Definitions. As used in this section, the following terms shall have the meanings indicated:
ESSENTIAL LIGHTING
Light that is used for a specified period of time, which is necessary for location identification, safety, security or public circulation purposes.
FOOTCANDLE (FC)
The basic unit of illuminance (the amount of light falling on a surface). Footcandle measurement is taken with a light meter. One footcandle is approximately equal to the illuminance produced by a light source of one candela in intensity, measured on a surface at a one-foot distance from the source. Horizontal footcandles measure the illumination striking a horizontal plane. Footcandle values can be measured directly with certain handheld incident light meters.
FULL CUTOFF (FCO)
A classification for a luminaire designed and installed where no light is emitted at or above a horizontal plane running through the lowest point on the luminaire. In addition, the luminous intensity (as measured in candelas) emitted at any angle from 80° up to 90° cannot exceed a numerical value equal to 10% of the lumen rating of the lamp, as reported in a photometric report from the manufacturer. A cutoff or semi-cutoff design allows a restricted amount of light emitted above the horizontal, and a noncutoff provides no restriction against light emitted above the horizontal.
FULLY SHIELDED
A luminaire constructed and installed in such a manner that all light emitted by it, either directly from the lamp or a diffusing element, or indirectly by reflection or refraction from any part of the luminaire, is projected below the horizontal. It is the same as a full cutoff luminaire but without any restrictions on light distribution below the horizontal plane, and it can be identified without a manufacturer's report.
GLARE
Unshielded direct light from a light source that results in light shining in the eyes in such a manner to impair the ability to see other objects.
ILLUMINANCE
The intensity or amount of light falling at a given place on a lighted surface, expressed in lumens per square meter and footcandles per square foot.
LED LIGHTING
Light-emitting diode lighting products.
LIGHT POLLUTION
Stray or reflected light that is emitted into the atmosphere above the 90° horizontal plane from the luminaire, or which can or does cause sky glow.
LIGHT TRESPASS
Direct light from an artificial light source on one property that is intruding into an area where it is not wanted or does not belong.
LIGHT, DIRECT
Light emitted directly from the lamp, off of the reflector or reflector diffuser, or through the refractor or diffuser lens, of a luminaire.
LIGHT, INDIRECT
Direct light that has been reflected or has scattered off of surfaces other than those associated with the light fixture.
LIGHTING, OUTDOOR
The nighttime illumination of an outside area or object by any manufactured device located outdoors that produces light by any means.
LUMEN
A metric unit used to measure the amount of light that is produced by a light source. The lumen quantifies the amount of light energy produced by a lamp at the lamp, not by the energy input, which is indicated by the wattage.
LUMINAIRE
A complete lighting system, including a light source component (lamp or lamps that produce the actual light) and a fixture.
NONESSENTIAL EXTERIOR LIGHTING
Lighting which is unnecessary for pedestrian passage and not generally useful (e.g., decorative and 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).
SKY GLOW
Brightness of the night sky as a result of artificial light which is emitted upward by luminaires.