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Recommended Lighting Zones

Lighting zones reflect the base (or ambient) light levels desired by a community. The use of lighting zones (LZ) was originally developed by the International Commission on Illumination (CIE) and appeared first in the US in IES Recommended Practice for Exterior Environmental Lighting, RP-33-99. To learn more read about our Model Lighting Ordinance.

IDA Suggested Lighting Zones for Codes and Ordinances

At this time, IDA recommends the use of five (5) outdoor lighting zones. The following are suggested criteria for the appropriate wording of the proposed lighting zones.

  • LZ0: No ambient lighting
    Areas where the natural environment will be seriously and adversely affected by lighting. Impacts include distrubing the biological cycles of flora and fauna and/or detracting from human enjoyment and appreciation of the natural environment. Human activity is subordinate in importance to nature. The vision of human residents and users is adapted to total darkness, and they expect to see little or no lighting. When not needed, lighting should be extinguished.
  • LZ1: Low ambient lighting
    Areas where lighting might adversely affect flora and fauna or disturb the character of the area. The vision of human residents and users is adapted to low light levels. Lighting may be used for safety, security and/or convenience but it is not necessarily uniform or continuous. After curfew, most lighting should be extinguished or reduced as activity levels decline.
  • LZ2: Moderate ambient lighting
    Areas of human activity where the vision of human residents and users is adapted to moderate light levels. Lighting may typically be used for safety, security and/or convenience but it is not necessarily uniform or continuous. After curfew, lighting may be extinguished or reduced as activity levels decline.
  • LZ3: Moderately high ambient lighting
    Areas of human activity where the vision of human residents and users is adapted to moderately high light levels. Lighting is generally desired for safety, security and/or convenience and it is often uniform and/or continuous. After curfew, lighting may be extinguished or reduced in most areas as activity levels decline.
  • LZ4: High ambient lighting
    Areas of human activity where the vision of human residents and users is adapted to high light levels. Lighting is generally considered necessary for safety, security and/or convenienc