§ 285-2. Definitions.

Unless specifically defined below, words or phrases used in this chapter shall be interpreted so as to give them the meaning they have in common usage and to give this chapter its most reasonable application.

AREA LIGHT

Light that produces over 1,800 lumens (See Addendum 1 for light output of various lamps). Area lights include, but are not limited to, streetlights, parking lot lights and yard lights.

AVERAGE FOOTCANDLE

The level of light measured at an average point of illumination between the brightest and darkest areas. The measurement can be made at the ground surface or at four to five feet above the ground.

BALLAST

A device used with a discharge lamp to obtain the necessary voltage, current, and/or wave form for starting and operating the lamp.

BUILDING OFFICIAL

The City of Las Vegas Code Enforcement Department.

BULB

The source of electric light. To be distinguished from the whole assembly (see "luminaire").

CANDELA (cd)

Unit of luminous intensity.

COMMISSION

The City of Las Vegas Planning and Zoning Commission.

EIGHTY-FIVE-DEGREE FULL-CUTOFF-TYPE FIXTURES

Fixtures that do not allow light to escape above an eighty-five-degree angle measured from a vertical line from the center of the lamp extended to the ground.

EXISTING LIGHTING

Any and all lighting installed prior to the effective date of this chapter.

EXTERIOR LIGHTING

Temporary or permanent lighting that is installed, located or used in such a manner to cause light rays to shine outside. Fixtures that are installed indoors that are intended to light something outside are considered exterior lighting for the intent of this chapter.

FIXTURE

The assembly that holds the lamp in a lighting system. It includes the elements designed to give light output control, such as a reflector (mirror) or refractor (lens), the ballast, housing, and the attachment parts.

FLOODLIGHT

Light that produces up to 1,800 lumens (See Addendum 1 for light output of various lamps) and is designed to "flood" a well-defined area with light. Generally, floodlights produce from 1,000 to 1,800 lumens.

FLUX (RADIANT FLUX)

Unit is erg/sec or watts.

FOOTCANDLE

Illumination produced on a surface one foot from a uniform point source of one candela. Measured by a light meter.

FULL-CUTOFF FIXTURES

Fixtures, as installed, that are designed or shielded in such a manner that all light rays emitted by the fixture, either directly from the lamps or indirectly from the fixture, are projected below a horizontal plane running through the lowest point on the fixture where light is emitted.

GLARE

Intense light that results in discomfort and/or a reduction of visual performance and visibility.

HOLIDAY LIGHTING

Festoon-type lights, limited to small individual bulbs on a string, where the spacing of bulbs is not closer than three inches and where the output per bulb is no greater than 15 lumens.

IESNA

Illuminating Engineering Society of North America (IES or IESNA), the professional society of lighting engineers, including those from manufacturing companies, and others professionally involved in lighting.

ILLUMINANCE

Density of luminous flux incident on a surface. Unit is footcandle or lux.

LAMP

The source of electric light: the bulb and its housing. To be distinguished from the whole assembly (see "luminaire").

LIGHT

The form of radiant energy acting on the retina of the eye to make sight possible; brightness; illumination; a lamp, as defined above.

LIGHTING

Any or all parts of a luminaire that function to produce light.

LIGHT POLLUTION

Any adverse effect of man-made light including, but not limited to, light trespass, uplighting, the uncomfortable distraction to the eye, or any man-made light that diminishes the ability to view the night sky. Often used to denote urban sky glow.

LIGHT TRESPASS

Light falling where it is not wanted or needed, generally caused by a light on a property that shines onto the property of others.

LUMEN

Unit of luminous flux; the flux emitted within a unit solid angle by a point source with a uniform luminous intensity of one candela. One footcandle is one lumen per square foot. One lux is one lumen per square meter.

LUMINAIRE

The complete lighting unit, including the lamp, the fixture, and other parts.

LUMINANCE

At a point and in a given direction, the luminous intensity in the given direction produced by an element of the surface surrounding the point divided by the area of the projection of the element on a plane perpendicular to the given direction. Units: candelas per unit area. The luminance is the perceived brightness that we see, the visual effect of the illuminance, reflected, emitted or transmitted from a surface.

NONESSENTIAL

Lighting that is not necessary for an intended purpose after the purpose has been served. Does not include any lighting used for safety and/or public circulation purposes. Example: For purposes of this chapter, lighting for a business sign is considered essential during business hours, however, is considered nonessential once the business is closed.

PARTIALLY SHIELDED

The bulb of the fixture is shielded by a translucent siding and the bulb is not visible at all. Light may be emitted at the horizontal level of the bulb.

PLANNING AND ZONING COMMISSION

The City of Las Vegas Planning and Zoning Commission or a member of the City of Las Vegas Community Development/Code Enforcement staff.

RECESSED

When a light is built into a structure or portion of a structure such that the light is fully cut off and no part of the light extends or protrudes beyond the underside of a structure or portion of a structure.

SHIELDED

When the light emitted from the fixture is projected below a horizontal plane running through the lowest point of the fixture where light is emitted. The bulb is not visible with a shielded light fixture, and no light is emitted from the sides of the fixture. Also considered a full-cutoff fixture.

TEMPORARY LIGHTING

Lighting that is intended to be used for a special event for seven days or less.

UPLIGHTING

Lighting that is directed in such a manner as to shine light rays above the horizontal plane.