THE PROBLEM OF LIGHT POLLUTION
Light pollution is the result of outdoor lighting that is not properly shielded, allowing light to shine into the eyes and the
night sky. People everywhere are losing the ability to see planets and stars in the night sky. The spectacular view of the
cosmos that has inspired science and art throughout history is disappearing. Even in rural environments such as Ivry-surle-Lac, uncontrolled outdoor lighting reduces the visibility of the stars, disturbs our appreciation of the night landscape,
and harms our ecosystems, affecting the foraging, mating and migratory behaviors of nocturnal wildlife. Excessive
outdoor lighting also wastes energy and money!
WASTE: In 2002, approximately 30 percent of all outdoor lighting was wasted due to poor design. Unshielded fixtures that
allow light to escape upward or provide more light than is required are major contributors to this inefficiency.
WHAT YOU CAN DO:
PROTECT IVRY’S NIGHT SKY WITH GOOD LIGHTING PRACTICES AND SET AN EXAMPLE FOR OTHERS!
Controlled Lighting
Courtesy Royal Astronomical Society of Canada
Dark Site with No Control of Lighting
http://www.rasc.ca/lpa/guidelines
SHORTER OUTDOOR LIGHTING HOURS
• Use timers, dimmers, and motion sensors in all outdoor lighting
• In general, turn off outdoor lights by 10pm
• Make sure all outdoor lights are off when you leave for extended periods
BETTER OUTDOOR LIGHTING
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Install lighting only where it is needed
Install efficient, modestly bright lighting
Always direct lighting toward the ground
Use fully shielded fixtures
Example of shielded fixture
http://www.homedepot.ca/product/dark-sky-collection-6-in-1-lightoutdoor-wall-mount-in-bronze/958971
SHIELDED INDOOR LIGHTING
• Draw opaque blinds or curtains at night to shield others from indoor lighting
• Use ‘shielded’ interior fixtures at lakeside windows
DARK SKY COMPLIANCE AND SAFETY GO HAND IN
HAND!
• Bright light does not increase safety. Ironically,
too much lighting can threaten security by
compromising vision with glare and casting
harsh shadows where criminals can hide.
• Lights left on after normal sleeping hours are
an advertisement that no one is home.
• The key to being safe is having fully shaded
uniform lighting that does not infringe on the
sky, on a timer or sensor, that allows the eye to
adjust to naturally dark conditions for maximum
visibility.
Additional resources:
http://darksky.org/
http://www.rasc.ca/lpa
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2627884/
This information is provided by the AALME Environment Committee
LIGHT POLLUTION TERMINOLOGY
Glare – excessive brightness that
causes visual discomfort
Urban sky glow – the brightening of
the night sky over inhabited areas
Light trespass – light falling where it
is not intended, wanted, or needed
Clutter – bright, confusing, and
excessive groupings of light sources