Robusts Indicators of the Spectral Environmental and Health Impact of Artificial Lighting Technologies

Transcription

1 Robusts Indicators of the Spectral Environmental and Health Impact of Artificial Lighting Technologies Johanne Roby, Martin Aubé Cégep de Sherbrooke, Québec, Canada

2 Artificial light at night increases every year. Evening are time more brightness Since 130 years: the brightness period has increased: 4h-7h/day people live more indoors under artificial lights Sherbrooke Downtown photo: Johanne Roby, sep 2013

3 Impact of Artificial Light on Nighttime s Integrity Consequence on: Ecosystem: fauna and flora; Health: disruption of biological clock (sleep, depression, obesity, cancer, etc.); Economy $$$ (waste of energy); Road Safety: glare effect; Starry sky. photos: Johanne Roby/Guillaume Poulin

4 Definition of light Photo: Johanne Roby, Banff, juillet 2013

5 Sun Spectral Composition The spectrum has some variability during the day in term of color and intensity Sun at noon

6 Role of the light in the photosynthesis Photosynthesis Action Spectrum Photosynthesis is a process where plant transform the solar light into organic compond Some reactions occurs during the light period and some during the night time Photosynthesis Action Spectrum Chlorophyl is the most important and commun in all vegetable species

7 Role of the light in biological processes Pineal Gland Hypothalamus Spinal Cord

8 Role of the light on the biological processes The blue light is very effective for the inhibition of the melatonin and stimulate awakening Pineal Gland Hypothalamus Blue Light light Spinal Cord Melatonin Suppression Action Spectrum

9 Human Eye Scotopic Spectral Sensitivity Light on Starry Sky

10 What is the difference between naturel and artificial light? Photo: Johanne Roby, Laurentides, juin 2013

11 Indoor Artificial Light versus Natural light LED Halo INC CFL

12 Outdoor Artificial Light versus Natural light HPS LED MH

13 What could we do to manage the lighting? 1- Changing the fixture help to manage the direction of light Ex: Cobrahead to Helios Reduction of the luminous flux to 1% above the horizon and of light to the sky 2- Diminution of te radiance power Less light to the night sky and save $$$ 3- Have some light periods closing time, motion detector, etc 4- Taking care about the color Help to protect the nighttime s integrity Photo : Guillaume Poulin

14 What could we do to manage the lighting? 1- Changing the fixture help to manage the direction of light Ex: Cobrahead to Helios Reduction of the luminous flux to 1% above the horizon and of light to the sky 2- Diminution of the radiance power Less light to the night sky and save $$$ 3- Have some light periods closing time, motion detector, etc 4- Taking care about the color Help to protect the nighttime s integrity Photo : Guillaume Poulin

15 The impact of The impact of artificial lighting on many biological processes is highly linked to the spectral content of the light Each biological process shows a different sensibility to light

16 Cool White LED Melatonine Suppression Action Spetrum

17 What is the composition of artificial light? How do we know and how could we know? photos: Johanne Roby/Guillaume Poulin

18 Developpment of 3 News Spectral Index Spectral Sensitivities To estimate the relative impact of lighting devices on melatonin suppression, photosynthesis process and star visibility To help authorities and population to manage the lighting MSI: Melatonin Suppression Index IPI: Induced Photosynthesis Index SLI: Star Light Index

19 Exemple for MSI (Melatonin Suppression Index) Lamp SPD Melatonin Suppression Action Spectrum Reference SPD (Sun) MSI = Sum ( Constant lumen spectrum x Melatonin suppression action spectrum ) Sum ( Constant lumen SOLAR spectrum x Melatonin suppression action spectrum )

20 Exemple for MSI (Melatonin Suppression Index) Lamp SPD Melatonin Suppression Action Spectrum Scale Value for Indices: 0 to 1 MSI 0 = no impact on melatonin suppression = use lamp in the evening 1 = strong impact on melatonin suppression = use lamp in the morning = be carefull for night Reference SPD (Sun) time s integrity IPI 0 = no impact on photosynthesis proceses 1 = strong impact on photosynthesis proceses MSI = Sum ( Constant lumen spectrum x Melatonin suppression action spectrum ) SLI 0 = no impact on the starry sky Sum ( Constant lumen SOLAR spectrum x Melatonin suppression action spectrum ) 1 = strong impact on starry sky = alterate the observation of the sky = our naturel Heritage

21 Impact compared to HPS Lamp Impact on Melatonin suppression (MSI) LPS Nichia Amber PC Ambre LED 2700K fil. HPS LED 5000KFil. INC LED2700K HALO FLT8 LED 4000K LED 5000K MH

22 Impact compared to HPS Lamp Impact on Induced Photosynthesis (IPI)

23 Impact compared to HPS Lamp Impact on Star Light (SLI) LPS PC Ambre Nichia Amber HPS LED 2700K fil. LED2700K LED 5000KFil. INC LED 4000K MH HALO FLT8 LED 5000K

24 Table 1. Spectral Index for street lighting devices CCT (K) MSI IPI SLI HPS LPS Metal Halide LED LED Lumiled PC Amber LED 4440K Filtered LED 2760K Filtered Ref. CIE D

25 Table 2. Spectral Index for domestic lighting devices CCT (K) MSI IPI SLI %Blue Halogen Incandescent Fluorescent T CFL CFL CFL LED LED ,2 LED

26 How do we know the content of the spectrum, by example: the blue content Is the CCT (Correlated Color Temperature) is suffisant?

27 Lamp Spectral Power Distrubution Database MSI, IPI, SLI, CCT % Blue = [ nm] x100 [ nm]

28 Table 3. CCT versus %bleu CCT (K) MSI IPI SLI %Blue Halogen Incandescent Fluorescent T CFL CFL CFL LED LED ,2 LED Lumiled PC Amber LED 4440K Filtered LED 2760K Filtered LPS HPS Metal Halide CIE D

29 Development of a pictogram for lighting devices Example for MSI

30 Conclusion We introduced three new indices to characterize lighting devices using the SPD These indices have been designed to allow a quick estimation of potential impact of different lamp spectrum on Melatonin Suppression, Photosynthesis, and Star visibility LPS, amber LEDs and LED 2700K filtered have a reduced potential impact on melatonin suppression in comparison to HPS. LPS, LED 5000K filtered and LED 2700K filtered show a lower impact on photosynthesis than HPS. Only LPS, amber LEDs and LED 2700K filtered are better or equivalent to HPS in order to restrict the impact on star visibility. amber LEDs and Metal Halide are the best to stimulate photosynthesis

31 Conclusion During daytime, if we want to have the highest spectral impact, we should favor lamp with high %Blue (for increased melatonin suppression) During evening, if we want to have the lowest spectral impact, we should favor lamp with low %Blue. The CCT is not sufficient to clearly show the spectral content of the light