[Added 4-11-2011 by Ord. No. 2169]
The following words and terms, when used within this chapter, shall have the following meanings:
ARTIFICIAL LIGHT SOURCEShall mean a man-made thing or object from which light originates (ex: an electrically-powered lamp).
CANDELA (FORMERLY, CANDLE)Shall mean the "SI" unit of luminous intensity, one candela describes a luminous intensity of one lumen per steradian.
CUTOFF LUMINAIREShall mean an IESNA classification describing a luminaire that emits at least 97.5% of its light output below vertical angles of 90° from nadir at the lowest light-emitting point of its light source and not more than 10% of its light output above angles greater than 80° from nadir at the lowest point of its light source.
DEVELOPED PROPERTYShall mean real property which has been altered from its natural state by the lawful addition of improvements such as buildings, structures, impervious area, etc.
DOWNWARD-AIMED LIGHT FIXTUREShall mean a light fixture aimed no higher than 60° above nadir from the lowest light-emitting point of its light source.
ENERGYShall mean the ability to do work.
EXTERNALLY ILLUMINATED SIGNShall mean a sign any face of which is illuminated by one or more artificial light sources located between the reader and the sign face and directed toward the sign face.
FLOODLIGHTShall mean an unshielded artificial light source or lamp designed to produce relatively uniform illumination across a broad area.
FULL CUTOFF LUMINAIREShall mean an IESNA classification describing a luminaire that emits 0% of its light output above angles greater than 90° from nadir at the lowest light-emitting point of its light source and not more than 10% of its light output above angles greater than 80° from nadir at the lowest point of its light source.
FULLY SHIELDED LUMINAIREShall mean a luminaire that emits no direct uplight (i.e., 100% of its light output is below a vertical angle of 90° from nadir at the lowest light-emitting point of the light source).
GLAREShall mean illuminance within the visual field of a human eye which is sufficiently greater than the intensity of illuminance to which the eye is adapted that it causes annoyance, discomfort, reduced vision and/or momentary blindness.
HORIZONTAL ILLUMINANCEShall mean the measure, in footcandles, of the total amount of visible light incident upon (i.e. illuminating) a point within a horizontal surface taken through the sensor of a light meter held horizontally upon the point. Within this Ordinance, standards for "horizontal illuminance" levels shall be interpreted as "horizontal illuminance measured at ground level" unless specifically stated otherwise.
IESNAShall mean abbreviation for "Illuminating Engineering Society of North America" (also known as "IES") which has a membership consisting of architects, engineers, designers, educators, students, contractors, manufacturers, and scientists and which provides technical guidelines, standards, professional journals, and educational training forums related to the practice of lighting.
ILLUMINANCEShall mean the total amount (density) of visible light incident upon (i.e. illuminating) a point of a surface from all directions above the surface measured in footcandles (note: the "surface" may be a part, or all, of a physical object or an imaginary plane).
INTERNALLY ILLUMINATED SIGNShall mean a sign any face of which is opaque and illuminated by one or more artificial light sources enclosed entirely within the sign cabinet and not directly visible from any point outside of the sign cabinet.
LAMPShall mean a radiant light source; the replaceable, electrically-powered light source of a light fixture.
LIGHT(see "Visible Light").
LIGHT FIXTUREShall mean an electrically powered lighting device consisting of a lamp, a lamp holder, an electrical ballast (if necessary), and the means for connecting the device to an electrical power source.
LIGHT SOURCEShall mean a thing or object from which light originates (note: an object that reflects light originating from a different object is not a light source).
LIGHT SPILLAGEShall mean light projected onto a property from an artificial light source not located upon that property.
LIGHT TRESPASSShall mean light spillage not compliant with the requirements of this chapter.
LIGHTINGShall mean the celiberate utilization of one or more artificial light sources to achieve an aesthetic or intended effect.
LUMEN (ABBREVIATED IM)Shall mean a unit of measurement of luminous flux (i.e., of the total amount of light emitted in all directions per unit time) within the International System of Units.
LUMINAIREShall mean a self-contained lighting system component containing a light fixture and, as necessary, an outer shell or housing, a mirror or reflector, an aperture, a lens or refractor and a mounting bracket or pole socket; within this chapter, the term "luminaire" shall refer to outdoor lighting luminaires unless otherwise stated.
LUMINOUS FLUXShall mean the perceived rate of flow of light from a lamp or light source; measurements of luminous flux reflect the variability in sensitivities of the human eye to different wavelengths of light.
LUMINOUS INTENSITYShall mean the total luminous flux within a given solid angle, in units of candelas, or lumens per steradian.
MOUNTING HEIGHTShall mean the distance, measured along the nadir, between the lowest light-emitting point of the light source within a luminaire or light fixture and the ground surface below.
NADIRShall mean the nadir at a particular point is the local vertically downward direction from that point (i.e., the nadir at a point is directed from that point along the line of force of the earth's gravity).
OUTDOOR LIGHTINGShall mean the lighting of areas exterior to the walls of enclosed buildings and/or within structures having open or partially open walls such as canopies, porte cocheres, pavilions, gazebos, etc.
POWERShall mean the rate at which energy is utilized used by a device to produce useful work (also called input power or active power); in lighting, it is the system input power (in watts) for a lamp/ballast combination.
PROPERTYShall mean a tract of land depicted upon the Municipal Tax Map as one or more lots and which is assessed as a single tax parcel by the Municipal Tax Assessor.
SEARCHLIGHTShall mean aimable light fixture designed for outdoor use containing an artificial light source having a power rating in excess of 500 watts and reflectors designed to produce a narrowly conical, high intensity light beam visible for a relatively long distance but generally unsuitable for illumination of streets, driveways, parking fields, pedestrian paths, flags, architectural features, site improvements, etc.
SHIELDED LIGHT SOURCEShall mean a light source which is positioned and/or equipped with light shielding devices so that it is not directly visible to any person distant 10 feet or more from the light source, or from any point upon or outside of the property boundary.
SHIELDINGShall mean the blocking of an electromagnetic field with a metallic substance in a manner that reduces electromagnetic waves radiated; electronic components, wires, lamps, and similar devices can all be shielded.
SOLID ANGLEShall mean a conical volume of space defined by a point (the vertex of the solid angle), a sphere centered upon the vertex point, an area segment upon the surface of the sphere and the collection of rays which begin at the center point of the sphere and which pass through the points of the perimeter of the area segment upon the surface of the sphere.
SPOTLIGHTShall mean an unshielded artificial light source or lamp designed to produce a narrow, well-directed beam of light upon a small area.
STERADIAN (ABBREVIATED S)Shall mean a unit of measure of a solid angle the value of which can be determined by placing a sphere so that its center point is upon the vertex of the solid angle and dividing the area measure of the surface area segment of the sphere which subtends the angle by the square of the radius of the sphere (note that this quantity is not dependent upon the shape of the subtending area segment but only upon the measure of the segment area).
TEMPORARY LIGHTINGTemporary lighting is outdoor lighting which does not conform to the provisions of this chapter and which will not be used for longer than a period of 30 consecutive days; temporary lighting is intended for uses which, by their nature, are of limited duration such as holiday decorations, civic events, or construction projects; (note: applications for Temporary Lighting Permits shall be reviewed and permitted on a case-by-case basis).
UNIFORMITYShall mean a term utilized to describe the variation of illuminance upon a given plane where variation is expressed as either the numerical ration of the minimum level of illuminance to the maximum level of illuminance or the numerical ratio of the minimum level of illuminance to the average (i.e., arithmetic mean) level of illuminance.
VERTICAL ILLUMINANCEShall mean the measure, in footcandles, of the total amount of visible light incident upon (i.e. illuminating) a point of a vertical surface taken through the sensor of a light meter held vertically at the point.
VISIBLE LIGHTShall mean electromagnetic radiation which is detectable by a typical human eye.