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upward light output ratio
ULOR
quotient of the upward luminous flux of a luminaire, measured under specified conditions with its own lamp(s) and equipment, and the sum of the individual luminous fluxes of the same lamp(s) when operated outside the luminaire with the same equipment, under specified practical conditions
Note 1 to entry: The upward light output ratio has unit one.
Note 2 to entry: This entry was numbered 17-1380 and 17-1359 in CIE S 017:2011.