For the purposes of this chapter, terms used shall be defined as follows:
AVG:MIN OR AVERAGE:MINIMUM RATIO: A measurement of the uniformity of light distribution on a horizontal surface achieved by dividing the average light output on the paved surface by the minimum light output on that surface.
BACKSIDE SHIELD OR SHIELD: A device which is added or attached to a light fixture made from an opaque material which prevents light from being emitted in certain directions, and is commonly applied to prevent light from entering an adjacent property.
COLOR RENDITION INDEX OR CRI: A measure of the ability of a light source to reproduce the colors of various objects faithfully in comparison with an ideal or natural light source. A CRI of 100 is the maximum score and indicates a true replication of the color of an object in natural light conditions.
COLOR TEMPERATURE: A measurement in kelvin that indicates the hue of a specific type of light source for the purpose of comparing a proposed light source to natural daylight.
FIXTURE OR FIXTURE, LIGHT (Also Called LUMINAIRE): The complete lighting assembly (including the lamp(s), housing, ballasts, photocells, reflectors or refractors, lenses, sensors and shields) less the support assembly of pole, mounting bracket and base, consisting of one or more lamps together with the parts designed to distribute light, position and protect the lamp, and connect the lamp to a source of power. Light fixtures are evaluated for safety by Underwriters Laboratory and are "rated" to certain wattage limits, as affixed by a UL issued label. (See definition of UL Rating.)
FOOT-CANDLE (FC): A unit of measurement used to determine the amount of light incident on a surface, also known as "illuminance". One foot-candle (1 FC) is equivalent to one lumen evenly distributed over one square foot of surface area at a distance of one foot (1'). Foot-candle measurements can be taken with a handheld light meter.
FOOT-CANDLE LIGHT METER: A portable instrument which measures light levels in foot-candle (FC) units emitted from a light source on a horizontal or vertical surface.
FULL OR FULLY CUT OFF: A light fixture or luminaire designed, constructed and installed in such a manner that all light emitted from the fixture, either directly from the lamp(s) or a diffusing element, or indirectly by reflection or refraction from any part of the fixture, is projected below the horizontal plane through the fixture's lowest light emitting part.
GLARE: A visual disturbance produced by a direct view of a distinct light source within the visual field that is sufficiently brighter than the level to which the eyes are adapted to cause annoyance, discomfort, or loss in visual performance and visibility; blinding light.
ILLUMINANCE: Measure of incident light. The amount of light, evaluated according to its capacity to produce visual stimulation, that reaches a unit of surface area during a unit of time. It is measured in lux, or in foot-candles when evaluated on a square foot basis.
ILLUMINATING ENGINEERING SOCIETY OF NORTH AMERICA (IESNA OR IES): A nonprofit organization founded in 1906 with a mission to improve the lighted environment by bringing together engineers, lighting designers, consultants, lighting equipment manufacturers, sales professionals, electrical contractors, and academics to conduct research and promote best practices with the publication of reference guides for a variety of specific lighting applications.
LAMP: The source of light being emitted from a luminaire, such as a bulb.
LIGHT LEVEL: The illuminance as measured by a light meter as reported in photometry.
LIGHT OUTPUT: The amount of light which is emitted by a lamp or fixture.
LIGHT POLLUTION: Any unnecessary or adverse effect of artificial light including, but not limited to: glare, light trespass, excessive or unnecessary lighting, uplighting and sky glow; and any artificial light that unnecessarily diminishes the ability to view the night sky or is disruptive to the natural environment.
LIGHT SOURCE OR SOURCE: The light emitting part or parts of a light fixture, consisting of the lamp or lamps, and any transparent or translucent covering over the lamp, as well as any refractors, reflectors, prismatic lenses, mirrors, or diffusers which emit or transmit light.
LIGHT TRESPASS: Light that falls on neighboring properties or produces glare or distraction for observers away from the area for which the light is intended.
LIGHTING: Any or all parts of a luminaire that function to produce light, or light produced by a manmade source, including, but not limited to, electric lamps, gas lamps, and solar lamps.
LIGHTING, DECORATIVE: Lights that have an aesthetic purpose to illuminate the architectural features of a building, site or landscaping and produce generally low levels of light (less than 100 watts for traditional incandescent lights, or less than 1600 to 1800 lumens) including, but not limited to, "gooseneck" lights, sconce lights, recessed lighting in roof soffits, and silhouette lights.
LIGHTING, ESSENTIAL: Light that is used for a specified period of time which is necessary for a specific task or purpose while said task or purpose is actively being performed.
LIGHTING, EXCESSIVE: Illuminance which exceeds the amount of light which is permitted by the provisions, requirements and specifications contained herein.
LIGHTING, EXTERIOR: Temporary or permanent lighting that is installed, located or used in such a manner to cause light rays to shine outdoors. For the purposes of this chapter, fixtures which are located indoors, but which are intended to illuminate something outside are considered exterior lighting.
LIGHTING, HID (HIGH INTENSITY DISCHARGE): A high intensity discharge family of lighting that includes high pressure sodium, fluorescent, mercury vapor, metal halide and ceramic metal halide type bulbs. These types require a warmup time, usually require a ballast exclusive to the light source, and have a higher lumen output per watt than incandescent or halogen lamps.
LIGHTING, HOLIDAY: Temporary lighting installed in connection with a holiday or religious observances and intended to be removed thereafter.
LIGHTING INSTALLATION: The whole system of exterior lighting, including light poles, mounting systems, and lighting fixture elements (including light sources, such as incandescent, metal halide, mercury vapor lamps, and light emitting diodes (LED)) that provide illumination to a given building exterior, parking lot or other paved structure, or unpaved area.
LIGHTING INSTALLATION, NEW: A new lighting installation occurs in one or both of the following circumstances:
A. In a new development or redevelopment, where exterior lighting, including mounting poles, brackets, and fixtures are proposed to be affixed to or erected upon: 1) a new structure, including building, patio, canopy, sidewalk, parking lot or other paved area, or 2) an unpaved area;
B. When all exterior lighting, including mounting poles, brackets, and fixtures, affixed to or erected upon: 1) an existing structure, including building, patio, canopy, sidewalk, parking lot or other paved area, or 2) an unpaved area, are removed and replaced or renovated with new exterior lighting, including mounting poles, brackets, and fixtures.
LIGHTING, LANDSCAPE: Exterior lighting for the purpose of illuminating trees, shrubbery, plants, flowerbeds, waterways, gardens and nonstructural, manmade features, including, but not limited to, sculptures, fountains, trellises, statuaries, tree houses and other features.
LIGHTING, NONCONFORMING: Lighting which does not meet the provisions, requirements and specifications contained herein.
LIGHTING, NONESSENTIAL: Lighting which is unnecessary for pedestrian passage and not generally useful (e.g., aesthetic, decorative or landscape lighting). This includes lighting intended for a specific task or purpose when said task or purpose is not being actively performed (e.g., parking lot illumination and wall mounted perimeter lights after business hours).
LIGHTING, SPECIAL EVENT: Lighting approved by the village for use at a temporary special event.
LIGHTING, SPORTS: Light fixtures used to illuminate courts, arenas, riding arenas, fields, tracks and other recreational areas generally utilizing high light output fixtures, higher light levels and are mounted on higher than average freestanding poles.
LUMEN: The unit of measurement used to quantify the amount of light produced by a lamp or emitted from a fixture (as distinct from "watt" which is a measurement of the electrical power).
LUMINAIRE: See definition of Fixture Or Fixture, Light.
LUMINOUS FLUX: The power emitted from a source of electromagnetic radiation, such as a light bulb or light transmitting elements, in the form of visible light. Luminous flux is measured in lumens (lux) and is typically specified by the manufacturer for a given lamp or fixture. Typical luminous flux values for incandescent bulbs are 100W: 1550 lumens, 75W: 1080 lumens, 60W: 780 lumens and 40W: 450 lumens.
LUMINOUS TRANSMITTANCE: A measure of the amount of light that passes through a sample of transparent material, generally plastic. This measurement forms a basis for directly comparing the transparency of various grades and types of plastics. A haze meter and/or a recording spectrophotometer are used in the test. ASTM D-1003.
MAINTAINED FOOT-CANDLES: Illuminance of lighting fixtures adjusted for a maintenance factor accounting for dirt buildup and lamp output depreciation. The maintenance factor used in the design process to account for this depreciation cannot be lower than 0.64 of the initial lumen output for metal halide and mercury vapor lamps.
MOTION SENSOR: A sensor which causes a luminaire to become illuminated automatically upon the presence of motion or infrared radiation, or a combination thereof, within its field of view.
MOUNTING HEIGHT: The height above normal grade to the lowest light emitting part of an installed fixture.
PHOTOMETRY: A technical test report that indicates light distribution and performance of a fixture. A photometric plan may include candlepower distribution data, cutoff classification, foot-candle chart, etc., some of which are generally available directly from the manufacturer, and which may have been produced by an independent laboratory.
SEARCHLIGHT: Lighting installation, either ground or vehicle mounted, designed to project a high intensity beam of light that is typically used to sweep the sky for promotional purposes.
SHIELD OR SHIELDED: When applied to lighting, an opaque barrier which does not allow light to be transmitted in certain directions.
SKY GLOW: The brightening of the night sky or the overhead glow from artificial light that is directed upward or reflected off moisture and dust particles in the atmosphere, reducing the ability to view the natural night sky.
UL RATING: A reference to "Underwriters Laboratory", a commercial agency that certifies the maximum safe wattage for fixtures and other electrical devices. A UL label indicating the maximum safe wattage is affixed or imprinted on all light fixtures which are offered for sale.
UNIFORMITY RATIO: A ratio that describes uniformity of illuminance across an area.
UNSHIELDED: The luminaire only incorporates clear glass, which permits all light to escape. (Ord. 2013-19, 4-22-2013)