Minimum Retroreflectivity Levels for Traffic Signs New MUTCD Criteria.

Minimum Retroreflectivity Levels for Traffic Signs

New MUTCD Criteria

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OverviewOverview

Retroreflectivity briefingRetroreflectivity briefing Rule-making effortsRule-making efforts Final Rule summaryFinal Rule summary

Minimum ValuesMinimum Values Require maintenance methodsRequire maintenance methods

future rulemaking future rulemaking Minimum pavement marking levelsMinimum pavement marking levels

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Retroreflection BriefingRetroreflection Briefing

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Retroreflective ElementsRetroreflective Elements

Glass spheres and microsized prisms Glass spheres and microsized prisms are the current technologies used to are the current technologies used to make sign materials retroreflective make sign materials retroreflective

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Cone of RetroreflectionCone of Retroreflection

Retroreflector

Light Source Direction

Reflected light gets dimmer as distance from light axis increases

Reflected light is brighter near light axis

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Nighttime DrivingNighttime Driving

DaytimeDaytime

Many cues Many cues availableavailable

Driver task relatively Driver task relatively easyeasy

NighttimeNighttime

Few cues remainFew cues remainTask more difficultTask more difficult

Retroreflectivity provides nighttime guidanceRetroreflectivity provides nighttime guidance

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Night Travel and CrashesNight Travel and Crashes

0

0.5

1

1.5

2

2.5

3

Fata

litie

s pe

r M

illio

n M

iles

Tra

vel

(200

4 - 20

06)

Nighttime Daytime

Source: National Safety Council

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Retroreflectivity FadesRetroreflectivity Fades

y = -2.0298x + 51.836

R2 = 0.3236

0

10

20

30

40

50

60

70

80

0 2 4 6 8 10 12 14 16

Time (yrs)

Retr

o

(1753)

(695)(654)(1939)

Time (years)

Retr

ore

flecti

vit

y (

cd

/lx/m

2)

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BackgroundBackground

for traffic signs and pavement markings which for traffic signs and pavement markings which apply to all roads open to public travel.” apply to all roads open to public travel.”

of Transportation shall revise the MUTCD to include a standard for a minimum level of retroreflectivity that must be maintained

1993 DOT Appropriations Act – “The Secretary

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Recent FHWA ResearchRecent FHWA Research Overhead guide signs and street name Overhead guide signs and street name

signs signs FHWA-RD-03-082 FHWA-RD-03-082

National sign workshops National sign workshops FHWA-SA-03-002 FHWA-SA-03-002

Updated sign levels Updated sign levels FHWA-RD-03-081 FHWA-RD-03-081

Economic impacts report #2Economic impacts report #2 FHWA-HRT-07-042 FHWA-HRT-07-042

Sign retroreflectivity maintenance Sign retroreflectivity maintenance methodsmethods FHWA-HRT-08-026FHWA-HRT-08-026

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Rule-Making SummaryRule-Making Summary

1985 – Advanced Notice of Proposed 1985 – Advanced Notice of Proposed AmendmentAmendment

1992 - Congressional Directive1992 - Congressional Directive 1998 – AASHTO Resolution to FHWA1998 – AASHTO Resolution to FHWA 2004 – Notice of Proposed Amendment2004 – Notice of Proposed Amendment 2006 – Supplemental Notice of 2006 – Supplemental Notice of

Proposed AmendmentProposed Amendment 2007 - Final Rule2007 - Final Rule

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Final RuleFinal Rule

Published on Dec 21, 2007Published on Dec 21, 2007 Vol 72, No. 245Vol 72, No. 245

Revision #2 of the 2003 Revision #2 of the 2003 Edition of the MUTCDEdition of the MUTCD

Effective Effective Jan 22, 2008Jan 22, 2008

Caltrans has 24 months to adopt as State

regulation in the CA MUTCD by Jan 2, 2010

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Compliance DatesCompliance Dates

Jan 22, Jan 22, 20122012

Identify and begin using Identify and begin using method(s)method(s)

Jan 22, Jan 22, 20152015

Replace identified regulatory, Replace identified regulatory, warning, and ground-mounted warning, and ground-mounted guide signsguide signs

Jan 22, Jan 22, 20182018

Replace identified street name Replace identified street name and overhead guide signsand overhead guide signs

Jan 22, 2010

California MUTCD adoption deadline

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New MUTCD LanguageNew MUTCD LanguageSection 2A.09 Maintaining Minimum Section 2A.09 Maintaining Minimum

RetroreflectivityRetroreflectivity

““Standard: Standard:

Public agencies or officials having Public agencies or officials having jurisdiction shall use an assessment jurisdiction shall use an assessment or management method that is or management method that is designed to maintain sign designed to maintain sign retroreflectivity at or above the retroreflectivity at or above the minimum levels in Table 2A-3”minimum levels in Table 2A-3”

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““Support: Support:

Compliance… is achieved by having a Compliance… is achieved by having a method in place and using the method to method in place and using the method to maintain the minimum levels established maintain the minimum levels established in Table 2A-3. Provided that… a method in Table 2A-3. Provided that… a method is being used, an agency would be in is being used, an agency would be in compliance… even if there are some compliance… even if there are some individual signs that do not meet the… individual signs that do not meet the… levels at a particular point in time.levels at a particular point in time.

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MUTCD Table 2A-3MUTCD Table 2A-3

Sign ColorSign Color CriteriaCriteria

Sheeting Type (ASTM D4956)Sheeting Type (ASTM D4956)

BeadedBeaded PrismaticPrismatic

II IIII IIIIIIIII, IV, VI, III, IV, VI,

VII, VIII, IX, VII, VIII, IX, XX

White on RedWhite on Red CR ≥3CR ≥3 35 / 735 / 7

Black onBlack onOrange orOrange or

YellowYellow

Bold orBold orText Text ≥48”≥48”

xx 5050

Fine orFine orText Text <48”<48”

xx 7575

Black on Black on WhiteWhite 5050

White onWhite onGreenGreen

OverheadOverhead x / 7x / 7 x / 15x / 15 x / 25x / 25 250 / 25250 / 25

ShoulderShoulder x / 7x / 7 120 / 15120 / 15

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Sheeting Types Sheeting Types (ASTM 4956-04)(ASTM 4956-04) That Can Be Used:That Can Be Used:

All prismatic sheeting may be used for all signs.All prismatic sheeting may be used for all signs. High Intensity Beaded (Type III) and Super High Intensity Beaded (Type III) and Super

Engineer Grade (Type II) may be used for all Engineer Grade (Type II) may be used for all signs except for the white legend on overhead signs except for the white legend on overhead guide signs.guide signs.

Engineer Grade (Type I) may be used for all Engineer Grade (Type I) may be used for all signs except for:signs except for:

a. the white legend on guide signs,a. the white legend on guide signs,

b. the white legend on street name signs, and b. the white legend on street name signs, and

c. all warning signs.c. all warning signs.

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Sheeting Types That Can Be Sheeting Types That Can Be Used (cont.)Used (cont.)

Even though a particular type of Even though a particular type of sheeting might initially meet the sheeting might initially meet the minimum retroreflectivity levels when minimum retroreflectivity levels when new, it might quickly degrade to new, it might quickly degrade to below the minimum retroreflectivity below the minimum retroreflectivity levels. levels.

The use of higher performance The use of higher performance sheeting, even though it has a higher sheeting, even though it has a higher initial cost, might provide a better initial cost, might provide a better life-cycle cost for the agency.life-cycle cost for the agency.

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““Guidance: Guidance:

……one or more of the following one or more of the following assessment or management methods assessment or management methods should be used…”should be used…”

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Sign Maintenance Sign Maintenance MethodsMethods

Visual nighttime inspectionVisual nighttime inspection Measured sign retroreflectivityMeasured sign retroreflectivity Expected sign lifeExpected sign life Blanket replacementBlanket replacement Control signsControl signs Any combination of aboveAny combination of above Other methods based on Other methods based on

engineering studiesengineering studies

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Visual Inspection Visual Inspection MethodMethod

NighttimeNighttime visual inspection by visual inspection by inspector trained on the procedures inspector trained on the procedures and the ruleand the rule

Conduct on regular basis Conduct on regular basis Must use one of the options:Must use one of the options:

Calibration signsCalibration signs Consistent parametersConsistent parameters Comparison panelsComparison panels

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Calibration Signs OptionCalibration Signs Option ““Calibrate” eyes with calibration Calibrate” eyes with calibration

signssigns Calibration Calibration

signs are near signs are near minimum retrominimum retro

Evaluate signs Evaluate signs compared to compared to calibration signscalibration signs

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Consistent Parameters Consistent Parameters OptionOption

Inspection process replicates criteria Inspection process replicates criteria used to develop minimum levelsused to develop minimum levels Inspector – older driver (>60 years)Inspector – older driver (>60 years) SUV type vehicleSUV type vehicle Cutoff headlamps (properly aimed)Cutoff headlamps (properly aimed)

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Comparison Panels Comparison Panels OptionOption

Small panels at/near minimum Small panels at/near minimum retroreflectivity levelsretroreflectivity levels

Clipped to sign - viewed from distanceClipped to sign - viewed from distance Replace sign if panel is brighterReplace sign if panel is brighter

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Compare average to Compare average to minimumminimum

Not all signs need to Not all signs need to be measuredbe measured Measure marginal Measure marginal

signssigns

Measured Measured Retroreflectivity MethodRetroreflectivity Method

Measure signs with Measure signs with retroreflectometerretroreflectometer

Procedure in ASTM E1709Procedure in ASTM E1709 Average of 4 measurementsAverage of 4 measurements

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HandheldHandheldDevicesDevices

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Expected Sign Life Expected Sign Life MethodMethod

Determine expected life of sheeting types Determine expected life of sheeting types used in geographical areaused in geographical area

End of life based on retro values in End of life based on retro values in supplemental documentsupplemental document

Set up replacement program that ensures Set up replacement program that ensures individual signs are replaced prior to the individual signs are replaced prior to the end of service life expectancyend of service life expectancy

Periodic nighttime or instrument Periodic nighttime or instrument inspections to verifyinspections to verify

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Indicating Sign AgeIndicating Sign Age

Stickers on front or back of sign to Stickers on front or back of sign to show when fabricated or installedshow when fabricated or installed

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Blanket Replacement Blanket Replacement MethodMethod

Divide agency into areas/corridorsDivide agency into areas/corridors Relate number of areas to replacement Relate number of areas to replacement

cycle (based on service life)cycle (based on service life) Replace all signs in Replace all signs in

an area/ corridor an area/ corridor each replacement each replacement cyclecycle 10 yr life, 10 yr life, 10 areas 10 areas Annual replacement Annual replacement

in each areain each area

Replace Replace all signs all signs in this in this area area

during during 1st year1st year

Replace Replace all signs all signs in this in this area area

during during 3rd year3rd year

5th5thyearyear

7th7thyearyear

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Control Signs MethodControl Signs Method

Select signs to represent all signs in the Select signs to represent all signs in the fieldfield Control signs in maintenance yardControl signs in maintenance yard Selected field signs (near HQ)Selected field signs (near HQ)

Monitor control signsMonitor control signs Replace all equivalent signs when control Replace all equivalent signs when control

signs near minimum levelssigns near minimum levels Other methods determine replacementOther methods determine replacement

Control signs need to adequately Control signs need to adequately represent all signs in the fieldrepresent all signs in the field

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Combining AlternativesCombining Alternatives

Combination of methodsCombination of methods Use one or more of the methods Use one or more of the methods

togethertogether Support and reinforce each otherSupport and reinforce each other

PossibilitiesPossibilities Visual inspection to identify signs to be Visual inspection to identify signs to be

measuredmeasured Measured retro of control signsMeasured retro of control signs

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MUTCD LanguageMUTCD Language

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Value of Value of InspectionInspectionInspectors Inspectors can identify can identify deficient deficient signs that signs that may not meet may not meet the minimum the minimum retroreflectiviretroreflectivity levelsty levels

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Agencies use computers to manage Agencies use computers to manage processprocess Track many elementsTrack many elements Help plan and budgetHelp plan and budget

Computers track:Computers track: Sign type & sheetingSign type & sheeting LocationLocation Installation dateInstallation date Expected sign lifeExpected sign life Other factorsOther factors

Computer Sign ManagementComputer Sign Management

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Pavement Marking Pavement Marking Retroreflectivity Retroreflectivity

StandardsStandards- Status - - Status -

Initial research conducted in 1990sInitial research conducted in 1990s Recent research just completedRecent research just completed Impacts report just completedImpacts report just completed Workshops completed in summer 2007Workshops completed in summer 2007

Input from public agencies Input from public agencies AASHTO & ATSSA submitted AASHTO & ATSSA submitted

recommendationsrecommendations FHWA beginning work on NPAFHWA beginning work on NPA

no target dateno target date

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Keep In MindKeep In Mind

Congressional directive applies to Congressional directive applies to signs and markings signs and markings

FHWA will establish MUTCD FHWA will establish MUTCD standards for pavement markingsstandards for pavement markings Solicited agency input for pavement Solicited agency input for pavement

markings in summer 2007markings in summer 2007 Looking for solutionsLooking for solutions Win-Win-Win for Drivers-Agencies-Win-Win-Win for Drivers-Agencies-

FHWAFHWA

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FHWA Supporting FHWA Supporting MaterialMaterial

FHWA Retro Web FHWA Retro Web SiteSite

4-page summary4-page summary

FAQsFAQs

Research ReportsResearch Reports

www.fhwa.dot.gov/retrowww.fhwa.dot.gov/retro

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Sign Sheeting ID GuideSign Sheeting ID Guide

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SummarySummary

New regulation in placeNew regulation in place Must use an assessment or Must use an assessment or

management method in MUTCDmanagement method in MUTCD Must begin to make decisions now in Must begin to make decisions now in

order to meet compliance datesorder to meet compliance dates Consider life-cycle costs, not just initial Consider life-cycle costs, not just initial

costs, when replacing signscosts, when replacing signs

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Additional InformationAdditional Information More information about sign and marking More information about sign and marking

retroreflectivity can be found atretroreflectivity can be found at FHWA: www.fhwa.dot.gov/retro FHWA: www.fhwa.dot.gov/retro ATSSA: www.retroreflectivity.netATSSA: www.retroreflectivity.net

Expert Contact InformationExpert Contact Information FHWA Retroreflectivity Team LeaderFHWA Retroreflectivity Team Leader

Greg Schertz, 720-963-3764Greg Schertz, 720-963-3764 FHWA Research OfficeFHWA Research Office

Carl Andersen, 202-493-3366Carl Andersen, 202-493-3366 FHWA Safety OfficeFHWA Safety Office

Matt Lupes, Matt Lupes, 202-366-6994202-366-6994

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Discussion / Questions

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Some Common QuestionsSome Common Questions

What about..What about.. Engineering grade sheeting ?Engineering grade sheeting ? Fluorescent signs ?Fluorescent signs ? Blue and brown signs ?Blue and brown signs ?

See FHWA FAQs for more questions:See FHWA FAQs for more questions:

www.fhwa.dot.gov/retrowww.fhwa.dot.gov/retro

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Can I use Eng Grade Can I use Eng Grade Shtg?Shtg?

Yes, but not for all signsYes, but not for all signs

Where Engineering Grade cannot be Where Engineering Grade cannot be used:used: Yellow and orange signsYellow and orange signs Legends on guide signs Legends on guide signs

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Fluorescent SignsFluorescent Signs

Fluorescent versions of sign colors Fluorescent versions of sign colors may be used. Minimum retro is may be used. Minimum retro is same as for non-fluorescent same as for non-fluorescent versions.versions.

fluorescent yellow &fluorescent yellow &

fluorescent yellow-greenfluorescent yellow-green Use retro values for yellowUse retro values for yellow

fluorescent orangefluorescent orange Use retro values for orangeUse retro values for orange

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Blue & Brown SignsBlue & Brown Signs

Not yet included in minimum levelsNot yet included in minimum levels Pending report contains Pending report contains

recommended blue and brown levelsrecommended blue and brown levels FHWA-HRT-08-029FHWA-HRT-08-029

Minimum Retroreflectivity Levels for Traffic Signs New MUTCD Criteria.

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