11-1 LOW COST SAFETY IMPROVEMENTS Practitioner Workshop The Tools – Appendices & References.

11-1

LOW COST SAFETY IMPROVEMENTS

Practitioner Workshop

The Tools – Appendices

& References

11-2

Appendices & References

NCHRP 440 – Accident Mitigation Guide for Rural Congested Hwys

NCHRP 491 – Crash Experience Warrant for Traffic Signals

NCHRP 486 – Systematic Impact of Safety and Traffic Operations Design Decisions

11-3


NCHRP 500 – Volume 5: A Guide for Addressing Unsignalized Intersection Collisions

NCHRP 500 – Volume 3: A Guide for Addressing Collisions with Trees in Hazardous Locations

NCHRP 500 – Volume 6: A Guide for Addressing Run-Off-The-Road Collisions

11-4


TechBrief FHWA-RD-02-103 – Safety Effectiveness of Turn Lanes, 11- 02

FHWA/TX-03/4027-2 Engineering Countermeasures to Reduce Red-Light-Running

NCHRP 470 and US DOT TWG Report – Guidance on TCD’s at Highway-Rail Grade Crossings, 12-3-02

11-5


Numerical Methods of High Crash Location Identification

11-6



11-7



11-8


On-Site Observational Report Form

11-9


On-Site Observational Report – Page 1

11-10


On-Site Observational Report – Page 2

11-11


Road Safety Audit Check List

11-12


Road Safety Audit Check List

11-13


Potential Counter-measures Tables from NCHRP 440

11-14



11-15



11-16



11-17



11-18



11-19

Appendices & ReferencesTable of Crash Reduction Factors

Table of Low Cost Safety Crash Reduction Factors 9/22/2004

Countermeasure Total Crashes Injury CrashesRight Angle

CrashesLeft Turn Crashes

Rear-End Crashes Reference

Roadside Hazards

Removal of Trees 66%

Increase in Distance to Obstacle -Trees

3 ft - 22%; 5 ft - 34%; 8 ft - 49%;

10 ft - 57%; 13 ft - 66%; 15 ft - 71%

NCHRP 440, Table 40 and NCHRP 500Volume 3 & 7

Increase in Distance to Obstacle -Mailboxes, Culverts, and HighwaySigns

3 ft - 14%; 5 ft - 23%; 8 ft - 34%;

10 ft - 40%; 13 ft - NF;

15 ft - NF%NCHRP 440, Table 40 and NCHRP 500Volume 3 & 7

Increase in Distance to Obstacle -Guardrail

3 ft - 36%; 5 ft - 53%; 8 ft - 70%; 10 ft - 78%; 13 ft - NF%;

15 ft - NFNCHRP 440, Table 40 and NCHRP 500Volume 3 & 7

Increase in Distance to Obstacle -Fences and Gates

3 ft - 20%; 5 ft - 30%; 8 ft - 44%;

10 ft - 52%; 13 ft - NF; 15 ft - NF

NCHRP 440, Table 40 and NCHRP 500Volume 3 & 7

Relocation of Utility Poles

11% - 77%; See Table 41, NCHRP

44032% Fatalities;

45% Injuries NCRHP 440, page 67

Flatten side slopes into ditch

6% - 15%; see table in Exhibit V-24, volume 6, NCHRP

500 NCHRP 500, volume 6, Exhibit V-24

Shoulder Edge Line RumbleStrips

20% 49% for 2 ln hwys; 15% - 70%

Interstate NCHRP 440

Rumble Stripes in edge of Lane

11-20


Edge Rumble on shoulders ofRural 4-Lane Highways 24% 53%

McFadden, August 204 ITE AnnualMeeting

Safety Edge (Bevel of outsideedge of Asphalt mat)

Geometric FeaturesInstallation of Left Turn Lane onMajor Road Approaches to RuralIntersection - Three Approaches -Stop Sign 44% one approach

FHWA Tech Brief FHWA-RD-02-103 Nov2002

Installation of Left Turn Lane onMajor Road Approaches to RuralIntersection - Three Approaches -Signal 15% one approach


Installation of Left Turn Lane onMajor Road Approaches to RuralIntersection - Four Approaches -Stop sign

28% one approach; 48% two approaches


Installation of Left Turn Lane onMajor Road Approaches to RuralIntersection - Four Approaches -Signal



Installation of Left Turn Lane onMajor Road Approaches to UrbanIntersection - Three Approaches -Stop Sign 33% one approach


Installation of Left Turn Lane onMajor Road Approaches to UrbanIntersection - Three Approaches -Signal 7% one approach


Installation of Left Turn Lane onMajor Road Approaches to UrbanIntersection - Four Approaches -Stop sign



Installation of Left Turn Lane onMajor Road Approaches to UrbanIntersection - Four Approaches -Signal



11-21


Installation of Right Turn Lane onMajor Road Approaches to Ruraland Urban Intersections - FourApproaches - Stop Sign

14% one approach; 26% both approaches


Installation of Right Turn Lane onMajor Road Approaches to Ruraland Urban Intersections - FourApproaches - Signal

4% one approach; 8% both approaches


Shoulder Widening at RuralIntersections - per foot ofwidening 2.8% per foot NCHRP 500, Strategy 17.1 B10Increase sight distance to ISDvalue per intersection quadrant 5% NCHRP 440Decrease intersection Skew - 3approach intersection - non signalcontrol

AMF = exp(0.00040 skew) NCHRP 486

Decrease intersection Skew - 4approach intersection - non signalcontrol

AMF = exp(0.0054 skew) NCHRP 486

Painted Channelization separatingLeft Turn Lane from Thru Lane

50% rural; 30% suburban; 15% urban NCHRP 500 Strategy 3.1 B 8

Raised Channelization separatingLeft Turn Lane from Thru Lane

60% rural; 65% suburban; 70% urban NCHRP 500 Strategty 3.1 B9

Convert single lane urban stopcontrol intersection to Roundabout 61% 77%

Persaud et al.(2002) evaluated changesin motor-vehicle crashes followingconversion of 24 intersections fromSTOP-controlled or traffic signal-controlled to modern roundabouts in theUSA.

Convert single lane rural stopcontrolled intersection toRoundabout 58% 82%


11-22


Convert multi-lane Urban stopcontrolled intersection toRoundabout 15%


Convert urban signalizedintersection to Roundabout 32% 68%


All Conversions to Roundabout 39% 76%


Warning Signs and Measures

Advance Warning Signs (General) 25% Missouri HAL Manual

Advance Curve Warning Signswith Advisory Speed Plaques 22%

Advance Curve Warning Signswithout Advisory Speed Plaques 18%

Chevron Alignment Warning Signs 33% - 49%NY DOT; Land Transport SafetyAuthority of New Zealand (1996)

Large Arrow Warning Signs fortight turns 43% NY DOT

Advance Intersection WarningSigns - Rural 40% Missouri HAL ManualAdvance Intersection WarningSigns - Urban 30% Missouri HAL Manual

Increase Size of Warning Sign 15%Signalized Intersection Guidebook, Table 106

11-23


Double-Up of Warning Signs(Left+Right Sides of Road) 31% Stan Polaris, Winston Salem NC

Advance Signal Ahead WarningSign 44%

Bonneson, August 2002, EngineeringCountermeasures to Reduce Red LightRunning, Table 6-2, page 6-7.

Advance Signal Ahead WarningSign - rural 16% - 40%

Signalized Intersection Guidebook, Table 104

Advance Signal Ahead WarningSign - urban 16% - 35%

Signalized Intersection Guidebook, Table 104

Warning Flashers with WarningSign 25% - 28%

Missouri HAL Manual +BonnesonAugust 2002

Warning Flashers with Prepare toStop When Flashing tied to signalOperation 73% 35% - 67% NCHRP 440; Bonneson 2002

Advance Transverse RumbleStrips 25% - 35%

Lighting

Intersection LightingFHWA Signalized Intersections: AGuidebook, Table 61

Total Crashes (all hours) 30%FHWA Signalized Intersections: AGuidebook, Table 61

Nighttime Crashes 50% 17% Injury; 43% fatal FHWA Signalized Intersections: AGuidebook, Table 61

Regulatory Signs

Install YIELD Sign Control 45% Missouri HAL Manual

Install 2-Way STOP Control 35% Missouri HAL Manual

Improve visibility of Stop Sign -use Splitter Island 11% 36%

ITE/FHWA Toolbox of Countermeasures,Intersection Briefing Sheet #8, Reference #9; Signalized Intersection Guidebook,

Double-Up of STOP Signs(Left+Right Sides of Road) 30% Stan Polaris, Winston Salem NC

11-24


Change 2-Way Stop to All-WayStop Control 47% - 53% 71% - 84%

NCHRP 500 Volume 5 Strategy 17.1 F2Recent studies (Harwood et al, 2000;and Jorgensen 1978 and Agent & Deen1975) have shown that safety benefitsfrom conversion from 2 to 4-way STOPsare materialized when they arewarranted; After studying urban interse

Overhead Mounted Stop Signs reduces crashes NCHRP 500 Volume 5 Strategy 17.1 E.8Add Stop Beacon to STOPControl (mounted on top of STOPsign) 30% Missouri HAL manual

Add Stop Beacon (MountedOverhead) 43% 45%

NCHRP 440 Effectiveness ofCountermeasures, pp90-94NCHRP 500, Strategy 17.1 E11 Flashing beacons at stop controlled intersections

Lane Use Signing 15%2004 Signalized Intersections: aGuidebook, Table 106

Restrict Parking On IntersectionApproaches 8% - 90%

ITE/FHWA Toolbox of Countermeasures,Intersection Briefing Sheet #8, Reference #1, 7, 11

Provide larger Street Name GuideSigns 15%

ITE/FHWA Toolbox of Countermeasures,Intersection Briefing Sheet #8, Reference #9; Signalized Intersection Guidebook,Table 106

MarkingsMark Centerline (on IntersectionApproaches) 36% NCHRP 440, Page 52Mark Edge Line (on IntersectionApproaches) 8% NCHRP 440, Page 52

Add Centerline and Move StopBar Forward to Extension of CurbLine 29% 24%

ITE/FHWA Toolbox of Countermeasures,Intersection Briefing Sheet #8, Reference #9

11-25


Mark STOP Bar 10% - 25%


Install delineators 25% - 58%15% Fatalities;

6% InjuriesNY DOT; 1996 FHWA Annual Report onHighway Safety Program

Signals

Install New Traffic Signal - 3Approaches 7% 34% 20%

Increase Crashes by

75%Persaud et al (2002), Injury crashreduction is from NCHRP 491 Table 17

Install New Traffic Signal - 4Approaches

Increase total Crashes by 2% 67% 60%

Increase Crashes by

74%Persaud et al (2002), Injury crashreduction from NCHRP 491 Table 17

Upgrade Traffic Signal22% Injuries;38% Fatalities FHWA 1996

Upgrade Traffic Signal Controller 20% - 22%

Bonneson, 2002; ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #1,8, 11

Improve Visibility of Signal Heads -Change Post Mount with MastArm Signals 32% - 49% 44% 74% 41%

ITE/FHWA Toolbox of Countermeasures,Intersection Briefing Sheet #8, Reference #9; FHWA Signalized Intersections: aGuidebook, 2004

Replace 8" Lens with 12" Lens 24% 33% - 47%


Add Backplates to Existing Signal Heads 2% - 24% 7% - 93% 32%

ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #1,9

Install Additional Signal Heads 10% - 15% 42%

ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #9; Signalized Intersections: A

Add Signal Head per Lane 22% 47% ICBC, Polanis, Winston-Salem, NC

Add Supplemental Signal Head 15% 47% - 48% Polanis, Winston-Salem NC

Use "2 Red Indication" SignalHeads 9% - 12% 36% 33%

ITE/FHWA Toolbox of Countermeasures,Intersection Briefing Sheet #8, Reference #9; FHWA Signalized Intersections: aGuidebook, 2004, Table 98

Use Split Phases (Only OneApproach per Phase) 25%

ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #11

11-26


Add Left Turn Phase to anExisting Signal 23% - 48% 63% -70%

ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #1, 6, 12

Add Protected/Permissive LeftTurn Phase to existing Signal 4% - 10% 40% - 64%

ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #1,9

Provide Left Turn Lane+ Left TurnPhase to Existing Signal 35%; 46% - 69% 58%

NCHRP 500 Volume 12, Strategy 17.2A1; Neuman, 1985; FHWA/ITE Toolboxof Countermeasures, Briefing Sheet #8,Reference 12

Provide Left Turn Lane w/o LeftTurn Phase to Existing Signal 15% 46% - 54%

NCHRP 500 Volume 12, Strategy 17.2A1; Neuman, 1985;ITE/FHWA Toolboxof Countermeasures, Briefing Sheet #8,Reference #1

Provide Left Turn Lane + Signalizew/o Left Turn Phase to ExistingSignal 21% - 25% 46% - 54%

NCHRP 500 Volume 12, Strategy 17.2A1; Neuman, 1985;ITE/FHWA Toolboxof Countermeasures, Briefing Sheet #8,Reference #1

Provide Left Turn Lane + Signalize+ Left Turn Phase 25% - 36% 43% - 45%

ITE/FHWA Toolbox of Countermeasures,Briefing Sheet #8, Reference #1

Use Protected Only Left TurnPhase 3% 98%

ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #1,9,10

Optimize Clearance Interval 4% -31% 1% - 30%

Bonneson, 2002; ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #1,9,10

Add All-Red Clearance Interval 25% Bhesania, 1991

Improve Signal Timing (Optimize) 10% - 15%


Coordination of Signals 15% - 17%


Change from Late Night FlashingOperation to normal signaloperation 29% 80%

ITE/FHWA Toolbox ofCountermeasures, 2004, Briefing Sheet#8, Ref #9

11-27


Mn DOT Handbook

11-28


Mn DOT Handbook

11-1 LOW COST SAFETY IMPROVEMENTS Practitioner Workshop The Tools – Appendices & References.

Documents

Transcript of 11-1 LOW COST SAFETY IMPROVEMENTS Practitioner Workshop The Tools – Appendices & References.