Definition of Terms
1.---------Ratio of the flux absorbed by a medium to the incident6 flux.
2.---------General term for the process by which incident flux is dissipated.
3.---------Directional lighting to emphasize a particular object or draw attention to a part of the field or view.
4.---------Angular distance of the sun measured up from the horizon of the great circle that passes perpendicular to the plane of the horizon through the sun and through the zenith.
5.---------Angular distance between the vertical plane containing the sun and the plane of the meridian.
6.---------A single opaque or translucent element to shield a source from direct view at certain angles or to absorb unwanted light.
7.---------Device used with electric discharge lamp to obtain the necessary circuit conditions for starting the operating.
8.---------Popular term for ultraviolet energy near the visible spectrum.
9.---------The terms Brightness and Luminance are almost entirely interchangeable, with the latter being the newer term. (See Luminance).
10.--------The unit of Luminous intensity.
11.--------Luminous intensity expressed in candelas.
12.--------General lighting system in which the entire ceiling is, in effect, one large luminaire, as in louvered ceiling and luminous ceilings.
13.--------Cavity formed by the ceiling, the plane of the luminaries, and the wall surfaces between this two planes.
14.--------Enclosure containing the ballast, starter, lamp holders, and wiring for a fluorescent lamp.
15.---------Sky having less than 30% cloud cover.
16.---------Part of a building rising clear of the roofs and whose walls contains windows for lighting the interior.
17.---------Ratio of the luminous flux (lumens) from a luminaire received on the work