Definitions. Except as noted hereinafter, all definitions are provided in the Zoning Bylaw. Unless the context clearly indicates otherwise, certain words and phrases used in this section shall have the meaning indicated below. Although set forth here for convenience, the terms shall have the same effect as if set forth in Article
II, Definitions.
COLOR RENDERING INDEX (CRI)
A measurement of the amount of color shift that objects undergo
when lighted by a light source as compared with the color of those
same objects when seen under a reference light source of comparable
color temperature. CRI values generally range from zero to 100, where
100 represents incandescent light.
COLOR TEMPERATURE
Color temperature or chromaticity refers to the color appearance
of the light that comes from a light source, also referred to as correlated
color temperature (CCT). The apparent color of a light source is measured
in degrees Kelvin or "K." A low color temperature corresponds to "warm."
Incandescent lamps are in the range of 2,700 degrees K. "Cool" light
comes from sources such as cool white fluorescent lamps operating
at 4,100 degrees K. Lights appear bluer above 4,100 degrees K.
CUTOFF ANGLE
The angle formed by a line drawn from the direction of the
direct light rays at the light source with respect to the vertical,
beyond which no direct light is emitted.
DIRECT LIGHT
Light emitted directly by a lamp, off a reflector, or through
a refractor of an outdoor light fixture or luminaire.
EFFICACY
Efficacy is the rate at which a lamp is able to convert electrical
power (watts) into light (lumens), expressed in terms of lumens per
watt.
FILTERED
When referring to an outdoor light fixture means that the
fixture is to be fitted with a glass, acrylic, or other translucent
enclosure of the light source.
FIXTURE
The assembly that houses a lamp or lamps, and which may include
a housing, a mounting bracket or pole socket, a lamp holder, a ballast,
a reflector or mirror, and/or a refractor, lens, or diffuser lens.
FULLY SHIELDED LUMINAIRE
A lamp and fixture assembly designed with a cutoff angle
of 90 degrees, so that no direct light is emitted above a horizontal
plane.
GLARE
Light emitted from a luminaire with intensity great enough
to produce unreasonable annoyance, discomfort, or a reduction in a
viewer's ability to see.
HEIGHT OF LUMINAIRE
The vertical distance from the finished grade of the ground
directly below to the lowest direct light emitting part of the luminaire.
INDIRECT LIGHT
Direct light that has been reflected off other surfaces.
LAMP
The component of an outdoor light fixture that produces light.
LIGHT TRESPASS
The shining of direct and/or reflected light produced by
a luminaire beyond the boundaries of the property on which the outdoor
or indoor light fixture is located.
LUMEN
A measure of light energy generated by a light source. One
footcandle is one lumen per square foot. For purposes of the bylaw,
the lumen output shall be the initial lumen output of a lamp, as rated
by the manufacturer.
LUMNAIRE
Complete lighting unit, consisting of one or more lamps (bulbs
or tubes that emit light), along with the socket and other parts that
hold the lamp in place and protect it, wiring that connects the lamp
to a power source, and a reflector that helps direct and distribute
the light.
SHIELDED
When referring to an outdoor light fixture means that the
fixture allows no up light and/or light trespass.
UP LIGHT
Direct light emitted by an outdoor light fixture above a
horizontal plane through the fixture's lowest light emitting part.