Light Pollution Reduction
Outdoor lighting is important for safety, lighting passages between buildings and sidewalks, parking lots and roadways. However, poorly designed exterior lighting can add to nighttime light pollution which can interfere with nocturnal ecology, reduce observation of night skies (aka Sky Glow), cause roadway glare and jeopardize relationships with neighbors by creating light trespass.
Properly designed lighting systems can promote an appreciation for a place at night. Careful selection of fixture types and wattage and controlling the lighting during off hours or curfew times can avoid light pollution, maintain safety and enhance the public image of a company.
Properly designed lighting systems can promote an appreciation for a place at night. Careful selection of fixture types and wattage and controlling the lighting during off hours or curfew times can avoid light pollution, maintain safety and enhance the public image of a company.
The intent of light pollution reduction is to:
Interior
Exterior
- Minimize light trespass from the building and site
- Reduce sky glow to increase night sky access
- Improve nighttime visibility through glare reduction
- Reduce development impact on nocturnal environments
Interior
- Utilize indirect interior lighting or automated non-emergency lighting shutoff controls
- Shut off non-emergency lighting:
Exterior
- Design site lighting with computer model
- Use computer modeling for proper selection and location of fixture types
- Accurate control of illumination levels, particularly important for maintaining required lighting densities per ASHRAE 90.1 and light trespass at the project property lines
- Use computer modeling for proper selection and location of fixture types
- Only light areas required for safety and comfort
- Shut off or reduce lighting levels for non-essential lighting such as building facade and landscaping lighting
- Use full cutoff light fixtures, low angle spot lights and low reflectance surfaces
- Full cutoff light fixtures prevent wasteful uplighting above a horizontal plane, reduces glare and helps prevent light trespass
- Low angle spot lights help reduce glare, lighting unnecessary surfaces and wasting energy lighting the sky
- Low reflectance surfaces reduces light reflectance and trespass
- Full cutoff light fixtures prevent wasteful uplighting above a horizontal plane, reduces glare and helps prevent light trespass
- Classify project lighting zone and comply accordingly with the requirements of IESNA RP-33
- LZ1 - Dark (park and rural settings)
- LZ2 - Low (residential areas and neighborhood business districts)
- LZ3 - Medium (commercial/industrial and high density residential)
- LZ4 - High (major city centers and entertainment districts)
- School sports fields are excluded from requirements, but must have automatic shutoffs
- LZ1 - Dark (park and rural settings)
