euro road lighting

7/28/2019 Euro Road Lighting

1/83

International Technology Exchange Program

S E P T E M B E R 2 0 0


2/83

NOTICE

The contents of this report reflect the views of the authors, who are responsible for the factsand accuracy of the data presented herein. The contents do not necessarily reflect the officialpolicy of the Department of Transportation.

The metric units reported are those used in common practice by the persons interviewed.

They have not been converted to pure SI units because in some cases, the level of precisionimplied would have been changed.

The United States Government does not endorse products or manufacturers. Trademarks ormanufacturers names appear herein only because they are considered essential to thedocument.

The publication of this document was sponsored by the U.S. Federal Highway Administration

under contract number DTFH61-99-C00005. awarded to American Trade Initiatives, Inc. Anyopinions, options, findings, conclusions, or recommendations expressed herein are those ofthe authors and do not necessarily reflect those of the U.S. Government, the authors parentinstitutions, or American Trade Initiatives, Inc.

This report does not constitute a standard, specification, or regulation.


3/83

Technical Report Documentation Page

1. Report No.

FHWA-PL-01-0342. Government Accession No. 3. Recipients Catalog No.

4. Title and Subtitle

European Road Lighting Technologies5. Report Date

September 20016. Performing Organization Code

7. Author(s) Dale Wilken, Balu Ananthanarayanan, Patrick Hasson, Paul J.

Lutkevich, C. Paul Watson, Karl Burkett, John Arens, Jim Havard, Jeff

Unick

8. Performing Organization Report No.

9. Performing Organization Name and Address

American Trade Initiatives

P.O. Box 8228

Alexandria, VA 22306-8228

10. Work Unit No.(TRAIS)

11. Contract or Grant No.

DTFH61-99-C-0005

12. Sponsoring Agency Name and Address

Office of International Programs

Office of Policy

Federal Highway Administration

U.S. Department of Transportation

13. Type of Report and Period Covered

14. Sponsoring Agency Code

15. Supplementary Notes

FHWA COTR: Donald W. Symmes, Office of International Programs

16. AbstractThe objective of this scanning tour was to gather information from European transportation ministries and

lighting professionals regarding cutting-edge research and technologies in highway and roadway lighting

systems, including tunnel illumination, sign lighting, and all methods used to design roadway lighting systems.

Some of the information could provide a basis on which to update the American Association of State Highway

and Transportation OfficialsInformational Guide for Roadway Lighting.

In April 2000 the scan team visited Finland, Switzerland, France, Belgium, and the Netherlands. Based on its

observations, the panel developed specific recommendations for the U.S. lighting community in such areas as

visibility design technique; dynamic road lighting; pavement reflection factors; master lighting plans; lighting

techniques for roundabouts, crosswalks, and pedestrian areas; energy-absorbing poles; signs; and equipment

quality level and maintenance.

17. Key WordsLuminance, small target visibility, luminaire, counter-

beam, pro-beam, reflectance.

18. Distribution Statement

No restrictions. This document is available to the public

from the

Office of International Programs

FHWA-HPIP, Room 3325

US Dept. of Transportation

Washington, DC 20590

[email protected]

www.international.fhwa.dot.gov19. Security Classif. (of this report)

Unclassified20. Security Classif. (of this page)

Unclassified21. No. of Pages

8022. Price

Free

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized


4/83


5/83

i

Eur opean RoadLight ing Technol ogies

Pr epar ed by t he st udy t our t eam

a nd

Am erican Trad e Initiatives, Inc.

&

Avalon Integrated Services, Inc.

for the

Federa l Highw ay Ad m inistrat ionU.S. Dep a rtm en t of Tra nsp orta tion

a nd

The A m erican Associat ion of State H ighw ay a ndTran sp orta tion Officia ls

a nd

The Na tional Coop erat ive Highw ay Research Program(Pan el 20- 36 )

of the Tra nsp ortation Resea rch Boa rd

Sep tem b er 20 01

Dale Wilken

FHWA

Balu Ananthanarayanan

Wisconsin DOT

Patrick HassonFHWA

Paul J. Lutkevich

Parsons Brinckerhoff

C. Paul Watson

Alabama DOT

Karl BurkettTexas DO T

John Arens

FHWA

Jim Havard

LITES

Jeff UnickPennsylvania DOT


6/83

ii

FHWA INTERNATIONAL TECHNOLOGY

EXCHANGE PROGRAMS

The FHWAs international programs focus on meeting the growing demands of its

par tners a t t he Federa l, Sta te, and local levels for a ccess to informa tion on st a te-of-

the-art technology and the best practices used worldwide. While the FHWA is

considered a world leader in highway transportation, the domestic highway

commun ity is very int erested in t he a dva nced t echnologies being developed by othercountr ies, a s well as innovative orga niza tional a nd finan cing techniques used by the

FHWAs international counterparts.

INTERNATIONAL TECHNOLOGY SCANNING PROGRAM

The In terna tional Technology S canning P rogram a ccesses a nd eva luat es foreign

technologies and innovations th a t could significa ntly benefit U.S. highwa y

tr a nsporta tion syst ems. Access to foreign innova tions is str engthened by U.S.

participation in the technical committees of international highway organizations and

thr ough bila tera l technica l excha nge a greements w ith selected na tions. The progra m

ha s underta ken cooperat ives with t he American Associa tion of St a te H ighwa yTra nsport a tion Officia ls an d its S elect Committ ee on I ntern a tional Activities, a nd t he

Transportation Research Boards National Highway Research Cooperative Program

(P a nel 20-36), th e priva te sector, an d a cadem ia .

P riority t opic a reas a re jointly det ermined by t he FH WA a nd its par tners. Team s of

specialists in t he specific a rea s of expertise being investiga ted a re formed a nd sent t o

countr ies where significa nt a dva nces a nd innovat ions ha ve been ma de in technology,

ma na gement pra ctices, orga niza tional str ucture, progra m delivery, a nd fina ncing.

Teams u sua lly include Federal a nd S ta te highw ay officials, priva te sector a nd

industr y a ssocia tion representa tives, a s w ell as members of the a cademic commun ity.

The FH WA ha s organ ized more th a n 40 of these reviews a nd dissemina ted resultsna tionw ide. Topics have encompassed pa vement s, bridg e constr uction a nd

ma intenance, contra ct ing, intermoda l t ra nsport , organizat ional ma na gement, w inter

road ma intena nce, safety, intelligent tra nsport a tion systems, pla nning, an d policy.

Findings a re recommended for follow-up w ith furth er resear ch a nd pilot or

demonstration projects to verify adaptability to the United States. Information about

the scan findings and results of pilot programs are then disseminated nationally to

St at e a nd local highway tra nsporta t ion officials a nd t he privat e sector for

implementation.

This progra m ha s resulted in significant improvements a nd sa vings in road program

technologies a nd pra ctices throughout t he Unit ed Sta tes, part icular ly in the ar eas ofstru ctures, pavements, sa fety, a nd w inter road ma intena nce. J oint r esea rch and

technology-sha ring projects h a ve also been la unched with interna tional count erpart s,

furth er conserving resources a nd a dva ncing the stat e of the ar t.

For a complete list of In ter na tiona l Technology Sca nnin g topics, and to order fr ee

copies of th e report s, please see list on th e facing pa ge.

Website: ww w.interna tional.fhwa .dot.gov

Email: [email protected]


7/83

iii

FHWFHWFHWFHWFHWA INTERNAA INTERNAA INTERNAA INTERNAA INTERNATIONAL TECHNOLOGY EXCHANGE REPORTSTIONAL TECHNOLOGY EXCHANGE REPORTSTIONAL TECHNOLOGY EXCHANGE REPORTSTIONAL TECHNOLOGY EXCHANGE REPORTSTIONAL TECHNOLOGY EXCHANGE REPORTS

Infrastructure

G eotechnical Engineering P ract ices in Ca nada and Europe&G eotech nology S oil Na ilin g &Int ernat iona l Contra ct Administra tion Techniques for Quality E nha ncement-CATQEST&

Pavements

E uropean Aspha lt Technology&&E ur opea n C oncrete Technology&&Sout h Africa n P av ement TechnologyH ighw a y/Commercia l Vehicle In tera ctionRecycled Materials in European Highway Environments&

Bridges

European B ridge StructuresAsian Bridge StructuresB ridge Maintenance Coat ingsEuropean Practices for Bridge Scour and Stream Instability CountermeasuresAdva nced Composites in Bridges in Europe a nd J a pan&St eel B ridge Fabricat ion Technologies in Eur ope a nd J a pan&

Performan ce of Concrete Segmenta l an d Ca ble-St a yed B ridges in Europe&

Planning and Environment

Eur opea n I ntermoda l P rograms: P lan ning, P olicy a nd Technology&Na tional Tra vel Surveys&Recycled Materials in European Highway Environments&G eometric Design Pr a ctices for E uropean R oads&

Safety

Pedestr ian a nd B icycle Safety in England, G ermany a nd the Netherlands&Speed Ma na gement a nd E nforcement Technology: Europe & Aust ra lia&Sa fety Ma nagement P ract ices in J apa n, Austra lia , and New Zeala nd&Roa d S a fety Audits Fin a l R eport &Roa d S a fety Audit sCa se St udi es &In novat ive Tra ffic Contr ol Technology & P ra ctice in E urope&Commercia l Vehicle Sa fety Technology & P ra ctice in E urope&Methods a nd P rocedures to Reduce Motorist Dela ys in E uropean Work Zones&

Operat ions

Adva nced Tra nsporta tion Technology&European Traffic MonitoringTra ffic Man a gement a nd Tra veler Informat ion Sy stemsE ur opea n Wint er S ervice TechnologySnowbreak Forest Book Highway Snowstorm Countermeasure Manual (Translatedfr om J apanese)E uropean Road Light ing Technologies&

Policy & Inform ation

Em erging Models for D elivering Tra nsporta tion P rograms a nd S ervicesAcquiring H ighwa y Tra nsporta tion Informa tion from AbroadHan dbook&Acquiring H ighwa y Tra nsporta tion Informa tion from AbroadFina l Report&Internat ional G uide to Highwa y Transporta t ion Informa tion&

&Also available on the internet

&&Only on the internet a t www.international.fhwa.dot.gov


8/83


9/83

CONTENTS

v

HIGH-MAST, DECORATIVE, AND SIGN LIGHTING.......................................................30

H igh-Ma st Light ing ......................................................................................................... 30

Decorat ive Ligh tin g ......................................................................................................... 30

Sig n Ligh tin g ................................................................................................................... 30

P a nel Recomm enda tion ................................................................................................... 33

ROUNDABOUTS.........................................................................................................34Rounda bout Ca tegories ................................................................................................... 34

Lum ina ire Loca tions ....................................................................................................... 34

Rounda bout Light L evels ................................................................................................ 35

P a nel Recommenda tion ................................................................................................... 35

SAFETY IMPLICATIONS................................................................................................36

Oth er Observa tions ......................................................................................................... 38

P a nel Recomm enda tion ................................................................................................... 39

FUTURE DEVELOPMENTS............................................................................................40

New Eu ropean St a nda rds ............................................................................................... 40Tra ffic Contr ol Center s ................................................................................................... 40

Dy na mic Road wa y Ligh tin g ............................................................................................ 41

G uida nce Sy stem s ........................................................................................................... 42

P avem ent Reflection Qua lities ....................................................................................... 43

Tunn els ............................................................................................................................. 44

Resea rch Needs ................................................................................................................ 45

Overa ll Resea rch Im pressions ........................................................................................ 45

P a nel Recomm enda tions ................................................................................................. 45

SUMMARY OF RESEARCH RECOMMENDATIONS.......................................................46

ACKNOWLEDGMENTS................................................................................................47

APPENDIX A: PANEL MEMBERS.................................................................................48

APPENDIX B: AMPLIFYING QUESTIONS....................................................................53

APPENDIX C: KEY CONTACTS IN HOST COUNTRIES.................................................60

APPENDIX D: KEY PAPERS.........................................................................................64

APPENDIX E: OUTREACH ACTIVITIES IN 2000...........................................................65

ENDNOTES..................................................................................................................66

TABLES

1. Schedule of Team Meetings ........................................................................................ 3

2. Scan Team It inerar y ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 3

3. R-Ta ble Va lues, by Pa vement Cla ss .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 20

4. Fata lities in Road Accidents .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 36

5. Fata lities per 1 billion vehicle kilometers t ra veled ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 37


10/83

CONTENTS

vi

FIGURES

1. The roadw ay lighting sca n tea m ..... . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 2

2. Maintena nce of luminaires, Sw itzerland . . .. . .. . .. . .. . .. . .. . .. . .. .. . .. . .. . .. . .. . .. . .. . .. . .. .. . .. . .. . .. . . 7

3. Tunnel cleaning in Pa ris .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 8

4. & 5. Ma ster light ing pla ns, Pa ris .................................................................................. 9

6. Results of crash test of energy-a bsorbing pole... . . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 9

7. & 8. Result s of R-Techs stu dy on ligh t pollution ....................................................... 109. U niform vs. nonuniform lighting ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 15

10. Typica l t hree-dimensiona l ta rget .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 15

11. Model r oa dwa y insta llat ion ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 16

12. View of Lecocqs computer modeling softwa re ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 16

13a. Demonstra t ion roadw ay w ith 3-D spheres and squa re, f lat ta rgets . . .. .. . .. . .. . .. . .. . 17

13b. P hotogra phic ima ge (zoom) of ta rgets .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 17

13c. Syn thesized ima ge of ta rgets .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 17

14. Syn thesized configura tion of roa d surface ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 18

15. Syn thesized configura tion of roa d surface ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 18

16. Lighting scheme for crosswalks, Sw itzerla nd ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . .. . . .. . . .. . . .. . 18

17. Wevelgem Tunn el, B elgium .................................................................................... 1918. Highw ay near Helsinki Airport, Finla nd ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 19

19. Highw ay s nea r Helsinki, Finlan d ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 19

20. Milchbuck Tunnel, Sw itzerla nd ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 21

21. New porous a sphalt .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 21

22. Porous a sphalt , after 12 month s ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 22

23. Wet roadw ay in Finlan d ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 22

24. U nderground roundabout, Sw itzerla nd ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 24

25. Underground roundabout entra nce and exit feeds to

und erground pa rking ............................................................................................. 24

26. Tunnel in Lyon, Fra nce ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 25

27. Tunnel in Helsinki, Finla nd ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 25

28. Tunnel at Schipol Airport , the Netherla nds ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 26


30. Wevelgem Tunn el, B elgium .................................................................................... 26


32. B lack Window method, the Netherla nds ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . .. . . .. . . .. . 27

33. Exa mples of B lack Windows ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 27

34a . Sy mmetr ica l (bisymmetrical) light dist ribution ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 28

34b. Count er-beam light dist ribut ion ............................................................................ 28

34c. P ro-beam light dist ribut ion .................................................................................... 28

35. High-ma st lighting, Finland ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 30

36. High-ma st lighting, B elgium.... . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 30

37. Pa rking lot lighting, Helsinki, Finlan d ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 31

38. Pa rking lot lighting, Helsinki Airport , Finla nd ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 31

39. To aid recognit ion, vert ical a nd semispherica l il luminance is

used in pedestria n a rea s ........................................................................................ 31

40a ., b. & c. Exa mple of typical decora tive lighting in Zurich, Sw itzerla nd ... .. . . .. . . .. . . 32

41. & 42. Dow nt own Helsinki, Finla nd ......................................................................... 32

43. & 44. Decorat ive lighting in Fin la nd ....................................................................... 33

45. & 46. Zurich, Sw itzer la nd, at nig ht ......................................................................... 33


11/83

CONTENTS

vii

47. Micro-prismat ic sheeting ma teria ls for signs in Finla nd ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 33

48. Roundabout, P a ris, Fra nce ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 34

49. Roundabout at P hilips Outdoor Lighting Applicat ion Center,

La Va lbonne, Fra nce ............................................................................................... 34

50. Sw iss recommendat ion for lumina ire placement .. . .. . . .. . . .. . . . .. . . .. . . .. . . .. . . .. . . .. . . . .. . . .. . . 35

51. The Sw iss Vision Zero progra m ..... . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 38

52. Road accidents compa red wit h numbers of vehicles .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 3953. & 54. Views of a TCC in S w itzer la nd (left) and F inla nd (right ) ............................. 40

55. Low level of roadw ay lighting, the Netherla nds ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 41

56. Norma l level of roa dwa y lighting ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . 41

57. High level of roa dwa y light ing ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 41

58. Dut ch guida nce systems under investigat ion ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 42

59a . & b. In -roa d, fiber-optic delinea tors ........................................................................ 43

60. Exa mples of colored pavement ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 43

61. & 62. Applica tion of colored pa vement .................................................................... 44

63. Typica l m otorists view of a tun nel .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . . 44

64. Virtua l reflectometer, Fra nce ... .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. 45

65. Effects of t unnel lighting color .. . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . .. . . 45


12/83

viii

OVERVIEW

The volume of vehicle tra ffic is increa sing w orldw ide, a nd r oadwa y lighting can be a n

effective t ool to help provide efficient a nd sa fe tr a ffic movement . The U.S.

tr a nsporta tion community is interested in identifying cutt ing-edge resea rch and

technologies in highwa y a nd roa dwa y lighting systems. Specific interests include

tun nel illumina tion, sign lighting, a nd visibility m etrics tha t a re used in the design of

roadway lighting systems.

The American Association of State Highway and Transportation Officials (AASHTO)

is in th e process of upda ting it s I nform ational Guide for Roadway L ighti nga nd

recognizes the need to gat her informa tion from tr a nsporta tion ministries and light ing

professionals outside the U nited S ta tes. The informat ion ga thered w ill provide a ba sis

to updat e the Guidea nd will provide a better tool for St a te a nd local aut horities tha t

design, insta ll, opera te, and ma inta in public lighting syst ems.

The st udy w a s co-sponsored by t he U.S. Federa l Hig hw ay Administ ra tion (FHWA), an

a gency of the U.S. Depa rt ment of Tra nsporta tion, a nd by AAS HTO. The purpose of th e

study w as to gat her informa tion relat ed to current roadwa y lighting practices and

innovative solutions used by other countries.

The t eam members brought a var iety of professiona l perspectives t o the st udy.

Representa tion included t he S ta tes of Alaba ma , Pennsylva nia , Texas, an d Wisconsin;

the F HWA; and the I llumina ting En gineering Society of Nort h America (IES NA).

The lighting study was conducted during the first 16 days of April 2000, with

meetings held in Finland, Sw itzerlan d, France, B elgium, a nd th e Netherlands. The

delega tion met w ith professiona ls in the field of roadw ay lighting t o observe and

evalua te t he E uropea n experience in a number of a reas of specific interest, including

sma ll ta rget visibility (STV) a nd lum ina nce design t echniques.

Informa tion wa s collected on th e following 10 prima ry a rea s of interest, which formthe m a in sections of th is report :

P ra ct ica l Ma t t ers

Visibilit y D esign

Lumina nce Design

P a v emen t Ref lect ion Fa ct or s

Tunnels

C ou nt er-Be a m v s. P r o-Be a m L ig ht in g

H igh -Ma st L ig ht s a n d S ign s Rounda bout s

S a fet y Im plica t ions

F ut ur e D evelopm en ts

Based on its observations, the panel developed specific recommendations for the

roadw ay light ing an d safety communities in the Unit ed Sta tes. The recommenda tions

a ppear below, in descending order of priority.


13/83

ix

OVERVIEW

VISIBILITY DESIGN TECHNIQUE

The tea m m embers found t ha t none of th e count ries visited use visibility t echniques

in design. Visibility research with three-dimensional targets is, however, being

conducted in Fra nce a nd B elgium.

Eur opean research suggests t ha t t he visibility concept ma y provide a more complete

a pproach to light ing design , a lth ough more experience is needed. The pa nelrecommends experimenta tion and r esea rch on a ctive roadw ay s.

DYNAMIC ROAD LIGHTING

In t he Netherlands, highwa y engineers have installed a dyn am ic roadway lighting

system t ha t can be operat ed at thr ee levels, depending on the am ount of tra ffic a nd

w ea th er condit ions. The h igh level is 2 cd/m2, th e norm a l level is 1 cd/m2, and t he low

level i s 0.2 cd/m2. The cra sh ra t e for th e 0.2-cd/m2 system, when operated a t low tr affic

volumes, wa s accepta ble. From these results it wa s determined tha t new sy stems w ill

be inst a lled to operat e a t 1 cd/m2 a nd 0.2 cd/m 2. A similar road is current ly being

installed in Finland.The Fr ench a re st udying retroreflectivity a nd a ctive luminous devices. Similarly, the

a cceptability of different ty pes of guida nce systems is being researched in the

Netherlands.

As an a pproa ch to more dynam ic ma na gement of roadwa y lighting, the pan el

recommends investiga ting t he a pplica tion of dimma ble lighting systems, turning off

lighting systems, an d a lternative guidance systems.

PAVEMENT REFLECTION FACTORS

All of th e countr ies use the lumina nce design met hod for r oadwa ys. Severa l countr ies

noted tha t t here ar e problems wit h th e sta nda rd R-ta bles. The initial lumina nce

va lues measured in the field vary from th e values predicted by the design calculations

tha t used the standa rd R-ta bles.

It wa s stressed to the panel tha t , when doing field measurements, the roadw ay must

be dry an d the t emperature must be above the dew point . I t w as also noted tha t

better correla tion betw een ca lcula ted a nd mea sured values is obta ined when

measurements a re ma de in the summer.

The Fr ench ar e resea rching t he photometr ic properties of road surfa ces. The evolution

of roa d surfa ce technology a nd t he use of bright a nd colored road surfa ces

necessitat ed the research. Exam ples of new road sur faces are quiet and wa ter-dra ining pavements a nd very t hin a sphalt ic concretes and sur face dressings. The

French also ar e examining t he possibility of using a virtua l reflectometer for field

measurements.

Pa vement reflecta nce is a n importa nt element of lighting design. The pan el

recommends tha t more research, including field mea surements, be conducted in order

to overcome t he a cknowledged ina dequa cy of the R-ta bles for pa vements.


14/83

OVERVIEW

x

MASTER LIGHTING PLAN

A number of Eur opean cities have ma ster light ing plan s. The plans a re ba sed on

providing sa fety, bea utification, and security for goods a nd people. Urba n light ing is

viewed as a key component of city ma na gement.

The panel encourages the development of master lighting-design plans to improve the

coordinat ion of roadw ay and urban lighting in such ma tters a s lighting levels a ndstyles a nd t hemes for sa fety, security, an d beau tifica tion.

ROUNDABOUT LIGHTING

Ea ch of t he countr ies visited ha s specific recommenda tions for roundabout lighting.

All cited th e importa nce of ha ving rounda bout light levels higher tha n t he levels on

a pproa ch streets.

The pan el recommends tha t t he Eur opean experience in rounda bout lighting be

synt hesized a nd consolidat ed for U.S. application.

CROSSWALK AND PEDESTRIAN-AREA LIGHTING

The Swiss have modified lighting techniques to provide vertical illuminance, which

a llows pedestria ns in crosswa lks to be seen in positive contr a st. The result ha s been a

lowering of fata lities by t wo-thir ds. Other count ries a lso cited t he import a nce of

vertical illumination in pedestrian areas to enhance easy identification.

The pan el recommends the considera tion of vertical illuminance a s a design a pproa ch

to improve safety in crosswa lks and other pedestria n a reas.

ENERGY-ABSORBING POLES

En ergy-a bsorbing poles flat ten upon impact, but do not break aw ay. They a re usedma inly in Finland a nd may be useful in the U nited Sta tes, in area s where breaka way

poles a re not desirable.

The panel recommends investigating the use of energy-absorbing poles as an option

for selected applications.

EXPERIMENTATION

Throughout the t rip, the t eam encount ered ma ny inst a nces in wh ich t he Eur opeans

ga ined knowledge and experience by conducting pra ctica l experiments on a ctive

roadw ays. This meth od permits more ra pid implementa tion of new ideas.

The pan el encourages more innovative experimenta tion on a ctive roa dwa ys a nd t est

tracks.

CRASHES AND LIGHTING

The police in Zurich, Sw itzer la nd, presented a n extens ive accident r eport . The pa nel

found it int eresting tha t t he police ana lyze the cause of a utomobile accidents in th e

Zurich a rea a nd ma ke recommendat ions for lighting a pplica tions.


15/83

OVERVIEW

xi

The pan el recommends the development of report ing syst ems th a t consider t he

lighting conditions a t crash scenes.

EUROPEAN LIGHTING STANDARDS

There is a potent ial t o ga ther a grea t dea l of informa tion from E uropean light ing

documents. The panel recommends furt her evalua tion of the E uropean sta nda rds a nd

guida nce documents t o determine a pplica bility in t he Unit ed Sta tes.

EQUIPMENT QUALITY LEVEL AND MAINTENANCE

The Eur opean light ing equipment genera lly appeared t o be of a h igh qua lity, a nd very

few road wa y lighting outa ges were observed. The lighting syst ems were genera lly

relamped on a group basis, typically on a 3- to 5-year cycle. Maintenance of tunnel

lighting syst ems is generally conducted on a shorter cycle tha t coincides wit h th e

cycle for washing. Necessary r elamping is conducted a t t ha t t ime. It w a s sta ted tha t

the t unnels on the loop, in P a ris, are cleaned every m onth .

The panel recommends t ha t, wh en possible, higher qua lity lighting ma teria ls beconsidered to benefit ma intena nce a nd dur a bility for th e life of the lighting systems.

In a ddition, maint enan ce personnel should be thoroughly t ra ined to ensure th e

integrit y of lighting syst ems.

SIGNS

Severa l count ries ar e beginning t o eliminat e sign lighting by using m icro-prisma tic

sheeting ma teria l. Fra nce a lso is moving aw ay from fixed sign lighting by using

engineering-gra de retr oreflective ma teria l.

The pa nel recommends the use of micro-prisma tic ma teria ls for unlighted overhead

and left-shoulder mounted signs.


16/83


17/83

1

INTRODUCTION

Vehicular t ra vel is increasing t hroughout the world, part icular ly in large urba n a rea s

an d a t a ll hours of the day a nd night . At night , the visual capa bilit ies of huma ns a re

impaired a nd visibility is reduced. Road crashes a t night a re disproport iona tely high

in numbers a nd severity, compa red with day time crashes. In t he Un ited St a tes, the

nighttime fatality rate, weighted for kilometers traveled, is three times the daytime

figure.1,2 One of the major factors contributing to the problem is darkness, because of

its influence on a drivers behavior a nd a bility. Thus, roa dwa y light ing can be an

effective t ool to help ensure efficient a nd sa fe tr a ffic movement . The U.S.

tr a nsporta tion community is interested in identifying cutt ing-edge resear ch a nd

technologies in highw ay a nd roadw a y lighting syst ems, including tun nel illumina tion,

sign lighting, and a ll the methods tha t a re used in t he design of roadwa y lighting

systems.

The American Association of State Highway and Transportation Officials (AASHTO)

is in the process of updating its publication I nform ational Gui de for Roadway

L igh t inga nd recognizes the need to gath er informa tion from tr a nsport a tion

ministr ies and light ing professiona ls ar ound t he world. The informa tion ga thered

could provide a ba sis on w hich t o upda te t he Guide, thereby providing a better tool forState and local authorities that design, install, operate, and maintain public lighting

systems.

Recognizing the benefits th a t could result from a n examina tion of interna tional

practices, a tea m of roa dwa y lighting a nd sa fety experts w a s assembled. The tea ms

mission wa s to observe and document pra ctices tha t migh t ha ve value to the U.S.

tr a nsport a tion community. In April 2000, the panel t ra veled t o five Europea n

count ries (Finla nd, Swit zerland , Fran ce, Belgium, and the Netherla nds) to observe

innovative lighting pra ctices and identify th ose practices tha t could be implemented

in th e Un ited S ta tes. This report describes the findings a nd observa tions of th e group

a nd includes recommenda tions of practices th a t ha ve potent ial for implementa tion inthe United States.

TRIP PLANNING

In 1990, the Federa l Hig hw ay Administ ra tion (FHWA), in coordin a tion w ith AASH TO

an d t he Tra nsporta t ion Resear ch B oar d (TRB ), began an internat iona l tr ansporta t ion

technology r esearch progra m. The program involves assembling t eams of experts in

specific a rea s of tra nsport a tion technology w ho tra vel overseas t o identify

technologies and pra ctices tha t m ight ha ve immediate or near-term implementa tion

va lue in the U nited S ta tes. The cost of sending a group overseas a nd documenting the

findings is significa ntly less tha n t he cost of researching t he technologies and

preparing the appropriate documentation in the United States. In addition, individual

tea m m embers benefit from first ha nd observa tion of th e technology a pplica tions in a

rea l-world set ting.

A scan t rip begins w hen F H WA a nd AASH TO identify th e need to observe

interna tional pra ctices in a pa rticular field. A panel of experts in tha t field is creat ed,

a nd t he panel meets to plan t he key aspects of the tr ip and develop a series of

a mplifying questions tha t a re submitted t o the host countr ies in a dva nce of the tr ip.

Dur ing the trip, panel members meet as a group wit h representa tives of various


18/83

2

INTRODUCTION

organiza tions in each host count ry. Upon its retur n, the panel prepares a report

describing its observat ions a nd r ecommenda tions.

Objective

The objective of this st udy w a s t o review a nd document E uropean experience wit h

roadway lighting systems and advanced technologies, such as small target visibility

(STV) and counter-beam technologies, in tunnels and roadways and for specialgeometries such a s rounda bouts. Findings ma y be incorpora ted in the n ew AASH TO

I nform ational Guide for Roadway L ighti ng, which is due for revision in the near

futur e. The scan tea m a lso set out to observe innovat ive technologies tha t ma y be

implemented in the U nited Sta tes in the near or long term.

The study panel a lso wa s interested in a spects of planning, insta llat ion, operat ion,

ma intena nce, a nd finan cing, a s they relat e to innovative lighting systems. In ga ining

a n underst a nding of innova tive lighting syst ems an d technologies, the panel hoped to

identify both t he similarities an d differences between European a nd U.S. systems th a t

might a ffect implementa tion. The pan el also wa nted t o identify problems a ssocia ted

wit h implementing innovat ive technologies and sy stems a nd t he role(s) tha tnongovernment, private entities ha d in implementing a nd operat ing lighting systems.

Fina lly, the pa nel wished t o observe, firstha nd, the syst ems a nd t echnologies in

opera tion a nd obta in informat ion t o assess their effectiveness.

Team Members

The tea m m embers represented severa l different perspectives including t ha t of the

FH WA, four Sta te depar tment s of tr a nsporta tion (Alaba ma , Pennsy lvan ia, Texas, and

Wisconsin), and the Illuminating Engineering Society of North America (IESNA).

Appendix A lists t he pa nel members, their a ffilia tions, a nd sh ort biographies. Figure 1

shows the pa nel members during their visit to Fra nce.

Meetings

The panel met four t imes thr oughout t he

trip development a nd th e actua l tour, a s

shown in table 1. The first meeting

provided an opport unity to define the a rea s

of grea test int erest an d prepa re a series of

am plifying questions th at the host

count ries could us e to develop progra ms for

presentat ion to the t eam.

Figure 1. The ro ad w ay l ighting scan team : from left , Pau lWatso n, Jim Ha vard , Pau l Lutkevich, Karl Burkett, Balu

Ananthanarayanan, John Arens, Mar ie-Domin iqueGorriga n (ATI), Dale W ilken, Pat H asso n, a nd Jeff Un ick.


19/83

3

INTRODUCTION

TABLE 1. SCHEDULE OF TEAM MEETINGS.

Date andLocation Time Frame Purpose

Wa sh ing ton , D.C. 1/ 13 / 0 0 Determ in e em p h a sis a rea s a n d deve lop a m pl ifying q uest ions

H elsin ki, Fin la n d 4 / 2 / 0 0 (Beg inn in g o f tou r) Pla n trip a ction s a nd em p h a sis a reas

Lyo n , Fra nce 4 / 9 / 00 (M id - tou r) Review find ing s

U trech t, The Netherla nd s 4 / 16 / 0 0 (En d o f tou r) Id en tify key fin din gs a nd deve lo p p re lim in a ry p a n e l

recommenda t ions

Amplifying Questions

To provide the E uropean h osts w ith a clear er understa nding of the issues and

technologies of interest, the tea m prepared a series of a mplifying questions tha tfocused on 10 ma jor t opics, as listed below :

F ut ur e D evelopm en ts

P ra ct ica l Ma t t ers

Visibilit y D esign

Lumina nce Design

High-Mas t , Decora t ive, and S ign L igh t ing

Tunnels

P a v emen t Ref lect ion Fa ct or s C ou nt er -Be a m v s. P r o-Be a m L ig ht in g

Rounda bouts

S a fet y Im plica t ions

The a mplifying questions ar e listed in a ppendix B.

Trip Itinerary

The t our t ook pla ce during th e first tw o weeks of April 2000. Ta ble 2 lists t he

countr ies and cities visited by the st udy pa nel.

TABLE 2. SCAN TEAM ITINERARY.

Dates Countries Cities Ap ril 3 - 4 Fin la n d H e lsin ki

Ap ril 5 - 7 Sw itzerla nd Zu rich Ap ril 10 Fra n ce Lyo n Ap ril 11 Fra nce Pa ris Ap ril 12 Belg ium Lieg e

Ap ril 13 -14 The N etherla n d s U trech t


20/83

4

INTRODUCTION

Note: Only the da tes on w hich th e panel members met wit h hosting officials a re

listed. The ta ble does not include tr a vel days a nd w eekend pan el meetings.

Appendix C lists t he officials w ith wh om t he pan el met dur ing t he tr ip. The hosts

presented informa tion on a wide va riety of lighting t opics, a nd t he pan el observed

ma ny other int eresting pra ctices during th e tour. Man y of the hosting a gencies

provided document s t o the scan ning tea m. The documents referred to in this report

a re listed in appendix D.

REPORT ORGANIZATION

Dur ing th e tour, the panel identified ma ny notew ort hy pra ctices, severa l of wh ich ma y

have current or future value to tra nsporta t ion a gencies in th e United S ta tes. Ea ch

section of this report begins with a brief description of the topic, then documents the

panels observations, and concludes with a recommendation. The final section contains

a summa ry of the pa nels r esearch recommenda tions. Appendix E lists opport unities

for th e team m embers to sha re the informa tion at conferences and t hrough technical

articles and demonstrations.

AMERICAN AND EUROPEAN CONTRASTS

Throughout th e tour, team members w ere continua lly educated on some of th e

significa nt differences betw een the United S ta tes an d the Eur opean count ries visited.

The differences w ere evident in ma ny a reas, including culture, langua ge (both

common and technical), and engineering practices. While the engineering differences

were t he focus of the t rip, the other differences a ffected t he ga thering of informa tion

a nd a lso will ha ve an impact on the a bility of U.S. practit ioners to implement

promising t echnologies or pra ctices.

Culture

Although th e focus of the t rip wa s on innovat ive lighting sy stems, pa nel members ha d

th e pleasur e of experiencing t he people an d fa cilities in ea ch countr y. As th ey tr aveled

on pla nes, tr a ins, subwa ys, buses, a nd t a xis, stay ed in different hotels, a nd int eracted

wit h t he people in ea ch country, the pa nel members w ere a ble to observe man y

significa nt cultura l cha ra cteristics in the five count ries. Man y cultura l

chara cteristics represent nothing more tha n a different wa y of living and give ea ch

a rea its uniq ue identity. Some cultura l chara cteristics, however, have a direct impact

on the light ing syst ems in ea ch country. Many of th e cities visited ha ve very dense,

a ctive populat ions t ha t enga ge in extensive wa lking or bicycling. Comprehensive

tr olley and subwa y syst ems a re used for both w ork and r ecrea tion. Additionally, ma ny

a ut omobiles compete for t he limit ed pa rking. Also, lar ge num bers of people were outa nd a bout in th e center of town a t night . The team m embers surmised tha t th is

night time a ctivity prompted the loca l governments t o light buildings, pa rks, a nd

monuments for the users comfort and security, as well as for display.

P reservat ion of urba n centers is importa nt t o Eur opeans. As a r esult, Eur opeans ha ve

a very strong sense of history a nd t he preserva tion of tha t hist ory. The a ntiq uity a nd

historica l importa nce of Eur opean cities is a m a gnet for tourists an d of great

economic im port a nce.


21/83

5

INTRODUCTION

G enerally, Eur opeans a lso a ppea r t o have grea t r espect for a uthority, which lea ds to

high compliance wit h t ra ffic-contr ol regula tions a nd devices. In ma ny ca ses, the panel

identified pra ctices tha t w ere innovat ive or unique, but th a t w ould ha ve limited

a pplica tion in the U nited St a tes beca use of basic differences in light ing systems a nd

cultures.

LanguageThe pan el members were continua lly impressed by t he a bility of th eir hosts to

commun ica te in E nglish. The ma jority of individuals t he pan el met w ith w ere fluent

in E nglish. Even so, the panel ha d to learn numerous terms, both common a nd

technica l. A few of th e most common a re listed below, with the E uropea n t erm listed

first and the equivalent American term in parentheses.

Mot or wa y (fr eew a y)

C a r r ia g ew a y (t r a velw a y or pa v ed roa d w a y )

D u a l ca r r ia g ew a y (d iv id ed h ig hw a y )

H a r d s hou ld er (pa v ed sh ou ld er )

C olum ns (poles)

J u n ct ion (in t er sect ion )

Lorry (t ruck)

P et rol (ga solin e)

C on tr ol gea r (ba lla st )

Engineering

It w as evident t o the team m embers tha t th eir European counterparts ha ve had ma ny

of yea rs of experience with designing solutions an d ma na ging lighting problems incities an d rur a l ar eas on a ll classes of roa dwa ys. The panel found ma ny solutions

pra ctica l, effective, a nd, more often t ha n not, new a nd creat ive. Europea n engineers

a re utilizing new t echnologies fa ster th a n ma ny of their U.S. counterpart s, a nd

Eur opean t ra nsport a tion agencies appear t o be more progressive in testing a nd

implementing new technologies and applications of lighting systems. The difference

ma y be due, in lar ge part , to the a ggressive a nd progressive research program s in the

individual countr ies. Many of the solutions observed on roadwa ys w ere certa inly more

adva nced tha n those tha t a re used on roadwa ys in the United Sta tes. Exa mples

include the use of variable lighting levels, depending on time of day, weather, and

tr a ffic movement; t ra ffic guida nce systems, in pla ce of fixed, overhead lighting

systems; energy-absorbing poles, in areas where frangible poles could not be used;

ma ster lighting plans t o guide long-term development; a nd vertical illumina tion in

crosswalks.

One of the most significa nt engineering contr a sts is th e Europeans willingness to

ga in knowledge a nd experience by conducting pra ctica l experiments on active

roadw ay s. This meth od permit s ra pid implementa tion of innovat ive idea s. In defense

of the lack of experimenta tion in th e Un ited S ta tes, Europea ns do not experience the

a mount of litiga tion tha t regular ly occurs in th e St a tes. Therefore, in E urope, it is

easier t o do a ctual research on public roa ds.


22/83

6

PRACTICAL MATTERS OFROADWAY LIGHTING SYSTEMS

In t he area of practical m at ters , the panel wa s interested in examining details

involved with design, verifica tion, opera tion, a nd ma intena nce of Eur opean r oa dwa y

lighting systems.

DESIGNG enerally, lighting is insta lled in Eur ope at a higher light level tha n is used in the

U nited St a tes, a nd th e roa dwa y lighting is more uniform in a ppea ra nce. The higher

lighting levels an d more uniform a ppea ra nce a re the results of many st udies over the

year s tha t exa mined visual performa nce a nd visua l comfort. Additionally, the panel

hear d th e Europea ns equa ting high er light levels with driver comfort, which, they

believe, produces a h igher level of sa fety. (It should be noted, however, tha t n umer ous

stu dies ha ve been conducted, the result s of which ha ve not been conclusive. Fren ch

experts pointed out th a t wh ile higher light levels contribute t o driver comfort, th ey

ma y a lso creat e a false sense of safety, ma sking drivers levels of fat igue or

intoxication.)

In E urope, the lumina nce design method is widely used for sta nda rd road sections.

The illuminance design method is used for more complex situations such as

intersections, pedestrian crossings, rounda bouts, residentia l a reas, rest a rea s, a nd

bicycle-pat h lighting. Curr ently, each count ry visited ha s its own design sta nda rds

tha t a re based on the documents produced by the Commission Int erna tionale de

lEclaira ge (CI E). Among countr ies the light ing levels a re a pproximat ely the sa me for

equivalent cla sses or t ypes of roadw ay s. In a ddition, each count ry h a s developed its

own guide for lighting designers to consult. The guides a ddress ma tt ers of mount ing

height, spacing, overha ng, la mp wa tt a ge, lam p type, a nd t ype of lumina ire.

Of all th e countr ies visited, only S wit zerland is not a member of the E uropea n U nion(EU ). However, all a re w orking t hrough th e Comit Eu ropen de Norma lisat ion

(CE N), which is th e Eur opean C ommit tee for S ta nda rdiza tion, to produce ha rmonized

lighting sta ndar ds tha t w ill apply to all EU members.

It wa s common t o find the design process outsourced t o contra ctors. In Finla nd, the

governm ent ha d n egat ive experiences w ith performa nce specifica tions, beca use

contr a ctors reduced insta llat ions t o the minimum limit a cceptable, which reduced

long-ter m suit a bility. To solve th e problem, th e ty pica l specificat ion is wr itt en, based

on experience, to rea d ma nufa ctur er, ca ta log number, or sim ila r.

In Belgium, most (80 percent) of the motorways (freeways) are continuously lighted,

for sa fety rea sons. The tra ffic intensities on B elgian motorwa ys a re very high a nd th edista nces betw een interchanges a re short (ea ch 3 to 4 km) beca use of th e high degree

of urba niza tion. In less densely populat ed ar eas, only t he interchan ges of the

motorwa ys a re lighted.

As noted ear lier, in the Net herla nds, motorwa y light levels ha ve been r educed to

a pproximat ely the sam e ran ge of values as t hose used in the Un ited St a tes. The

uniformity of lighting is, however, still typically European. The Dutch seem to be

sa tisfied with the lower light levels.


23/83

7

PRACTICAL MATTERS OF ROADWAY LIGHTING SYSTEMS

Finnish representa tives mentioned tha t t hey ha ve ceased using low-pressure sodium

(LP S) as a light source, prima rily beca use of the cost of th e lam p.

VERIFICATION

Rather than testing individual luminaires for tunnel applications, field

mea surements of lighting levels are conducted on the ma jority of tunnels in

Sw itzerla nd. Roa dwa ys, however, are mea sured only if there a ppea rs to be a problem.

(In Finlan d, ca lculat ions a re verified, but no field verifica tion is current ly conducted.)

B eca use lighting contr a ctors can not be held a ccounta ble for r oa d surfa ces, verifica tion

is usua lly done in lux. The French designs a re ba sed on lumina nce and verified by

measuring illuminance (lux).

EQUIPMENT QUALITY LEVEL AND LIGHTING SYSTEM MAINTENANCE

The pa nel review ed some of th e Eur opea n

lighting equipment and, in general,

concluded tha t it wa s of a higher quality

level tha n tha t generally available in theUn ited Sta tes. In a ddit ion, the team noted

tha t t he relamping maintena nce of the

lighting sy stems wa s very good (see figure

2). Typically, th e road lig ht ing sy stem s a re

rela mped on a group ba sis, on a 3- to 5-yea r

cycle.

The French a re experimenting w ith r emote

control and monitoring of public lighting

systems. Monitoring da ta will include time

of operat ion, proper operat ion, a utoma tictroubleshooting, and problem notification.

Cont rol includes on/off contr ol an d possible futu re dim ming. Fixt ures em ploy

electronic high-pressure sodium (HPS) ballasts.

As the tea m tr aveled around the five count ries at nigh t, it ha d ma ny opport unities to

observe ea ch count rys lighting. G enerally, the lighting wa s better ma inta ined tha n

compar a ble lighting in t he Un ited St a tes. The tea m ra rely observed unlit lumina ires

an d wa s impressed w ith th e overall uniformity a nd qua lity of the lighting.

The panel noted tha t E urope shar es a problem wit h th e Unit ed Sta tes, i.e., ma tching

existing photometrics, or overa ll lighting performa nce, on a n existing system. I n

discussions w ith r epresenta tives in va rious countries, it beca me evident tha t t heEur opeans h ave not achieved a n effective mean s of ma inta ining the photometric

performa nce of the light ing syst ems. Once a system is designed a nd built , no

systematic lighting mea surements a re ma de in the long term an d no controls are

placed on r epla cement lumina ires. This causes a ra pidly deteriora ting performa nce of

th e syst em. The scope of effort requ ired t o correct t he problem a nd t he cost in volved

a re enormous, wh ich ha s prompted th e Europea ns not to require ma intena nce of

initial performance levels.

Figure 2. M aintena nce of lum inaires, Sw itzer land .


24/83

8


In B elgium, the regions or cities are responsible for th e insta llat ion a nd ma intena nce

of lighting insta llat ions; contr a ctors a re hired on a low-bid basis t o perform the

insta llat ion a nd ma intena nce. No contr ols or contr a ct requirements a re ma de to

ma inta in photometric performa nce of the lighting syst ems. Contr a ctors a re

responsible for obta ining fixtur es a nd other replacement items. Contr a ctors do not

typically ha ve a lighting engineer or a lighting-design expert on staff a nd ha ve litt le

incentive to ma inta in th e photometric performa nce of existing systems.

In-depth discussions w ith t he B elgians on ma intena nce issues confirmed th a t t heir

concerns are similar to some U.S. concerns. These concerns are that maintenance

personnel a re not capa ble of determining the photometrics of the existing system a nd

that they are not able to determine acceptable alternatives. Contractors typically

replace lumina ires with wh a tever is in stock. It is difficult t o write a nd enforce

specifica tions for photometrics for replacement fixtur es th a t would provide equiva lent

lumina nce values.

The French a llow the inst a lling contra ctor t o select fixtur es to meet a lumina nce

calcula tion specifica tion. French r epresenta tives sta ted t ha t contra ctors do not

usually understand the luminance design method and pay little attention to it . Fieldmeasurements of the built system are made with illuminance values. Maintenance

personnel do not a tt empt t o mat ch replacement fixture photometric performa nce to

that of initial fixtures.

The problem is more critical on lighting systems designed for lower light levels, where

poles are spaced fart her a par t. On such

systems, near by fixtures will have a h igher

percenta ge contribution at each point, a nd

distant f ixtures will ha ve a lower

percenta ge contr ibution, making fixtur e

photometric performan ce increasinglyimportant for maintenance of the system

performance.

Tunnel lighting syst em ma intena nce is

done on a shorter cycle, a pproximat ely tw o

to four times per year, which coincides with

the common wa shing a nd spot rela mping

cycle. The pa nel noted th a t a ll the t unnels

on the loop in P a ris a re cleaned every

month, a s shown in figure 3.

POWER CONSERVATION

The Sw iss Energy Administr a tion has a sta nda rd, not a law, on the lighting density

limit (wa tt s/m 2) tha t sometimes a ffects the design light levels. The Administr a tion

a lso limits t he a mount of an nua l energy consum ption (KW h/yr ) for light ing. To meet

the r equirements, some lighting is r educed in the la te night , typica lly from 11P M t o 5

AM.

Figu re 3 . Tun ne l clea ning in Paris.


25/83

9


Although Fr a nce has no limits on power

consumption, it is not unusua l to dim th e

lighting, to save energy, between the hours

of 10 P M and 6 AM. A recent survey by the

Center for St udies on U rban P lanning,

Tra nsport , Ut ilities, and P ublic

Constructions (CE RTU ) shows t ha t one-thir d of French town s decrea se light ing a t

night , and 8 percent of the netw orks a re

dimmed at night .

In Finland, an analysis of lighting-system

costs over 20 year s shows t ha t electric

energy is tw o-th irds of t he t ota l cost. To

save energy, some Finnish road wa ys ha ve

high /low-sty le cont rols, a nd light levels ar e

lowered. The m otoring public ha s not

complained.

MASTER LIGHTING PLAN

Throughout the scan, t he panel noted tha t

a number of cities ha d developed forma l

ma ster light ing plan s. The plans a ccount ed

for economic and cultur a l changes, the

public imag e of the city, an d t echnologica l

development s. The benefit s of such a plan

are that it organizes the different functions

of lighting, plan s the different pa rts of the

city, and schedules the expenditures. For example, the City of Paris has developed ama ster urban lighting plan tha t is ba sed on t he safety of the roads, beautificat ion, and

security for goods an d people (figures 4 a nd 5). Lightin g is employed to cha nge t he

ima ge of the environment, re-link different par ts of the city, and ind ica te t he na tur e of

the site. Essentially, planners consider

urban lighting to be one component of

managing the city.

ENERGY-ABSORBING POLES

CE N ha s developed a new sta ndar d for

breaka wa y a nd energy-a bsorbing poles,number EN12767, Passive sa fety of

support stru ctures for r oad equipment.

New t ypes of poles meeting t he sta nda rd

a nd suit a ble for w ind speeds of up to 23 m/

s (a pprox. 50 mi/h) ha ve been in st a lled.

Figure 6 shows a n exam ple of how th e

energy -a bsorbing pole w orks. The pa nel

Figures 4 & 5. M aster l igh t ing plan s, Par is.

Figure 6 . Results of crash test of energ y-ab sorbingpo le .


26/83

10


thought tha t t his item would ha ve applicability in a reas w here it is not currently

a dvisable to use breaka wa y poles.

Additionally, the panel was shown several bored-center-hole methods used in Finland

to ma ke wooden poles break aw a y w hen impacted by a vehicle.

Cr a sh t esting of roa dside devices is based on CE N sta nda rd procedures. The CE N

procedures a re directly modeled a fter t he U.S. crash-test criteria specified in Na tionalCooperat ive Highwa y Resear ch Pr ogram (NCH RP ) Report 350, wit h modifica tions; for

example, pickup tr ucks a re not included in Eur opean tests.

LITIGATION

Litigat ion about lighting did not a ppear t o

be an issue in Eur ope, a s it is in the U nited

St a tes, wh ich ma y be explained, in par t, by

differences in t he lega l syst ems. The

Eur opean a pproa ch a lso is different. For

example, the Dutch have developed ana tional lighting policy th a t includes

dimming. It wa s pointed out to the team:

If you follow the policy, no one can sue

wh en you tur n th e light s out.

LIGHT POLLUTION

The team w as not ma de awa re of any

forma l sky glow r estrictions in E urope.

There is certa inly, how ever, an a wa reness

of the problem a s well a s a technica l

report, Guid el i nes for M in im izingSkyglow,

CI E 126, 1997. Results of several st udies

by R-Tech in B elgium on th e am ount of

uplight genera ted by va rious types of

lumina ires were presented t o the pa nel in

both Fra nce and B elgium and a re shown in

figures 7 a nd 8. In la ter feedback the panel

wa s told tha t , in Belgium, the upwar d light

ra tio of t he lumina ires is limited. We a lso

were informed tha t t he light pollution

figures are being updat ed and tha t t his

informa tion will be ava ilable in the fall of

2001. To reduce th e t ota l a mount of

upward flux, the following guidelines have to be followed:

1. Reduce upwa rd light output ra t io (ULOR) as much a s possible.

2. Maximize the utilizat ion factor (K) in such a w ay t ha t it should approach the

downwa rd light output r a tio (DLOR ) a s much as possible.

Figu res 7 & 8. Results of R-Tech s stud y on l ight

pol lut ion.


27/83

11


3. In the case of a roadw ay lighting designed in luminance, ma ximize the

lum ina nce efficiency express ed in cd/m2/lux.

4. In t he case of an outdoor insta llat ion designed in illuminance, apply strict ly

the requested illumina nce level.

WARRANTS

Ea ch count ry visited ha d different w a rra nts, as noted below.

Belgium

A large proport ion of paved r oadwa ys in B elgium a re light ed. The continu ous light ing

of th e motorwa ys betw een inter cha nges ha s a lum ina nce level of 1 cd/m2 in the

Flemish region a nd 1.5 cd/m in t he Wa llonia r egion; th e inter chan ges a re lit t o a

lum ina nce level of 1.5 cd/m2.

Switzerland

The official practice on Swiss federal highways (motorways) is to light only junctions

(intersections). Highwa ys in urba n a reas a re lighted in th e neighborhood of lighted

urba n roads or in a rea s wit h higher r isks. The normal r oads (mixed tra ffic) a re

ma inly lighted in urban a reas.

Finland

In Finland, wa rra nts a re very deta iled, and safety is used as a just ificat ion for the

insta llat ion of lighting. One of th e specia l rea sons cited for light ing t wo-lan e roadw ay s

wa s the existence of an a djacent, lighted pedestria n wa y or light ed bike pa th.

Approximat ely 20 percent of the r oads in Finla nd a re lit .

France

In Fr a nce, responsibilities for lighting a nd its ma intena nce var y a ccording to the

own er of th e roadw ay. The na tional government is responsible for n a tional r oads a nd

motorways, counties are responsible for county roads, and cities for city roads.

Individua l towns a re responsible for th e lighting of nat iona l and county roads w ithin

an urban ar ea. Nat iona l roads m ust be lighted a s follows:

> 5 0 ,000 Avera g e Da ily Tra ffic (ADT) Genera l lig h tin g

25 ,0 00 to 50 ,0 00 ADT w ith in tercha ng es < 5 km a pa rt Gen era l lig htin g

25 ,0 00 to 50 ,0 00 ADT w ith in tercha ng es > 5 km a pa rt In terch a ng e on ly

< 25 ,0 00 ADT In terch a ng e on ly

The Netherlands

As in Fra nce, individual town s in the Netherla nds esta blish their own lighting

policies. At the na tional level, specific wa rra nts were w ritt en in 1990, referred to a s

the 1990 Wa rra nts. The wa rra nts to insta ll lighting a re a s follows:


28/83

12


Always Light :

Four or mor e la nes

Dua l car riageway w ith 1,500 vehicles/hour/lane peak

Single car riagewa y with 2,000 vehicles/hour/lane peak

Single ca rria gewa y wit h 1,800 vehicles/hour/lan e peak, if slow-moving vehiclesa re present

Since 1997, an a dditional a ssessment is required, a s follows:

1. Does the road meet the 1990 Warra nts?

2. Does the road go through or near a scenic area?

a . I f no, then ins t a l l l igh t ing

b. I f yes, then move to No. 3

3. Conduct a supplementa ry study to consider lighting alterna tives.

a . Can g la re screens be used?

b. Is guidance l ight ing poss ible?

c. Ca n the l ight ing be switched or dimmed?

d. Is lighting a cceptable, in view of cost/benefit?

4. Reach a conclusion. If the decision is to install l ighting, insta ll extra measures

such a s the ability t o dim or tur n off during lat e night.

As of the t eams visit , a new lighting policy for highwa ys wa s being writ ten. It

conta ins t he following elements:

1. Tra ffic Safety: only enough light for tr affic safety.

2. En ergy Efficiency: goa l of 10 percent improvement by 2010; not tra ding lives

for energy consumption.

3. Environmenta l C onsequences: (see above a ddit ional 1997 assessment).

4. Effects on Road Ca pacity: based on research at the Technical U niversity of

Delft , a ddition of sta nda rd lighting shows a 4 percent improvement.

(Cur rently, the D utch stu dies do not include th e effects of dyna mic lighting on

road capacity.)

5. Adminis t ra t ion a nd Maintenance of the Roadwa y.

En vironmenta lists in the Netherlan ds ha ve raised consciousness about potent ial

impacts of lighting on a nima l behavior. Huma ns, too, are included in t he debat es

some people wan t t o live where it is da rk a t n ight. The efforts of environmenta lists

a re chan ging t he lighting policy.


29/83

13


PANEL RECOMMENDATIONS

Develop master l ight ing des ign plans t o improve the coordinat ion o f roadway

a nd urba n lighting in such ma tt ers as lighting levels, styles, a nd th emes for

safety, security, and beautification.

Investigate the use of energy-absorbing poles as an option for selected

a pplica tions. Ca reful investiga tion should be mad e into the a dequa cy of thesedevices, considering t he w ide ra nge of vehicle ma ss a nd speed on U.S.

highways.

When poss ible, cons ider qua l ity l ight ing ma teria ls to benefi t ma intenance and

dura bility for t he life of the light ing systems.

Thoroughly t ra in ma intenance personnel to mainta in the integrity of the

lighting systems.


30/83

14

VISIBILITY DESIGN

The IESNA recently approved a revision to its publication RP-8, Ameri can N ational

StandardPractice for Roadway Li ghti ng. The r evision in cludes th ree met hods for

designing continuous lighting systems for roadw ay s: illumina nce, luminan ce, and

STV.

DESIGN

One of the prima ry rea sons for conducting th e Europea n study wa s to meet w ith

leading experts in t he field of roa dwa y lighting to find out a bout their experiences

wit h using a visibility design metric.

While the pa nel found t ha t a lot of resear ch is being done in t he a rea of visibility, none

of the resea rch ha s yet been implemented int o everyda y pra ctice. In more tha n one

count ry, tea m mem bers hea rd t he w ords, We ha ve no pra ctical experience, wh en it

came t o applying the visibility design techniques.

B eca use of a n egat ive experience, the S wiss ha ve cha nged their a pproa ch to lighting

crosswalks. They used to shine lights directly across the crosswalk, but discovered

tha t, when a t t he curb, the pedestrian wa s less visible beca use the background va ried,from buildings in some places t o dar kness in others. The S wiss n ow light crosswa lks

from the side, so the pedestria n is highlight ed in positive contr a st. La ter input from

the French confirmed the Sw iss approa ch, but included the caveat t ha t th e main risk

is tha t pedestr ian s often believe they a re seen by drivers wha tever the light

distribut ion a nd w eat her conditions, even if they a re not in the zebra ma rking.

The panel wa s shown roa dwa ys in Finland t hat appeared to have relat ively

nonuniform lighting. It wa s thought t hese lighting syst ems might provide a higher

visibility level. Subsequent calculat ions by a tea m member ha ve, indeed, shown t ha t

this r oa d exceeded a ny lumina nce and S TV requirements in t he new ANSI/IE SNA

RP -8-00. Nat ura lly, the ultima te mea sure of the qua lity of this t ype of design will bethe change in the number of crashes. Crash dat a were not a vailable at the t ime of the

visit .

RESEARCH

The pan el wa s pleased to notice the a mount of visibility r esearch being done in both

Fra nce a nd B elgium. Team m embers saw spa tia l frequency a na lysis by Fa st Fourier

Transforms being used by several people (Eric Dumont, Philippe Boogaerts, etc.) to

describe informa tion content of a scene or border (edge) cont ra st. Addit ionally, Mr.

B oogaerts ind ica ted t ha t t he Fast Fourier Tra nsform is a lso used in th e processing of

the ima ges of cha rge coupled device (CC D) ca mera s. Both countries ha ve selected the

visibility m odel a nd equa tions of Dr. Werner Adria n a nd a re using thr ee-dimensiona l

ta rgets. Representa tives in both count ries told th e panel tha t t he visibility concept

provided a more complete approach to lighting design a nd supplemented t he

informa tion provided by the lumina nce approa ch t ha t is commonly used thr oughout

Europe. The approach, which utilizes three-dimensional targets, results in very

uniform ligh tin g (see figures 9 an d 10).

The use of th ree-dimensiona l ta rgets by the Fr ench a nd B elgians provides cont ra sts

within the ta rget , thereby ma king the ta rget more visible.


31/83

15

VISIBILITY DESIGN

Figure 10 shows a typical thr ee-

dimensional t ar get used by the B elgians t o

develop simula tion softwa re. The B elgians 3

found good correlation between panel

ratings and STV calculations for 20 percent

ta rgets , but s ta ted tha t the visual ta sk of a

driver can not be considered a s detection,wit hin a useful time, of unexpected sma ll

sta tic ta rgets. They fur ther sta ted, The

use of STV ass umes fu ll use of (fa ctors)

a ffecting visibility a nd knowledge of the

limit a tions of t he concept. They w ere

ada ma nt a bout t he need to include

head lights int o the ca lculat ion of visibility.

B a sed on extensive resea rch done by

J a cques Lecocq, th e French ha ve proposed

tha t a s imple minimum t ar get visibilitylevel (VL) metric is all that is necessary.

Mr. Lecocqs research is based on

tra nslat ing a m odel roadwa y into a

computer program tha t a llowed ma ny

observer tr ials a nd t he ra pid collection of

da ta (figure 11). The pa nel noted t ha t Mr.

Lecocqs model relied on a pproximat ions of

key fa ctors. These fa ctors include th e use of

Lambertian distribution calculation of

light reflected from the pavement a nd the

sha dow effect of mult ifaceted ta rgets. Mr.Lecocq noted th a t, as ta rgets get la rger, the

visibility a lway s becomes grea ter. Large

targets develop contrasts within

themselves, as opposed to sma ll ta rgets,

which are alwa ys viewed aga inst their

background, i.e., the roadw ay surfa ce.

The nine possible target positions are

shown in figur e 12, a view of Mr. Lecocqs softw a re. The softw a re permit ted

experimenta tion tha t determined t he minimum visibility level needed for a dequa te

lighting.

B a sed on a n R2 roa dwa y, a 0.35-s observa tion time, and a 20 percent reflectan ce

ta rget, th e results of the study ind ica te tha t a minimum visibility level of 7 is needed

for good visibility.

U sing a ra y-tra cing computer progra m called Radia nce, the B elgians ha ve developed

synt hesized computer ta rgets th a t replica te real-w orld, illumina ted, three-

dimensiona l ta rgets on a demonstra tion roadwa y, as shown in figures 13a, b, and c.

Figure 9. Uniform vs. non uniform l igh ting .

Figu re 10. Typica l three -d im en siona l targ et.


32/83

16

VISIBILITY DESIGN

Studies utilizing the synthesized images

ha ve shown excellent correla tion betw een

the calculat ed levels of visibility a nd t he

subject assessments of the observers for

both fla t 20-cm x 20-cm a nd spherical

ta rgets (appendix D).

In a ddit ion, the B elgians believe tha t t heir

work shows tha t good uniformit y on a

poorly lig ht ed (


33/83

17

VISIBILITY DESIGN

crashes. If circumstances in Switzerland

ar e similar to those in the United St a tes,

the va st ma jority of pedestria n fa ta lit ies

occur aft er da rk. The Sw iss studied th e

crosswalks and have based new crosswalk-

a nd rounda bout-lighting r ecommendat ions

on the visibility principle of highlightingobjects in positive cont ra st. As sh own in

figur e 16, poles ar e positioned so tha t

pedestria ns a re seen in positive contr a st,

w hen light levels a re below 2 cd/m2. No

specia l pole positioning is r equir ed for light

levels a t or a bove 2 cd/m2. Insta llat ion of

the new light ing resulted in a tw o-third s

reduction in pedestrian-vehicle crashes,

but a n increa se in min or vehicle-vehicle

crashes, typically rear-enders, resulting

from q uick stops.

PANEL RECOMMENDATIONS

E u r opea n res ea r ch s ug ges t s t h a t

the visibility concept may provide a

more complete approach to lighting

design, though more experience is

needed. The pa nel r ecommends

experimenta tion and r esearch on

active roadw ays.

Th e pa n el r ecommen ds t h econsidera tion of vertical

illuminan ce a s a design approach to

improve pedestria n sa fety in

crosswalks and other pedestrian

a rea s. It a lso recommends resea rch

into the rela tive benefits betw een

positive- and negative-contrast

lighting techniques and

development of appropriate levels.

Figure 13a. Demonstrat ion roadway with three-

d im ensiona l spheres and squa re , fla t ta rgets.

Figure 13b . Photog rap hic im ag e (zoom ) of targets.

Figu re 13c. Synthesized im ag e of targe ts.


34/83

18

VISIBILITY DESIGN

Figure 14. Synthesized con figu ration o n ro ad surface(R1 q

0= 0.1).

Figure 15. Synthesized con figu ration o n road surface

(R4 q0

= 0.1).

Figure 16. Lighting schem e for crossw alks,Switzer land.


35/83

19

LUMINANCE DESIGN AND PAVEMENTREFLECTION FACTORS

LUMINANCE DESIGN TECHNIQUE

For 25 years, the luminance design

technique has been successfully used on

ma jor motorwa ys a nd tun nels in Europe.This method is based on the wa y th e

huma n eye sees; tha t is, road surfa ces ar e

ma de visible by light reflected from t hem

a nd ent ering t he eye of th e observer.

The pan el saw ma ny exa mples of good

lighting th a t resulted from the use of this

design technique. Exam ples a re shown in

figures 17, 18, an d 19.

Eur opean r oa dwa ys a re lit to levels more

tha n tw ice as high as t hose in the U nitedSt at es, and with better uniformity. Belgian

experts expressed th e opinion t ha t a high

degree of pavement uniformity yields good

driver comfort. They are confident that

driver comfort equa tes t o driver sa fety.

They were not, however, aware of any

forma l studies linking driver comfort t o

safety.

B a sed on t he B elgian experience, expert s

suggest t ha t roadw ays lit to levels between1 a nd 2 cd/m 2 produce good visibility, while

lighting t he roadw ay to less tha n 1 cd/m2

does not y ield good visibility. In a ddit ion to

light level, good visibility in wet conditions

also depends on the locations of luminaires.

For exa mple, in Finla nd, the t eam observed

lighting over the roadw ay.

PAVEMENT REFLECTION FACTORSAND R-TABLES

B eca use the lumina nce design method

depends on road surfa ces being ma de

visible by light reflected from roa ds a nd

ent ering t he eye of th e observer, the

reflection propert ies of pa vement become

a n integra l pa rt of the light ing-design

process. The exist ing pavem ent reflection

ta bles, th e R-ta bles, w ere published in 1976

a nd ha ve been used in luminan ce design

Figu re 17. Wevelgem Tun ne l, Belgiu m .

Figure 18. Hig hw ay n ear Helsinki Airpo rt, Finland .

Figure 19. Hig hw ay n ear Helsinki, Finland .


36/83


37/83

21

LUMINANCE DESIGN AND PAVEMENT REFLECTION FACTORS

properties ca used by tra ffic. Note th a t t he wh eel-rut pat hs a lso ha ve a m uch different

specularity than the other pavement areas, which makes it difficult to measure the

lumina nce of th e overall pa vement. All measur ed lumina nce values must be qua lified

a s to the location on t he pavement, but meth ods for determ ining th e overall

lumina nce value from collections of individua l points ha s not been esta blished in

Eur ope or in t he U nited S ta tes. This

example illustr a tes th e difficulty t ypica llyencountered when a tt empting to enforce

lumina nce specifica tions or w hen verifying

designs.

Luminance measurements t aken on the

tw o la nes show t he righ t la ne, a t 140 cd/m2,

to have tw ice the luminan ce level as t he

one on t he left , 70 cd/m2.

The Sw iss noted problems with st a nda rd

R-ta bles a nd ha ve obta ined different

results init ially t ha n t hose designed w ithsta ndar d R-ta bles. In a n a ddit ional

conversa tion w ith Werner

Riemenschneider, however, he cla rified t ha t

a fter the pavement ha d ag ed for 6 to 12 months, the Swiss ty pica lly found th a t th e

mea sured avera ge values were wit hin 15 percent of the avera ge design va lue, usua lly

on the high side.

In the good cases t he B elgians n oted discrepancies of less tha n 10 percent, wh en

compar ing mea sured lumina nce levels aga inst calculat ed levels for pavement s, wh ere

the r eflection cha ra cteristics ha ve been determ ined.

NEW TYPES OF PAVEMENT

As mentioned earlier, pavement types

ha ve been invented since the original R-

ta bles w ere conceived. The F rench noted

increa sed usag e of new surfa ces over t he

pa st 10 yea rs. These surfa ces include a

number of wea ring courses a nd porous

a sphalt , i.e., wa ter-dra ining pavement.

Porous a sphalt s ta bilizes in a unique

wa y. It becomes more diffuse an d it sbrightn ess increa ses, a s is shown in

figures 21 an d 22.

Figur es 21 a nd 22 show comput er-

generat ed ima ges of th e reflection

characteristics when viewed from typical

a ngles down t he roadw ay. The a ngle

most frequently encountered in t he past

Figure 20. M i lchbu ck Tunn el, Sw itzer land.

Figure 21. New po rous a spha lt.

M

s.

Corine

Brusque

ofth

e

French

Laboratoire

CentraldesPontsetCha

usses.


38/83


39/83

23

LUMINANCE DESIGN AND PAVEMENT REFLECTION FACTORS

In F inlan d, the sta nda rd R- a nd W-ta bles are used, wh ile the other countr ies tha t t he

tea m visited use only t he R-ta bles. In S wit zerland , the W-ta bles tha t w ere developed

in Scandina via a re not used. Ra ther, the Sw iss studied 10 typical insta llat ions a nd,

ba sed on experience, deter mined th a t, for t heir purposes, 2 cd/m2 under d ry conditions

wa s a lso a dequa te in w et conditions. Sw iss experts found no operat iona l difficulties

with that approach.

PANEL RECOMMENDATION

Pavement re f lectance is an important e lement o f light ing design. The panel

recommends tha t more research, including field mea surements, be conducted

in order t o overcome t he a cknowledged ina dequa cy of the R-ta bles.


40/83

24

TUNNELS

As ment ioned ea rlier, tunnel light ing ha s been upgra ded in t he past 10 year s. As

defined in t he technica l report, Gui de for the Li ghti ng of Road Tunnels and

Und er passes, CIE 88, 1990, good tunnel lighting should ensure that traffic, both

during day an d nightt ime, can approach, pass through, an d leave a t unnel, at the

designat ed speed, wit h a degree of safety a nd comfort not less tha n tha t a long

a djacent stret ches of open r oad.

In t he past 10 year s, techniques for excava ting t unnels ha ve improved, ma king

tun nels a more at tra ctive option. For exa mple, Finland is current ly w orking on a

bypass tha t goes under, not a round, the Cit y of Helsinki. Additionally, while ty pica l

tun nels are stra ight drive-thr oughs, the tea m observed tunnels in Eur ope tha t

contained merges and diverges and the

team even visited an underground

rounda bout (figure 24). The u nderg round

roundabout, which is part of a ma ss tra nsit

sta tion at Fr a uenfeld, in the Thurga u

Ca nton, Swit zerland, includes not only

through roadw ays, but a lso an entrancea nd exit to a n underground parking lot

(figure 25).

Sw iss experts believe tha t good wa ll

luminance is necessary to provide good

guida nce for m otorists. Addit ionally, they

have observed that most people perceive

tunn els lit w ith fluorescent sources to be

brighter and more comfortable than

tunn els lit on the road t o the sam e level

with point sources, probably because of thehigher wa ll luminance norma lly at t ained

wit h fluorescent lumina ires. Although

var ious light sources are being u sed, long

tunn els a re generally lit wit h electronica lly

ballasted, dimmable fluorescents. That

approach easily ada pts to the integrat ed

contr ol systems u sed on a ll the t unnels

tha t t he tea m observed. The integra ted

systems use a lumina nce meter to adjust

the light level in t he thr eshold zone.

Lighting contr ol systems can be integra tedinto the tra ffic mana gement systems, and

tra ffic volume can be a dded to the contr ol

elements. (Tra ffic control center s a re

discussed later under Future

Developments.)

The prima ry difficulty in tu

euro road lighting

Documents