The Office Lighting Recommended Practice (RP-1) is published by the Illuminating Engineering Society of North America. This publication provides guidelines for luminaire performance and design issues related to lighting an office/VDT environment. The table below is taken from this publication. The complete RP-1 can be ordered from the IESNA web site.
Table 7-1. Recommended preferred and maximum average luminances for luminaires used in the direct lighting of a VDT environment. Luminance is measured along the lengthwise, crosswise and 45 degree horizontal planes.
Degrees from vertical
Preferred maximum average luminance
Maximum average luminance
55 degrees
850 cd/m2
--
65 degrees
350 cd/m2
850 cd/m2
75 degrees
175 cd/m2
350 cd/m2
85 degrees or more
175 cd/m2
175 cd/m2