Do We Really Need Night Lighting?
A hundred years ago, the Cincinnati Astronomical Society moved their observatory from Mt. Adams to the city perimeter, to escape the city lights. Today, suburban 24-hour lighting has caught up to them. The society is one of several such groups who have set up observation stations in Adams County, where it’s still dark enough to see the stars at night.
It’s a priceless, non-renewable resource, to see the stars. Lighting the heavens or your neighbor’s property is needless waste. Modern society uses outdoor lighting for a variety of needs, including safety and commerce. To minimize any negative effects, lighting can be used only when needed, only light the area that needs it, be no brighter than necessary, and be fully shielded (pointing downward). Most outdoor lighting sold today has designed-in waste and light scatter; it takes special attention to find well-designed fixtures. A good way to tell which is which is to ask yourself; can I see the bulb? If so, the fixture will scatter unnecessary light and actually reduce your ability to see at night.
Many people believe that more and brighter lighting makes us safer, but there is no conclusive evidence. We’ve all been blinded by high beams from oncoming cars. There’s a moment of panic when you can’t see where you’re going, and it takes time for your eyes to adjust once the brightness is gone. Outdoor lighting has the same effect on your eyes; seeing directly into the light source reduces your night vision. This is one way your “security lights” can affect your neighbors without you realizing it.
A dark sky does not necessarily mean a dark ground. Smart lighting that directs light where it is needed creates a balance between safety and starlight. Visibility should always be the goal. Glare from bright, unshielded lights actually decreases safety because it shines into our eyes and constricts our pupils. This can be blinding, making it harder for our eyes to adjust to low-light conditions.
The fact is that much outdoor lighting used at night is inefficient, overly bright, poorly targeted, improperly shielded, and, in many cases, completely unnecessary. This light, and the electricity used to create it, is being wasted by spilling it into the sky, rather than focusing it on to the actual objects and areas that people want illuminated. Each of us can take steps to combat unnecessary light scatter, once we understand the problem.
Groups like the International Dark Sky Association have many valuable resources to help you. Their “Fixture Seal of Approval” program makes it easy for you to find the right fixtures. The program certifies dark sky friendly outdoor lighting; fixtures that are fully shielded and have low color temperature. You can then request the recommended lighting from your local electrical supply store.
Steve Boehme is a landscape designer/installer specializing in landscape “makeovers”. “Let’s Grow” is published weekly; column archives are on the “Garden Advice” page at www.goodseedfarm.com. For more information is available at www.goodseedfarm.com or call GoodSeed Farm Landscapes at (937) 587-7021.