This Part provides for the regulation of outside lighting to
reduce the intensity to the minimum required for safety and commercial
purposes and to reduce to an absolute minimum the spillover of light
and glare, horizontally and skyward for persons on adjacent properties,
road, operators of motor and other types of vehicles and pedestrians.
Unless specifically defined below, words and phrases used in this Part shall be interpreted to have common English usage, to give effect to the purposes set forth in §
10-501 above, and to provide reasonable application of this Part. As used in this Part, the following terms shall have the meanings indicated, unless a different meaning clearly appears from the context:
FIXTURE
The assembly that houses the lamp or lamps and can include
all or some of the following parts: a housing, a mounting bracket
or pole socket, a lamp holder, a ballast, a reflector or mirror, and/or
a refractor or lens.
FLOODLIGHT or SPOTLIGHT
Any light fixture or lamp that incorporates a reflector or
a refractor to concentrate the light output into a directed beam in
a particular direction.
FOOTCANDLE
A unit of illuminance. One footcandle is one lumen per square
foot.
GLARE
The sensation produced by luminances within the visual field
that is sufficiently greater than the luminance to which the eyes
are adapted to cause annoyance, discomfort, or loss in visual performance
or visibility.
HEIGHT OF LUMINAIRE
The height of a luminaire shall be the vertical distance
from the ground directly below the center line of the luminaire to
the lowest direct-light-emitting part of the luminaire.
ILLUMINANCE
The quantity of light measured in footcandles.
ILLUMINATION
An alternative term for illuminance. Commonly used in a qualitative
or general sense to designate the act of illuminating or the state
of being illuminated.
LAMP
The component of a luminaire that produces light. A generic
term for a man-made source of light, i.e., a light bulb.
LIGHT
Radiant energy that is capable of exciting the retina and
producing a visual sensation. The visible portion of the electromagnetic
spectrum extends from about 380 to 770 nanometers.
LUMEN
A standard unit of luminous flux. Photometrically, it is
the luminous flux emitted within a unit solid angle (one steradian)
by a point source having a uniform luminous intensity of one candela.
One footcandle is one lumen per square foot. For the purposes of this
Part, the lumen-output values shall be the initial lumen output ratings
of a lamp, as specified by the manufacturer of the lamp.
LUMINAIRE
A complete lighting unit consisting of one or more lamps
together with the fixture; other parts designed to control the light
distribution; and other mechanical and electrical components.
LUMINANCE
The physical and measurable quantity corresponding to the
brightness of a surface in a specific area from which light is emitted
or reflected (e.g., a lamp, luminaire, reflecting material).