obtrusive lighting
DESCRIPTION
OBTRUSIVE LIGHTING. Upward reflected light. Upward direct light. Obtrusive light. Direct glare. R-TECH 1. Definitions. SKY GLOW. SPILL LIGHT. Area to be lit. Three phenomena are related to light control of luminaires and their installation. Glare. Obtrusive light. - PowerPoint PPT PresentationTRANSCRIPT
OBTRUSIVE LIGHTING
Direct glare
SPILL LIGHT
SKY GLOW
Obtrusive light
Area to be lit
R-TECH 1
Upward direct light
Upwa
rd re
flecte
d ligh
t
Definitions
Three phenomena are related to light control of luminaires and their installation
Glare
All are the result of waste of energy
Obtrusive light Sky glow
Glare
the most critical problem
As it has to do with safety of drivers and pedestrians
Threshold Increment TI limitation for road
lighting Glare Rating
GR limitation for large area
1°E
Disability glare - TI
(CIE 140)
K E2
andLv = TI = 65Lv
LR0.8
10% or 15%
Glare Rating - GR
(CIE 112)
GR = 27 + 24 lg (Lvl / Lve 0.9)
With Lvl = veiling luminance produced by luminaires
Lve = veiling luminance produced by environment
and Lve = 0.0355 Lav
with Lav = EH.
Glare Ratio GR
Unbearable
Disturbing
90
80
70
60
Just admissible 50
Noticeable
Unnoticeable
40302010
Glare Rating limitation
Glare control
At design stage :
On site :
Calculation of TI or GR
Cannot be measured
Obtrusive light
Light falling out of the area of interest ,
causing disturbances or reducing confort
By – over lighting
– stray light
– bad wave length
CIE zoning system (CIE Nr. 126)
Zone rating
Description
E1 Areas with intrinsically dark lanscapes
E2 Areas of ’’low district brightness ’’
E3 Areas of ’’middle district brightness ’’
E4 Areas of ’’high district brightness ’’
CIE zoning system Application of CIE Nr. 150
Zone rating
Surrounding Examples
E1 Natural National parks or protected sites
E2 Rural Industrial or residential rural areas
E3 Suburban Industrial or residential suburbs
E4 Urban Town centres and commercial areas
CIE zoning system
Light
Technical parameter
Application conditions
Environmental Zones
E1 E2 E3 E4
Illuminance
In vertical
Plane (Ev)
Pre-curfew : 2 lux 5 lux 10 lux 25 lux
Post-curfew : 0* lux 1 lux 2 lux 5 lux
Maximum values of EV on properties - CIE 150
CIE zoning system
Light
Technical parameter
Application conditions
Environmental Zones
E1 E2 E3 E4
Luminous
Intensity
Emitted by
Luminaires (I)
Pre-curfew : 2500 cd 7500 cd 10000 cd 25000 cd
Post-curfew
Hours :0 cd* 500 cd 1000 cd 2500 cd
Maximum values of I (cd) in specific directions - CIE 150
Limitation of effects on transport system - CIE 150
Light Technical Parameter
Road Classification
No road lighting
M5 M4 / M3 M2 / M1
Threshold Increment TI
15% based on adaptation luminance of
0.1 cd/m²
15% based on adaptation luminance of
1 cd/m²
15% based on adaptation luminance of
2 cd/m²
15% based on adaptation luminance of
5 cd/m²
CIE zoning system
Limitation of effects on over lit building and signs CIE 150
CIE zoning system
Parameter
Application
Conditions
Environmental Zones
E1 E2 E3 E4
BuildingFacadeLuminance(Lb )
0 cd/m² 5 cd/m² 10 cd/m² 25 cd/m²
SignLuminance
(Ls )50 cd/m²
400 cd/m²
500 cd/m²
1000 cd/m²
EAV x
EAV x
or LAV
SKY GLOW
Definition :
Brightening of night sky
resulting from reflection of radiations
scattered from the constituents of the
atmosphere in direction of observation
Sky glowSky glow
SKY GLOW
SKY GLOW
- Artificial lighting installations
direct upward light
upward reflected light
- Headlights of vehicules
- Atmosphere pollution
- Atmosphere humidity
- Clouds
- Radiation from celestian sources
Many factors contribute to sky glow
SKY GLOW
advertising signs ;
area lighting of sales areas, parking lots, etc..
floodlighting of buildings, discos and monuments
lighting of billoards ;
lighting of greenhouses ;
lighting of industrial site, airports and buiding sites
lighting of sports facilites
road and street lighting
Stray light due to artificial lighting
SKY GLOW
First approach : CIE 126 (1997)
SKY GLOW
CIE Zoning system - CIE 126
Zone rating ULOR inst (%) Astronomical acivities
E1 0Observatories of (inter)national
standing
E2 0 – 5 Postgraduate and academic studies
E3 0 - 15Undergraduate studies, amateur
observation
E4 0 - 25 Casual sky viewing
SKY GLOWMinimum distance (in km) between zone borderlines and ref. point
Zone rating of reference
point
Zone rating surrounding zones distance (km) tobordeline of surrounding zones
E1 – E2 E2 – E3 E3 – E4
E1 1 10 100
E2 1 100
E3 1
E4 No limits
Definitions
ULOR = % of flux of the lamp(s)
of a luminaire above horizontal
DLOR = % of flux of the lamp(s)
of a luminaire below horizontal
= DLOR + ULOR
Definitions
ULR = % of flux of a luminaireabove horizontal
UWLRULOR inst
ULR = DLOR + ULOR
ULOR
CIE recommandation for thelimitation of sky glow
Zone rating ULORinst (%)
E1 0
E2 0 – 5
E3 0 – 15
E4 0 - 25
Sky glow limitation
Second (our) approach :
Limitation of UPF ( UPward Flux )
DLOR
ULOR
(DLOR-K)1
2 2
Where = ULOR + DLOR, i.e. = ULOR + K + (DLOR-K)
K
).(. 21)(_ KDLORKULORLpotentialtotalupwards
FLUX OF THE LAMP DIRECT FLUX
UPWARDS
REFLECTION ON THE ROAD
REFLECTION ON SURROUNDINGS
Then, upwards (potential)= lamp x % of rays going upwards
).(. 21)(_ KDLORKULORLpotentialtotalupwards
Depends on :
E resquested by
standards
S surface to be lit :
political
decision The nature of the surfaces to be lit and the surroundings: we have very little influence on this choice
These are the luminaire features,
where we can have a say
How can we influence the upwards (potential) ?
Finding the good compromise between:
Reducing ULOR
Increasing K (as close as possible to DLOR)
Optimizing the E/L ratio for road lighting installations
Getting the best possible photometry
But being aware that there is no magic recipe (due to the uncertainty on the surfaces reflection
properties, especially on the surroundings’)
In many occasions, low depth glasses (Onyx, Saphir and
MC low deeps, Image,…) are the best photometrical
compromise
But flat glasses are good enough a lot of times too and...
USE OF FLAT GLASS IS WIDELY ACCEPTED BY ASTRONOMERS
But we must not forget that for some , deep
protectors (that have higher ULOR) and even refractors
are a less “polluting” solution than the others!!!
Road lighting applications
High pollution
Reducing ULOR
Flat glass at 0°?
Curved glass protector isoften the best solution
Recommendations for other installation
Do not “over” light
Direct light downwards
Keep beam below 70°
Take care with location and height of poles
70° <70°
Lower aiming
possible
Use of narrow beam floodlight possible
Higher aiming
necessary
Use of wider beam floodlight
may be necessary
(a) Higher mounting heights – less spill and glare
(b) Lower mounting heights – more spill light and glare
Floodlighting
Use asymetric light distribution
Focal
Neos 3
Citea
Louvers and shades to be used adequately
Recommendations for all lighting installations
Use high IP luminaires
Realise the most efficient lighting solution
in long term condition
Thank you for your attention