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surround ratio

SR, <in road lighting>


average illuminance on strips, which are adjacent to the edges of both sides of the carriageway, to the average illuminance on the adjacent strips in the carriageway

Note 1 to entry: Specific requirements regarding the width of the strips are defined in CIE 140 Road Lighting Calculations.

Note 2 to entry: The surround ratio has unit one.

Note 3 to entry: This entry was numbered 17-1286 and 17-1253 in CIE S 017:2011.

Publication date: 2020-12
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