Three Types of Light Pollution

Three Types of Light Pollution

What's the problem?	Why should I care?	What can I do?
Glare Glare is light striking your eye directly from the source. A veil of light across your field of view reduces the contrast between objects--you can't see as well in the stark brightness.	For motorist and pedestrian safety, drivers need to discern objects at night. The two critical road signs at this intersection (left) are difficult to see because the eyes are overwhelmed by direct light, creating a hazard. Glare hinders true security by creating extreme shadows, offering refuge to criminals in spite of the bright lights. Glare can be discomforting, disabling, or blinding. As we age, the effect--and its impact on our lives at night--becomes worse.	Aim adjustable lights downward so they are level with the horizon. Purchase dark-sky friendly fixtures that have the light bulb tucked into the luminaire housing, not exposed to the eye. Install only light fixtures that are fully shielded. Install security lights with motion detectors for greater security. With lighted signs, request lighter text and logos/graphics against a dark, opaque background.

Spillover *Spillover* is light that extends beyond the targeted object. This includes light trespass, which extends beyond property lines.	Light that is broadcast well beyond the intended area is wasted--an unnecessary loss of money. Light that encroaches upon the property of others, such as into bedroom windows, is a personal infringement. Neighbors are entitled not to have your bright lights shining into their personal space. Roadway light that spills into adjacent properties represents a waste of tax dollars.	Contain floodlights with clip-on visors and aim the fixtures downward. Install fully shielded lights, and do not place light mounts where the light crosses property lines. Save money by lessening the light output (in lumens) of existing fixtures.

Skyglow Sky glow is the garish hue seen overhead from artificial light scattering in the atmosphere. The reflected light masks the background stars and creates a pallid-looking sky.	You could readily save the tax dollars spent on lighting the clouds. Light sent skyward is a waste of that light (<2% of the cost) plus the additional energy loss (~98% of the cost) that went into producing the light pollution. Our children are losing the heritage of the night sky. Most of them are unable to see the Milky Way galaxy or other dark sky wonders. Nocturnal animals are disrupted by the abnormal night lighting. Some studies suggest human health is negatively affected because of disrupted circadian rhythms due to light pollution.	Install simple visors over existing lights and and purchase fully shielded fixtures. Find a less offensive way to express yourself than through outdoor vanity lights (right) and landscape lighting. Ask your elected officials to select public lighting fixtures that don't waste your tax dollars skyward. Help reclaim the vast public space overhead. Aim billboard lights down instead of up.

For sources of good lights, see solutions.htm.

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Copyright ©2009 Chuck Bueter. All rights reserved.