maintenance factor, <of a lighting installation>
DEPRECATED: light loss factor
DEPRECATED: depreciation factor
Note 1 to entry: The term "light loss factor" is no longer used.
Note 2 to entry: The term "depreciation factor" was formerly used to designate the reciprocal of the above quotient.
Note 3 to entry: The maintenance factor takes into account light losses caused by dirt accumulation on luminaires and room surfaces (in interiors) or other relevant surfaces (in exteriors, where appropriate), and the decrease in the luminous flux of lamps.
Note 4 to entry: The maintenance factor has unit one.
Note 5 to entry: This entry was numbered 17-753 and 17-774 in CIE S 017:2011.