European Best Practices in Vertical Signing Rik Nuyttens 3M Europe 12-13 February 2015 Athens, Greece
Visibility & Safety for Life of the Road Basic Principles Sustainable Innovation Low Cost Measures for High Risk Areas High Accident Road Sections (Black Spots) Rail Road Crossings Construction Workzone Safety Schoolzone Safety
Quick Facts Driving is a highly visual task (some 1 say 90%) Total distance driven at night is 1/3 versus daytime But crashes are about the same day and night fatality rate x 3 during nighttime 2 Lack of visibility at night is a significant challenge for drivers 1. Kline et al, Vision, Aging, and Driving: The Problems of Older Drivers, March 1991, The Journal of Gerontology 2. US Federal Highway Administration, http://safety.fhwa.dot.gov/roadway_dept/retro/gen/back_needs.htm 3. Schnell, T., Yekhshatyan, L., Daiker, R., Konz, J., Effect of Luminance on Information Acquisition Time and Accuracy from Traffic Signs. Paper accepted for presentation and publication, Transportation Research Record, Journal of the Transportation Research Board, 2008. Full report available at http://www.ccad.uiowa.edu/opl/projects/luminance 3M 2007. All Rights Reserved.
Challenges Increasing number of vehicles More kilometers traveled by person Increasing heavy vehicle traffic Congestion in and around cities Pollution
Other challenges Aging population Vulnerable road users (pedestrians / cyclists)
Safe Roadway Design Source: General Overview on Road Safety, Lecture Notes, Dr. Rune Elvik, Institute of Transport Economics, Norway, September, 1999.
Driver Information Needs
How the Technology Works Glass Bead Technology 3M 2007. All Rights Reserved.
Engineer Grade 3M 2007. All Rights Reserved.
3M 2007. All Rights Reserved. How Prismatic Technology Works
Truncated Cube Optics (Non-canted) 3M 2007. All Rights Reserved.
Cone of Returned Light Reflected Light in Divergence Cone Retroreflector 3M 2007. All Rights Reserved. Light Source Direction Most retroreflectors also have diffuse reflection. Diffuse reflected light is simply wasted, as it does not help the nighttime driver. Higher efficiency sheetings divert more light toward the driver.
30% Total Retroreflective Efficiency 30% Total Retroreflective Efficiency Retroreflective Efficiency Minimal retroreflection to larger observation angles All 30% to smaller observation angles 15% to larger observation angles 3M 2007. All Rights Reserved. Only 15% light remains for smaller observation angles All truncated cube corner sheetings have nearly 30% retroreflective efficiency.
3M 2007. All Rights Reserved. Full-Cube technology
Full-Cube Sheeting Retroreflective Efficiency Reflective Sheeting Efficiencies Type XI 60 50 58 % Efficiency 40 30 20 10 8 14 32 Enclosed Bead Encapsulated Bead Truncated Cube Corner Full Cube Corner 0 Reflective Sheeting Efficiencies 3M 2007. All Rights Reserved.
h Where do drivers read signs? Where can we first start reading signs? Legibility index is measure of the reading distance as a function of letter height (with adequate contrast) D/h = 500 (or 5 m/cm of letter height) 1 Do drivers read the signs at 5 m /cm? Not necessarily. Reading occurs in a range, typically around 4 m/cm. Younger people sooner than elder. Motorway signs use 30 cm letter height, to allow enough time. 1. Mace, D. J, Sign Legibility and Conspicuity. In Special Report 218: Transportation in an Aging Society, vol.2, pp. 270-93 2. Schieber, F., Burns, D. M., Myers, J., Willan N., Gilland, J. Driver Eye Fixation and Reading Patterns while Using Highway Signs under Dynamic Nighttime Driving Conditions: Effects of Age, Sign Luminance and Environmental Demand. in TRB 2004 Annual Meeting. 2004. Washington, D.C.: TRB. 3M 2011. All Rights D
+ Sustainable Innovation Prismatic versus glass bead sheeting manufacturing process >95% less VOC >75% less energy >40% less solid waste Higher Mw polymers resulting in more durable sheeting DG³ returns up to 58 % light, means 81% more light than traditional prismatic sheeting Replace illuminated signs Save energy to illuminate the signs Lower infrastructure investment costs Greatly reduces maintenance costs Return on investment : 11 : 1 (praxis : Illinois DOT Hungary Israel Belgium )
BEFORE Lit High Intensity Unlit High Intensity Photos 3M taken 2009. All by Rights Nevada DOT Reserved.
AFTER Action Items: -replaced burned out luminaires on 395 sign -added DG 3 sheeting to Wells Avenue Lit High Intensity Unlit DG 3 3M 2009. All Rights Reserved. Photos taken by Nevada DOT
Full Cubes replace illuminated Signs Hungary Average Illuminated vs DG³ sign : Installation cost : > 100 Electricity cost : > 200 Maintenance cost : > 120 Bulb Changes : > 15 Illuminated sign imparts extra cost of > 400 / sign /year 3M 2008. All Rights Reserved.
Short wavelength light is absorbed by sign. Ordinary Short wavelength light is reemitted as longer wavelength light. Dusk/Dawn Fluorescent Impact Fluorescent 3M 2012. All Rights Reserved.
Advantage of Fluorescent Colours
Black Spots in Hungary Route # 6219 Road section between Mezöfalva and Sárszentmiklos New signs and pavement in March 2001 Additional speed reduction was implemented
Route # 6219 Before After
Route # 6219 Accident Statistics 4 3 2 1 Leath Seriou Slight 0 1997 1998 1999 2000 2001 2002 2003 2004
Romania
Brussels Ring, Forest, Belgium September 2000 Renewal of pavement, pavement marking, barriers and vertical signing
Brussels Ring, Forest, Belgium Injured a/or killed Property Damage # Accidents Mth 1999 2000 Diff. 1999 2000 Diff. 1999 2000 Diff. 8 3 1-2 16 1-15 10 2-17 9 2 0-2 3 1-2 5 1-4 10 6 0-6 5 2-3 11 2-9 11 3 0-3 11 1-10 14 1-13 12 4 0-4 15 2-13 19 2-17 Tot 18 1-17 50 7-43 68 8-60
Black Spots in Croatia Study : Changes of Driver s Environment & Road Traffic Safety (I.Dadic V.Maric) Road Design Planners design it from a bird s eye view Drivers experience it from a worm s eye view Black Spot Assessment from: Point of view of all drivers (incl Trucks, Buses, ) All driving directions & lanes All times of the day All weather conditions May need atypical solutions
Black Spots in Croatia Case Study : Djakovo Bracevci : Road D 515 1989 1997 Curve : Radius : 35 m Av Access Speed : 86,5 km/h Top curve speed : 34,0 km/h Nov 95 :new signs before & in curve Accident Statistics 89 Nov 95 : 119 (no fatal) Nov 95 Oct 97 : 3 (no fatal)
Bulgaria
Construction Work Zone Safety
Studies : ARROWS Gate Effect = announce the upcoming changes in road situation
3M Confidential Norway New regulations since 2006 Better safety in CWZ both day and night Based on Sintef studies Performance aspects : Fluo yellow combinded with red Type 3 reflective material
Studies : PREVENT (2) CWZ Types Long term (>24 uur) Short term - fixed Short term - mobile CWZ lay out : 1. Warning zone 2. Entry zone 3. Transition-In zone (provide safety to workers) 4. CWZ 5. Transition- Out zone 6. Traffic normalisation zone
CWZ : PREVENT
Fluorescent Orange + Type 3 Belgium
Romania : Schoolzone Solution to comply with local authorities & traffic police demands based on driver needs More visible traffic signs Kids protection in school area New traffic sign developed Demo sites
Belgium
Belarus (Minsk)
Schoolzone Safety in Denmark Positive press article : Speed reducer brings speed to 20 30 km/h in front of school. Through-traffic avoids the schoolzone Call for wider use of these speed reducers
Poland : Rail Road Crossings
After
After
Germany
Germany
Germany
European Best Practices in Vertical Signing Rik Nuyttens 3M Europe 12-13 February 2015 Athens, Greece