DIVISION 4
Lighting and Signalling for Transport
Division 4 Officials
• Division Director: Ad de Visser
• Division Secretary: Hans Huijben
• Division Editor: Doug Simpson
• Webmaster: Tapani Nurmi
New TCs
• TC4-46 300mm Traffic Light (Carl Andersen)
• TC4-47 Use of LEDs in visual signalling (Steve Jenkins)-
• TC 4-48 White light in road lighting (Stephan Voelker)
New Reporterships
• R4-14 Road lighting and accidents (Carl Andersen)
• R4-30 Measuring systems for in situ road characteristics (Guiseppe Rossi)
• R4-31 Inventory of D4 pubns. on possible energy improvement review (Hans Huijben)
• R4-32 Reflection properties of road surfaces (Cyril Chain)
• R4-33 Review of CIE pubn. 72 (Norbert Johnson)
• R4-34 Retroreflective and other passive devices as energy savers (Norbert Johnson)
TCs near completion (1)
• TC4-10 Automobile Lighting Systems – ready for Div. Voting
• TC4-16 Recommended File Format for Electronic Transfer of Luminaire Photometric data –TC is dealing with Div. Voting comments
TCs near completion (2)
• TC 4-26 Systems for Measurement of Photometric Quantities of Road Lighting Installations – ready for voting by TC members
• TC4-37 Road Transport Lighting for Developing Countries – issued, Report available as free download
• TC4-43 Emergency Lighting in Tunnels – ready for Div voting
Developments in Road Lighting
• Driven by:– Technology developments (new measurement
techniques, new light sources, controllable electronic ballasts)
– Energy efficiencies
Adaptive Road Lighting (1)
• Installations will be responsive to:
• Weather conditions
• Traffic volume
• Traffic speed
Adaptive Road Lighting (2)
• Central control will monitor real-time measurements of:
• Pavement luminance• Traffic volume
• These are compared with criterion levels and the road lighting changed if necessary.
Road Surface Reflectance (1)
• Growing realisation that new road surfaces are not well characterised by the standard CIE road surfaces (R1,R2,R3 and R4)
• Based on careful measurement of cored samples
Road Surface Reflectance (2)
• Calculations of pavement luminance at many sites with the new surfaces (UK & France) using standard r-tables and measured r-tables of modern road surfaces show that the standard r-tables over-estimate the pavement luminance.
• E.g. an installation designed to provide a pavement luminance of 1.0cd/m2 with standard r-table actually gave a luminance of 0.7cd/m2
Road Surface Reflectance (3)
• This would lead to an increase in night accidents.
• To maintain the pavement luminance, there would be increased capital costs and an increase in energy costs of about 25%.
• Need to make widespread measurements of road surface types.
Road Surface Reflectance (4)
• Traditional measurement of road surface reflectance is by coring and lab. measurement-slow and sample is damaged
• Can now take advantage of CCD luminance meter to capture pavement luminance over a wide area, use installation data and I-tables to work backwards and calculate r-table in situ.
White Light & Mesopic Vision (1)
• The spectral sensitivity of human vision changes with adaptation level and with retinal eccentricity.
• Visual tasks of drivers change with the road environment resulting in differences in the importance of different areas of the retina
White Light & Mesopic Vision (2)
• The central 2o is dominated by cones and has the spectral sensitivity of the V() function.
• The periphery has a mesopic spectral sensitivity function depending on adaptation luminance and peripheral angle
White Light & Mesopic Vision (3)
• Division 1 has formed a TC to propose a model of mesopic vision.
• Division 4 TC 4-48 has a proposed terms of reference that will validate the Div 1 model in road lighting
White Light & Mesopic Vision (4)
• Latest Australian Road Lighting Standard:• For V category lighting-use manufacturers lamp
lumens for all lamp types• For P category lighting (except P4 &P5)-use
manufacturers lamp lumens for all lamp types• For P4 & P5- manufacturers lamp lumens should
be derated by x0.75 for HPS and x0.50 for LPS
White Light & Mesopic Vision (5)
• For any lighting, and especially for P category lighting, use sources with highest S/P ratio and CRI value compatible with costs, lamp mortality, lumen maintenance.