Can You Read the Signs? · 8 MUTCD Section 2A.09 Minimum Retroreflectivity “Standard: Public...
Transcript of Can You Read the Signs? · 8 MUTCD Section 2A.09 Minimum Retroreflectivity “Standard: Public...
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Can You Read the Signs?
David P. Orr, PESenior Engineer
Cornell Local Roads Program
Sign Standards
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Can You Read the Sign?
Location
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Can You Read the Sign?
Size
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Can You Read the Sign?
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Design & Layout
Can You Read the Sign?
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Brightness
We Need More Light As We Age
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20 33 46 59 72 85Driver's Age
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Sign Standards
LocationSize
Design & LayoutBrightness
Retroreflectivity
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MUTCD Section 2A.09 Minimum Retroreflectivity
“Standard: Public agencies or officials having jurisdiction shall use an assessment or management method that is designed to maintain sign retroreflectivity at or above the minimum levels in Table 2A-3”
The minimum maintained retroreflectivity levels shown in this table are in units of cd/lx/m2
measured at an observation angle of 0.2° and an entrance angle of -4.0°.For text and fine symbol signs measuring at least 1200 mm (48 in) and for all sizes of bold
symbol signsFor text and fine symbol signs measuring less than 1200 mm (48 in)Minimum Sign Contrast Ratio ≥ 3:1 (white retroreflectivity ÷ red retroreflectivity)
* This sheeting type should not be used for this color for this application.
⎯W ≥ 50Black on White
W ≥ 35; R ≥ 7White on Red
Y ≥ 75; O ≥ 75Y*; O*
Y ≥ 50; O ≥ 50Y*; O*Black on Yellow orBlack on Orange
Ground-mountedW ≥ 120; G ≥ 15W*
G ≥ 7
OverheadW ≥ 250; G ≥ 25W*G ≥ 25
W* G ≥ 15
W*G ≥ 7White on
Green
III, IV, VI, VII, VIII, IX, XIIIIIIPrismatic SheetingBeaded Sheeting Additional
Criteria
Sheeting Type (ASTM D4956-04) Sign Color
New MUTCD Table 2A.3Minimum Maintained Retroreflectivity Levels
This font is too small! I can’t read it.
Don’t try to read it! The values are in the
handout.
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ASTM Grade Sheeting
I II III III
VII VIII IX
Prismatic SheetingHi-
IntensitySuper Eng.Engineer
Beaded SheetingColors
New MUTCD Table 2A.3Which Sheeting is Allowable
(Ground Mounted Only)
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Yellow - ASTM Specification
III
III
Prismatic
0
100
200
300
400
500
ASTM Type
cd/lx
/m2
Exempt Signs?Parking/Standing/Stopping
Walking/HitchhikingAdopt-A-Highway
Blue or Brown BackgroundsExclusive Use of Bikes / Ped
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Allowable Methods
Nighttime visual assessmentMeasured retroreflectivity
Expected sign lifeBlanket replacement
Control signs
Nighttime Visual Assessment
Calibration signsConsistent parameters
Comparison panels
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Measured Retroreflectivity
Expected Sign Life
Engineer Grade ~ 7 yearsHi-Intensity ~ 10 years
Prismatic ~ 12 years
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Blanket Replacement
Replace all signs in an area based upon shortest sign life
May have different patternfor different signs
What about damaged signs?
Control Signs
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Combined Methods
Nighttime visual assessmentMeasured retroreflectivity
Expected sign lifeBlanket replacement
Control signs
Future Methods?
Must be based on an engineering study
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New Retroreflectivity Standards
January 2012Establish and implement method
January 2015Replace regulatory, warning, ground-mounted guide signs
(except street name signs)January 2018
Replace street name & overhead guide signs
Cost
Monroe County$1,150,000
Warning and Regulatory Signs665 miles
77,650 s.f.
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Cost
Small Town50 miles
Warning and Regulatory Signs$30,000 for prismatic signs
$2,500 each year
What Now?
InventoryAssessment
Plan
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Coffee Cup Test
Coffee Cup Test
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Coffee Cup Test
Coffee Cup Test
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www.fhwa.dot.gov/retro
Thank you