16 Effects of letter height at night

17 Confounding number of matrix points with letter height and stroke width

18 Confounding matrix point luminance with size

Table

1 Number of citations obtained and resulting number of articles in final target set for each content area

2 Percent reduction in accidents on horizontal curves with 8-ft beginning lane width as a result of lane widening, paved shoulder widening, and unpaved shoulder widening

3 Expected reduction in number of accidents per intersection per year.

4 Recommended ISD for uncontrolled intersections, based on stopping from a reduced speed

5 Comparison of gap acceptance field study results with results from other studies, based on data for turns from stop-controlled intersections onto a two-lane major road

6 Recommended critical gap value (travel time) for determining sight distance for left and right turns onto the major road at stop-controlled intersections (Cases IIIB and IIIC)

7 Recommended critical gap value (travel time) for determining sight distance for the crossing maneuver at stop-controlled intersections (Cases IIIA)

8 Leg of sight triangle along the minor road for crossing maneuvers from a yield-controlled approach

9 Travel time for a minor-road vehicle to reach, cross, and clear the major road from a yield-controlled approach

10 Recommended travel times for determining sight distance for left and right turns onto the major road at yield-controlled intersections (Case II)

11 Comparison of clearance times obtained in the Staplin et al. (1996) field study with AASHTO Green Book values used in sight distance calculations

12 Required left-turn sight distance to clear one or both opposing lanes

13 Minimum and desirable offsets for opposite left-turn lanes, as a function of opposite left-turn lane vehicle type (passenger car vs truck)

14 Peak (minimum) daytime intensity requirement (cd) for maintained signals with no backplate

15 Optimum distribution of 200- and 300-mm (8- and 12-in) traffic signals

16 Recommended minimum intensity for fully dimmed signals (rounded to nearest 5 candelas)

17 Site characteristics used to assess signal dimming advisability

18 Luminance levels (cd/m²) at which dimming may commence

19 Colors of traffic signals: boundary equations

20 Colors of traffic signals: coordinates of boundary corners

21 Studies used to summarize the effects of specific sign variables on legibility

22 Summary of CMS design elements and key study variables

23 Contrast requirements for edgeline visibility (threshold detection) at 122 m (400 ft) with 5 s preview at a speed of 88 km/h (55 mi/h), as determined by PC DETECT computer model

AAA American Automobile Association

AADT Average Annual Daily Traffic

AAR Association of American Railroads

AARP American Association of Retired Persons

AASHTO American Association of State Highway and Transportation Officials

ADT Average Daily Traffic

ALA American Library Association

ANOVA Analysis of Variance

ANSI American National Standards Institute

ARRB Australian Road Research Board

CIE Commission Internationale De L’Eclairage

CIL Complete Interchange Lighting

CMS Changeable Message Sign

CSF Contrast Sensitivity Function

DCS Dynamic Contrast Sensitivity

DGF Disability Glare Factor

DMQ Decision Making Questionnaire

DSD Decision Sight Distance

DSQ Driving Style Questionnaire

DTR Distance Threshold Recognition

DVA Dynamic Visual Acuity

ES Effect Size

FARS Fatal Accident Reporting System

FHWA Federal Highway Administration

GSA Gap Acceptance (Zone)

HFC Horizontal Foot Candles

HCM Highway Capacity Manual

HSIS Highway Safety Information System

HSRC Highway Safety Research Center

IA Initial Acceleration (Zone)

IES Illuminating Engineering Society

ISBL In Service Brightness Level

ISD Intersection Sight Distance

ITE Institute of Transportation Engineers

ITS Intelligent Transportation Systems

LED Light Emitting Diode

LI Legibility Index

LOS Level of Service

MITS Michigan Information Transfer Source

MOE Measure of Effectiveness

MRVD Minimum Required Visibility Distance

MSC Merge Steering Control (Zone)

MTF Modulation Transfer Function

MUTCD Manual on Uniform Traffic Control Devices

NTIS National Technical Information Service

NTPS National Personal Transportation Survey

PIL Partial Interchange Lighting

PMD Post Mounted Delineator

PRT Perception-Reaction Time

PSD Passing Sight Distance

RCS Relative Contrast Sensitivity

RIDHER Relational Integration of Driver and Highway Engineering Research

ROR Run-Off-The-Road

RPM Raised Pavement Marker

RT Reaction Time

RTOG Right Turn on Green

RTOR Right Turn on Red

RTP Relative Task Performance

RVP Relative Visual Performance

SAE Society of Automotive Engineers

SC Steering Control (Zone)

SCL Speed Change Lane

SIA Specific Intensity per Unit Area

SSD Stopping Sight Distance

STS Symbolic Traffic Signal

STV Small Target Visibility

SVA Static Visual Acuity

TAF Transient Adaptation Factor

TCD Traffic Control Device

TRB Transportation Research Board

TRIS Transportation Research Information Services

TRRL Transport Road Research Laboratory

TVA Transient Visual Adaptation

UFOV Useful Field of View

VC Visual Clear (Zone)

VDL Visibility Distance Level

VL Visibility Level

VTE Visual Task Evaluator