In order to judge or design the lighting of an interior a person must be able to understand and take into account many aspects of seeing and illumination. Important areas of consideration are--(1) factors that contribute to the visibility of an object: size, brightness, contrast, and time, (2) radiant energy with regard to the visible spectrums of…

This interim report informs the eventual user of the direction of the long-term program; specific criteria are not provided. Five current guidelines in lighting practice were disavowed as follows--(1) that low levels of illumination cause organic harm to the eyes, (2) that the footcandle is the best criterion for determining the proper…

The role of reflected glare and visual viewing angles in near task performance is discussed, and following statements are reported--(1) a worker at a desk normally assumes a position in which his eyes traverse an area of work extending from a point approximately vertically below his eyes to a point not more than 40 degrees from the vertical, (2) a…