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Lighting provided from a source without reflection from other surfaces. In daylighting, this means that the light has traveled on a straight path from the sky (or the sun) to the point of interest. In electrical lighting, it usually describes an installation of ceiling-mounted or suspended luminaires with mostly downward light-distribution characteristics.
Lighting in which luminaires distribute 90% to 100% of the emitted light in the direction of the surface to be illuminated, usually in a downward direction.