Select Outdoor Lights So They:

Are Cost Effective
The cost of lighting is not only the initial cost of the fixture and installation but the annual operating cost.
For example, a fixture and five year operating cost of a Quartz floodlight may be over $400 while a
comparable compact fluorescent floodlight is just over $100.  Turn on outdoor lights only when needed
and consider using motion sensors properly aimed and adjusted to turn them on and off.

Minimize Glare & Excessive Brightness
Glare occurs when you can see light rays directly radiating towards you from the fixture or bulb.
It can hamper vision of drivers, pedestrians,  and cyclists which often creates a hazard.  It can take
the human eye over 10 minutes at night to adjust to normal conditions after being in an excessively
bright area (like under a gas station canopy).

Eliminate Sky Glow
Light fixtures that allow light to travel outward and/or upward create Sky Glow.  This is a waste
of light and energy and very harmful to night sky viewing (amateur, professional, and casual observers
of the stars and planets).  It is also harmful to migrating birds and many other animals.

Eliminate Light Trespass
Light that travels outward (horizontal) leaves your property and shines somewhere else. This can be very
annoying and offensive to a neighbor often many blocks away.  All lighting should be directed downward
to stay on your property by using fixtures with "full cut off" shields (the source of the light should not be visible
when standing about 20 feet away).

Conform to Local Lighting Ordinances
Many States, Counties, and Cities (including Arizona, Pima County, Tucson/Oro Valley and most of the
other Cities in Arizona) have laws pertaining to outdoor light pollution.