Article 25 — Outdoor Lighting and Road Glare
Purpose and Intent
Definitions
CUTOFF: A luminaire light distribution where the emission does not exceed 2.5 percent of the lamp lumens at an angle of 90 degrees above nadir, and does not exceed 10 percent at a vertical angle of 80 degrees above nadir. These emission values apply to all lateral angles around the installed luminaire.
FOOTCANDLE: A unit of measure for illuminance on a surface that is everywhere one foot from a point source of light of one candle, and equal to one lumen per square foot of area.
FULL CUTOFF: A luminaire light distribution where zero emission occurs at all angles of 90 degrees or greater above nadir, and the emission does not exceed 10 percent of total lamp lumens at a vertical angle or 80 degrees above nadir. These emission values apply to all lateral angles around the installed luminaire.
GLARE: The sensation produced within the visual field by luminance that is sufficiently greater than the luminance to which the eyes are adapted, causing annoyance, discomfort, or loss in visual performance and visibility.
Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance ILLUMINANCE: The quantity of light arriving at a surface divided by the area of the illuminated surface, measured in footcandles. Horizontal illuminance applies to a horizontal surface;
vertical illuminance applies to a vertical surface. Average illuminance is the level of illuminance over an entire illuminated target area. Maximum illuminance is the highest level of illuminance on any point within the entire area; minimum illuminance is the lowest level of illuminance on any point within the entire area.
ILLUMINANCE LEVELS: All illuminance levels and foot candles noted in this ordinance mean the maintained illuminance levels: the illuminance levels occurring just prior to lamp replacement and luminaire cleaning. The average illuminance level applies to an entire illuminated target area. Minimum and maximum illuminance levels apply to small areas within the entire illuminated target area. Unless otherwise noted, illuminance levels refer to horizontal illuminance levels.
LAMP: The component of an outdoor luminaire that produces light.
LIGHT TRESPASS: Unwanted light emitted beyond the boundaries of the property on which the luminaire is located, detrimentally affecting residents, vehicle operators and pedestrians, the natural environment, and astronomical observations.
LUMINAIRE (LIGHT FIXTURE): A complete fixed or movable lighting unit consisting of a lamp or lamps and ballasting (when applicable) together with the parts designed to distribute the light, to position and protect the lamps, and to connect the lamps to the power supply.
PERSON: Any individual, tenant, lessee, owner, or any commercial entity, including, but not limited to, a firm, business, partnership, association, joint venture, corporation, or organization, whether commercial, religious, fraternal, social or otherwise, or any agent thereof.
ROADWAY LIGHTING: Lighting that is specifically intended to illuminate roadways for automobiles, excluding the lighting intended to illuminate roadways only for pedestrians.
SECURITY LIGHTING: Continuous illumination of non-roadway territory when there is no/minimal nighttime activity by authorized individuals.
SEMI-CUTOFF: A luminaire light distribution where the emission does not numerically exceed 5 percent of the total at an angle of 90 degrees above nadir, and 20 percent at a vertical angle of 80 degrees above nadir. These values apply to all lateral angles around the installed luminaire.
SHIELDED: provided with internal and/or external shields, top and side visors, hoods, and internal louvers to limit glare, sky glow, and light trespass caused by emission from luminaires.
SKY GLOW. The brightening of the nighttime atmosphere by light emitted above the horizontal plane and by light reflected upward from illuminated surfaces, which reduces the visibility of astronomical objects.
UNIFORMITY RATIO: A higher level of illumination in relation to a lower level of illumination within a given target area. A value for either the maximum-to-minimum ratio or the average-to-minimum ratio may be required. For example, if the average-to-minimum uniformity ratio is 4:1 Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance for the given target area, the lowest level of illuminance is no less than 1 divided by 4 (25%) of the average level of illuminance.
Light Trespass
Directional luminaires such as floodlights, wall pack lights, and spotlights shall be aimed so that the center of the beam is not more than 62 degrees above nadir. Directional luminaires shall be shielded as needed for minimizing misdirected light.
Glare Control on Roadways
It shall be unlawful to place or maintain on private property any luminaire of such intensity or brilliance within the field of view of a driver so as to impair his/her vision upon the public roadway, or to interfere otherwise with the operation of a motor vehicle. Every reasonable effort shall be made to ensure that the brilliance of any luminaire less than ten (10) degrees from a passenger car driver’s line of sight; either along the roadway ahead or toward each traffic control device, sign, or signal; does not exceed the brilliance of a headlight on an oncoming passenger car whose extended center line lies 10 feet to the driver’s left, when the car is between 60 and 100 feet from the driver, and when the lowermost distribution of light from the headlight is in use.”
Luminaire Source Types Regulated
Mercury vapor, fluorescent, and metal halide lamps shall be installed in luminaires enclosed by acrylic, translucent material, or glass which filters out ultraviolet light; quartz glass does not qualify.
Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance
Restrictions of Various Outdoor Lighting Applications
Fast food facilities with customer seating of 40 or greater Entertainment theaters, assembly, sports arenas;
Major cultural or civic events Major league athletic events Truck or bus parking Automatic teller machines Fueling stations, except drive-under canopies and pump islands Automotive dealerships;
Residential complex parking
HIGH 0.9 4:1 MEDIUM 0.6 4:1 LOW 0.2 4:1 Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance
HIGH 2.0 3:1 MEDIUM 1.0 3:1 LOW 0.5 4:1
Illumination shall be provided by full cutoff luminaires, except for large areas, where luminaire supports inside the areas would restrict the function or compromise safety. Examples of such large areas include, but are not limited to, baseball, softball, soccer, football, and golf driving ranges. Shielded floodlights shall be used for these areas. Smaller areas, including tennis, volleyball, racquetball and handball courts, and swimming pools shall utilize full cutoff luminaires and shall conform to the requirements of this ordinance regarding light trespass. The average illuminance on ground shall not exceed 50 footcandles.
Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance
Table of Illuminance Levels and Uniformities for Car Dealerships Area Maximum Illuminance on Pavement (footcandles)
Maximum to Minimum Ratio Main Business Districts (major corridors)
Front Row (Adjacent to roadway), and feature 20 5:1 Other rows 10 10:1 Entrances 10 5:1 Driveways 3 10:1 Secondary Business Districts (or activity centers)
Front Row (Adjacent to roadway), and feature 10 5:1 Other rows 5 10:1 Entrances 5 5:1 Driveways 2 10:1
Exception: selected portions of a building may be illuminated from below, if the portions illuminated total less than half of the vertical face. The average illuminance shall not exceed 10 footcandles.
Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance
after dividing the total number by four, any remainder is counted as a whole number.
Red lights shall be used on towers only where required by the Federal Aviation Administration.
Prohibited Lights
Approved Materials and Methods
Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance
Permits and Development Plan Reviews
Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance
Petitions For Street Lighting in Subdivisions Containing Lots Which Are 1.1 Acres
Temporary Lighting Permits
Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance
business days from the date of submission of the request and notify the applicant in writing of his/her decision. The Community Development Director may grant one (1) renewal of the permit for an additional thirty (30) days if he/she finds that, because of an unanticipated change in circumstances, a renewal would be in the public interest. The Community Development Director is not authorized to grant more than one (1) temporary permit and one (1) renewal for a thirty (30) day period for the same property within one calendar year.
Variances
Nonconforming Uses
Exceptions
Cherokee County Zoning Ordinance Article 25 – Outdoor Lighting and Road Glare Ordinance