13
The Lighting Handbook
Maintenance value maintenance factor initial value
Relative illuminance (%)
Operating time
(years)
– Initial value
– Maintained
illuminance with
3-year cleaning
–
System value with-
out maintenance
150
1 5
125
100
75
50
25
0
Reflectance factors
The reflectance factors the room and
object surfaces determine not only the
perception the room but also the reflected
light and thus the room’s brightness.
The reflectance factor table the system
helps you determine the reflectance factors.
