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With the proliferation of poorly written local ordinances, the International Dark Sky Association (IDA) and the Illuminating Engineering Society (IES) have collaborated arduously on the development of a joint Model Lighting Ordinance that can be used by communities to limit light pollution while maintaining good lighting practices.

Sky Glow or Light Pollution - a condition where the night sky is illuminated when upwardly directed light reflects off particles in the atmosphere, such as moisture, dust, or smog.


International Dark-Sky Association.


Illuminating Engineering Society of North America.

This regulation is about "Light pollution", the orange glow above the city from all the lights. The reason for this is over-lighting of various places in the city such as, malls, parking lots, and residential neighborhoods.Thisproblem is from poor and inefficient lighting designs, which is not regulated in major cities and towns, including airports.


Dark sky regulated lights fixtures are ones that cut glare and prevent light to trespass that will reduce sky glow and thus will not have wasted energy. Essentially glare, light trespass and sky glow are components of energy being wasted for outdoor lighting.

What is light trespass or Spill Light: When someone’s light is aimed at you. An example is your neighbors spot light shines through your window. Under the dark sky regulation the lights must be aimed down or they must have a hood so the light is centralized to a specific spot, or motion sensors. This also affects the wildlife and throws off the ecological community.

What is glare: Glare affects motorist at night when your eyes are adjusted to the darkness. When a car passes with their lights on and will cause the motorist not able to see for a moment. This is not restricted to just vehicles at night but businesses that leave their lights on. Resolve this by aiming lights down or using a visor to dissipate the light from people’s eyes simply the excessive brightness experienced by looking directly into a light fixture.

Dark Sky Regulated Lights: "Starlight, star bright, first star I see tonight!!" For those living in American suburbia, this little rhyme has lost a lot of its meaning. To seriously get to see what one has been missing. Ask any sailor that knows - there advice will be for a moonless night. An observatory with endless views out to sea by day; endless views of the stars at night - horizon to horizon. With the advent of a growing population, needs for lighting have increased tenfold in the past 25 years. Lighting affects every part of our daily lives. Far removed from the days where simple firelight extended our working hours a bit past sunset, we now have had the ability to create a 24 hour workday with every kind of illumination available to suit a task. Streetlights, malls, Las Vegas, outdoor lights, pool lights, and house lights etc., all of these have an effect on our daily environment.

What is light pollution and why is it important? It is the pale-yellow foggy quality in our skies that often blocks the view of stars and other celestial bodies. Light pollution affects us every day in ways that we have become accustomed to. It is not limited just to big cities, from outer space it is common to see millions of webs of light streaming across the continents, even areas not lit! It is a concern beyond astronomers and dark sky enthusiasts. You experience light pollution when you can’t sleep at night because of your neighbor’s outdoor porch light, when a driver’s headlights are too intense for your dark adjusted eyes and the glare becomes blinding, and when all of the wild life from your rural area have vanished without a trace. You even experience light pollution when your children ask you where the big dipper is and you cannot locate it. All that light up in the sky is wasted unnecessary energy. A light should be regulated to its specific task. It is often forgotten that light refracts and that it comes in different wavelengths and intensities. Although you may only see one beam, light is actually refracted from nearly any solid object that comes into contact with it. An over-lit shopping center can easily direct that familiar yellow haze to places it was never intentioned to light.

So what's the Problem? The big problem is still the lack of awareness of the issues, the problem, and the common sense solutions. Education is a big part of fixing the problem. The second problem is apathy. Even with awareness, action is needed. Some consider it too big a problem, others that it is not important enough. Talk to your neighbors and your local government officials. Light Pollution can be corrected one town at a time. There are many neighborhood associations and community leaders that are trying to preserve our natural dark skies, especially in areas that are near and around wildlife and state parks. Many communities are taking their skies back by passing legislation to regulate the use and design of "wasteful lighting".

Such lighting is often referred to as Dark Sky Compliant, Cut - Off Lighting, Friendly Lighting or Good Neighbor Lighting, Dark Sky Regulated. These names all refer to fixtures that are especially designed to reduce upward light reflection, glare, trespassing light, inefficient energy uses, and urban glow. The lighting industry has responded by creating light fixtures that consumers can easily install with little modification to their existing systems. This response has allowed dark sky compliance to be more accessible to the general public.

By proactively choosing to use environmentally sound fixtures, everyone can make an impact. Simple technologies and modifications to outdoor fixtures like motion-sensor activated flood lights, timers; even a hooded light can immensely help the situation. Even using focused lights in lower wattages can help. It is better to think of light as an accent to the environment you are in, not the environment itself. If each person takes their part to be responsible for their space the possibilities are endless. There is a greater chance that future generations will be able to sing "Twinkle, Twinkle Little Star" to an actual star.

What else can I do to be more energy efficient? The best and most happy consumer is the informed consumer. Do what you can to research energy efficient solutions available in your community. Many communities now issue rebates or other incentives including free upgrades to switch over to more energy efficient fixtures. By using small modifications such as timers, motion-sensors, photo-cells as well as solar energy you can do your part to help the environment. Simply shutting off a light when you leave the room makes a difference if a million people do it. Especially in the summer and winter months, there are high demands on electricity. You can do small things like installing a ceiling fan and adjusting the blade pitch to a reverse flow during the winter to distribute "trapped heat" from the ceiling. In the summer, invest in wall units and cool only the "used" areas of the house.

Attractive lanterns offer traditional styling with modern, environmentally friendly features. Specially designed to reduce light pollution, these wall lanterns offer night sky friendly functionality in a traditional lantern style.

Environmentally friendly benefits include:

  • Improved visibility
  • Reduced light pollution
  • Reduced glare
  • Reduced light trespass
  • Reduced energy consumption

International Dark-Sky Association (IDA) www.darksky.org


These brochures practical guides are designed for public use, and are free of charge. Topics covered are on four major areas of light pollution: wildlife, energy, safety, and human health. The practical guides are a compilation of numerous information sheets and include reference material, providing an excellent source for use at public meetings or neighborhood association meetings.

You must have Acrobat® Reader® installed to veiw the PDF files. It is available for free download by clicking here, if it is not already on your computer.

The materials are provided in full color or black and white to meet your printing needs. All are sized on standard letter (8.5" x 11") paper; however this should not prevent you from printing the materials on alternative sizes, such as A4. To do so, simply select "Fit to Printable Area" from the drop down menu in your standard print screen.

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