Calculation of luminous flux
Average illumination (lx) required from system.
Surface area (m²) of room.
Product of maintenance factors due to dust accumulation on luminaire and lamp aging.
The maintenance category for dust on the luminaire is indicated on the photometric data sheet table 5
and values in diagrams cat. I, II, III, IV, V, VI shown below.
Aging of the fluorescent lamp is measured by the mean depreciation curve shown below.