Secrets of Lighting: Library Book Stack Illumination and Its Influences on Readers' Book-Searching Behaviors

Book stack illuminance was recorded by a lumin degrees meter from September 2016 through September 2017 based on tracking-observation in two libraries at the University of Illinois at Urbana and Champaign in the US and the Jiangsu University Library in China. Independent-samples T test and one-way analysis of variance were used for records data analysis. Further, an experiment was designed to measure the effects of book stack lighting environment on readers' book-searching behaviors. Independent-samples T test was used for experiment data analysis. It was found that the seasonal illuminance of book stacks changed irregularly, which meant that two hypotheses (1 and 2) central to this study were not fully supported, and the day-night illumination differences on the stacks was significant in UIUC libraries for three seasons, and completely significant in JSU Library. In the course of behavior experiments, stack lighting had no significant effect on American participants' searching performance, while the results in the library of China were diametrically opposite. Therefore, the lighting system in book stacks should be optimized through choosing the appropriate light sources, adjusting the approaches to book stack lighting and, even more, considering readers' expectation and perception during library lighting designing, so as to increase their efficiency in book-searching.