According to the WELL v2™ feature L02: Visual Lighting Design, the project must provide visual comfort and enhance visual acuity for all users through electric lighting1.One of the design considerations for achieving this is to ensure illuminance uniformity on horizontal task planes, such as desks, tables, or counters,where visual tasks are performed2.Illuminance uniformity is the ratio of the minimum to the average illuminance on a given plane, and it indicates how evenly the light is distributed across the surface3.A high illuminance uniformity can prevent glare, contrast, or shadows that may impair visual comfort and performance4.Option A is incorrect, as CRI 90 in circulation areas is not a requirement for visual comfort, but rather for electric light quality, which is addressed by feature L081.Option C is incorrect, as luminance ratios on vertical adjacent zones are not a requirement for visual comfort, but rather for visualbalance, which is addressed by feature L071.Option D is incorrect, as automatic changes in lighting characteristics over a period of five minutes are not a requirement for visual comfort, but rather for circadian lighting design, which is addressed by feature L031.
References: =Standard | WELL V2- Feature L02: Visual Lighting DesignStandard | WELL V2- Feature L02:
Visual Lighting Design - Part 1: ProvideVisual Acuity For All SpacesIlluminance Uniformity- Lighting Research CenterLighting Design Basics- Mark Karlen, James R. Benya, and Christina Spangler