LOW COST SAFETY IMPROVEMENTS · Right Angle *NCHRP 500, Objective Right Angle Crashes 17.1 F2 –...

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LOW COST SAFETY IMPROVEMENTSIMPROVEMENTS

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Introduction

Highway Traffic Fatalities Trend43,220

40,00045,00050,000

25 00030,00035,000

15,00020,00025,000

05,00010,000

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01988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

Introduction

• U.S. Highway System– Fatality Rate has decreased or remained

same (as Traffic is Increasing)B t 42 000 D th & 2 920 000 I j i– But over 42,000 Deaths & 2,920,000 Injuries per Year

• Lane Departure and Intersection CrashesEngineering focus areas– Engineering focus areas

– Rural crashes (70% of fatals)

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Introduction

Rural Road Safety by The Numbers

3.54 Fatality Rate is

2.5 times that for

22.5

32.5 times that for Urban Roads.

40 % of Travel

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1.5 40 % of Travel and 60% of Fatalities

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Local

Minor

Col.

Majo

r Col.

Minor

Art.

Majo

r Art.

Inter

state

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Min

Maj Min

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Introduction

S f t b lSafety – an absolute

“Safer”- a relative term

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Is this road ‘safe’ or ‘unsafe’?

LightingAdvance Warning SignsSigns Delineators Chevrons Chevrons Shoulder Rumble Strip

Which of these low cost measures are required (i e nominal requirement)?

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(i.e., nominal requirement)?

Substantive and Nominal Safety

• Nominal Safety is examined in• Nominal Safety is examined in reference to compliance with standards, warrants, guidelines andstandards, warrants, guidelines and sanctioned design procedures

• Substantive Safety is the actual crash frequency and severity forcrash frequency and severity for highways or roadways

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Nominal Safetyy

Nominal Safety – Advance Warning Sign + Advisory Speed Plaque

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Speed Plaque

Nominal Safetyy1st Step

Speed limit = 45 mph Traffic Volume = 2,000 Traffic Volume 2,000 - Expect 2 crashes per year at this traffic volume

Nominal Safety – Advance Warning Sign + Advisory

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Speed Plaque

Nominal and Substantive Safetyy1st Step 2nd Step

Nominal Safety – Advance Warning Sign + Advisory

Advance Warning Sign + Advisory Speed + Chevrons =

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g g ySpeed Plaque

y“Safer” = Substantive Safety

AASHTO Strategic Safety Plan GuidebooksGuidebooks

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Typical Benefit/Cost Ratios

* From MN DOT TrafficDOT Traffic Safety Fundamentals Handbook

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Handbook

LOW COST SAFETY IMPROVEMENTSIMPROVEMENTS

The Tools –RoadsideRoadside Hazards

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Roadside Hazards

Scope of the Roadside Problemp

About one in three of allthree of all highway fatalities is the result of a single vehicle run-off-the road Crash

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Roadside Hazards

Drivers May Leave the Roadway As A y yResult Of:

Driver Error

Collision Avoidance

Roadway Condition

Vehicle Component FailureVehicle Component Failure

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Roadside Hazards

Driver LimitationsPerceive 2 or more events per second Make 1 to 3 decisions per secondTake 30 to 120 actions per minuteCommit at least one error every 2 minutesAre Involved in a hazardous situation every 2

hoursHave 1 or 2 near collisions per monthHave 1 or 2 near collisions per monthAverage 1 crash every 6 years

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Roadside Hazards

Trees Utility Poles Light Poles Sign Posts Mail Boxes Mail Boxes Steep Ditches Edge Drop Off’s Edge Drop Off s

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Countermeasures for Roadside Hazards:Hazards:

1. Trees – removal & restriction of species2 Utility Poles - relocation2. Utility Poles - relocation3. Sign Supports – breakaway and shielding4. Mail Boxes – crashworthy5. Single-Vehicle Run-Off-the-Road - Rumble g

Strips and Rumble Stripes

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Countermeasures forRoadside Hazards:Hazards:

6. Slopes and Ditches

7. Rumble Strips

8. Rumble Stripesp

9. “Safety Edge”

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Countermeausures for Trees

Proven

CRF = 22%to 71%

*NCHRP 500, Volume 3- Guide for Addressing Collisions

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gwith Trees in Hazardous Locations

Countermeasures for Relocation of Utility PolesUtility Poles

Relocate UtilityRelocate Utility Pole away from edge of pavement

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Reduction in Utility Pole Crashes for Pole Relocationfor Pole Relocation

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Crashworthy Sign Supports

Small signSmall sign Supports –less than 50 Sq Foot

T 1 ½” H lTwo 1 ½” Holes in a 4” x 6” wood post

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wood post

Countermeasures for Street Light PolesPoles

Light Pole within 1 foot of back of curbNon-Breakaway

steel light pole g p

*NCHRP 500, Volume 6, Strategy 15.1 C1 –

8 ft

Strategy 15.1 C1 Improve Roadside Hardware (Light Poles and Sign Posts)

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and Sign Posts)

Countermeasures for Mailboxes

8” h d d8” hardened steel gas pipepipe

*NCHRP 500, Volume 6, Strategy 15.1 B2 –

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gyRemove/Relocate Objects in Hazardous Locations

Update/Replace Roadside HardwareHardware

ReplaceReplace Antiquated Guardrail andGuardrail and Terminals

NCHRP 500, Volume 6, Strategy 15.1 C1 –

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gyImprove Roadside Hardware

Update/Replace Roadside HardwareHardware

NCHRP 350 compliant endcompliant end terminal

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Countermeasures for Slopes

Power pole in toe of ditchD OffDrop- Off

Non-blrecoverable

slope

*NCHRP 500, Volume 6, Strategy 15.1 B1 – Design

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Strategy 15.1 B1 Design Safer Slopes and Ditches

Countermeasures for Slopes

Traversable Sl“After Condition” SlopeAfter Condition

Ditch Filled In

NCHRP 500, Volume 6, Strategy 15.1 B1 – Design

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Strategy 15.1 B1 Design Safer Slopes and Ditches

Countermeasures for Run-Off-the-Road CrashesRoad Crashes

Rumble strips are intended to supplement pavement markingspavement markings Adds sound and vibration to the

visual benefits of painted markings

Provide a drowsy, inattentive, or distracted driver with a cleardistracted driver with a clear warning that the vehicle has left travel lane…

Provides some reaction time before the vehicle leaves the road

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road

Countermeasures for Run-Off-the-Road Crashes – Edgeline Rumble

StripsCRF = 20 to 49% for 2 Lane Tried

NCHRP 500, Volume 6 St t 15 1 A16, Strategy 15.1 A1 –Install Shoulder Rumble Stripsp

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Countermeasures for Run-Off-the-Road Crashes – Centerline

Rumble Strips

Two-Lane Hwy Undivided 4-Lane Hwy1-32

Two-Lane Hwy Undivided 4 Lane Hwy

Rumble Stripes

NCHRP 500, Volume 6, Strategy 15.1 A2 –Install Edge line “Profile marking”

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g

Rumble Stripes

Rumble Stripes on MS 589

Mississippi

NCHRP 500, Volume 6 Strategy 15 1 A26, Strategy 15.1 A2 –Install Edge line “Profile Marking”

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Rumble Stripes

Michigan Michigan initiative with edge line Normal edge line painted over shoulder rumble

Edgeline

Rumble shoulder rumble strip Edgeline

Comparison of painted edgeline in RainNCHRP 500, Volume 6, Strategy 15.1 A2 – Install

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Strategy 15.1 A2 Install Edge line “Profile Marking”

Rumble Stripes

Michigan Michigan initiative with edge line Normal edge line painted over shoulder rumble

Edgeline

shoulder rumble strip.

Michigan I-75Aft 1st Wi t

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- After 1st Winter

Reducing Edge Drop Off Crashes

Example of EdEdge Drop-Off Crash Normal Crash

EdgelineCounty Road

lrecently resurfaced –Edge drop offEdge drop-off resulted in 3 Fatalities

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Fatalities

Reducing Edge Drop-Off Crashes

Normal Edgeline

Edge Drop-off

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Reducing Edge Drop-Off Crashes

Pavement Edge Rutting and Drop-Offs: Edge rutting occurs on all sections of roads Usually a small percentage of road lengthy p g g Caused by errant vehicles in conjunction

with erosionwith erosion Common in curves and near turning

movementsmovements Mailboxes

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Reducing Edge Drop-Off Crashes

“SafetyNormal

“Safety Edge”

EdgelineEdge

NCHRP 500, Volume 6, Strategy 15.1 A8 –Apply Shoulder

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pp y S ou deTreatment

The Safety Edge

Helps errant vehicles to maintain stability particularly on roadway re-entry

Effective up to 5 inches of pavement depth

Beneficial in reducing Tort Liability during t ti & ft j t l ticonstruction & after project completion

NCHRP 500, Volume 6, Strategy 15.1 A8 – Apply Shoulder

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gy pp yTreatment

The Safety Edge

Demonstration Project in Georgia

“Shoe” Installed inInstalled in Screed

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The Safety Edge

Demonstration Project in Georgia

The “Safety Edge”

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Edge

Countermeasures for Roadside HazardsHazards

“Delineate Hazards”Delineate Hazards

*NCHRP 500, SVolume 6, Strategy

15.1 B3 – Delineate Trees or Utility Poles ywith Markers or Retroreflective Tape

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LOW COST SAFETY IMPROVEMENTSIMPROVEMENTS

The Tools –Signing &

Markings &Markings & Lighting

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Signing & Markings & Lightingg g g g g

DiscussionDiscussion

Signs: Markings:g• Warning Signs• Unexpected Hazards

Markings:• Centerline• Edgeline

• Curves• Right of Way Control

• Edgeline• Markers• StopBars

1-46• Regulatory Signs • StopBars

Signing Countermeasures

• Traffic Signs have the 2nd Highest rank• Traffic Signs have the 2nd Highest rank in terms of benefit to cost of all safety countermeasurescountermeasures

39% Fatalities15% Injuries

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Warning Signing

Purpose: …to call attention to unexpected conditions and to it ti th tsituations that

might not be readily apparentreadily apparentto road users

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Warning Signing for Curves

25% of all Highway % g yFatalities occur on Horizontal Curves

NCHRP 500NCHRP 500 Strategy 15.2 Horizontal C

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Curves

Warning Signing for Curves

Case Study: Warning Signs for a CurveSweeping Horizontal Curve with alignment “hidden” by vertical crest

Substantive Safety Record

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eco d

Warning Signing for Curves

Case Study: Warning Signs for a Curve

Tried

CRF = 18%

CRF 22%

CRF = 18%

CRF = 22% with Advisory

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Advisory Speed

Right-of-Way Regulatory Signing

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Right-of-Way Regulatory Signing

Install YIELD or STOP Control T i dInstall YIELD or STOP Control Tried

CRF = 45% 2-Way STOP CRF = 35%

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CRF 45%*Missouri HAL Manual

Right-of-Way Regulatory Signing

Change 2-Way STOP to All-Way STOP

CRF = 53% for all crashesCRF = 84% for Right Angle

*NCHRP 500, Objective

Right Angle Crashes

j17.1 F2 – Provide All-Way Stop Control at Appropriate Intersections

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Appropriate Intersections

Visibility of Right-of-Way Regulatory SigningSigning

(Supplemental Stop Sign in Island)(Supplemental Stop Sign in Island)

*NCHRP 500, Strategy 17 1 E3Strategy 17.1 E3 –Install Splitter Islands on Minor

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Road Approaches

Visibility of Right-of-Way Regulatory SigningRegulatory Signing

(Stop Sign in Island) Three Stop Signs

NCHRP 500, Strategy 17.1 E3 – Install Splitter Islands on Minor Road

CRF = 11% All Crashes

CRF = 36% Right Angle

1-56Approaches

g gCrashes

ObservationTypical layout of intersection guide signs intercepts sight lines from the stop signslines from the stop signs.

SuggestionDevelop/adopt a revisedDevelop/adopt a revised typical layout that relocates all of the signs away from the i t ti

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intersection.

SigningE i i T i l L f T k Hi h G id SiExisting Typical Layout of Trunk Highway Guide Signs

State Trunk Highway

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Highway

Some intersections also contain “Adopt A Highway” signs mixed with intersection guide signs.

SigningR i d T i l L f T k Hi h G id SiRevised Typical Layout of Trunk Highway Guide Signs

6’-8’ off edge of edgelineState Trunk Highway

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Highway

Relocate all “Adopt A Highway” signs that are mixed in with the sequence of guide signs on the approach to intersections.

Markings Countermeasures

2. Markings

A. Centerline and Edge line Warrants

B. Delineation

C Stop Bar PlacementsC. Stop Bar Placements

D. Safety Pylons

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Centerline and Edgeline Markings

Centerline with No-Passing ZonesZones

+ 36%

Tried

Edge lines

(alone) 8%1-61

(alone) 8%

Delineation

TriedTried

Delineation

15% Fatalities6% Injuries

25% - 58%

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Delineation

Traffic Pylons

Close off Area to Channelize Traffic

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Lighting Countermeasures

Lighting has theLighting has the highest benefit to cost ratio of any ofcost ratio of any of the traffic safety countermeasures

Proven

CRF = 18% - 70%for spot locations

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and intersections

Lighting Countermeasures

Pro en• Lighting of rural intersections

Proven

reduced crashes by 25 to 50% - MN study

NCHRP 500 Strategy 17.1 E2 – Improve Visibility by

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gy p y yProviding Lighting

Lighting Countermeasures

Illumination of Rural Curves

Route 376 near Poughkeepsie, NYNY

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Lighting Countermeasures

Illumination of Rural Curves

Cayuga Heights Road just north jof Ithaca, NY

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Low Cost Safety Solutions

Examples of Efficient Low Cost Projects:

District 3 County Road & Trunk Hwy intersectionsRoad Safety AuditsyIntersection improvements

District 6District 6Multi-County horizontal curve projectInstall chevrons at horizontal curves

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Install chevrons at horizontal curves

Low Cost Safety Solutions

SUMMARY

• Data-driven approach• Data-driven approach• Lane Departure• Intersections• Rural safety problem (70% fatals)y ( )• Random location of crashes• Proactive Systematic projects

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• Proactive Systematic projects

Thank You….

D K P EDave Kopacz, P.E.Safety EngineerFHWA – Minnesota Division

(651) 291-6126D id k @fh d t

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David.kopacz@fhwa.dot.gov