LAUSR

Abstract Sports facilities all over the world apply LED lighting. The combination of high luminance and small luminous surfaces causes a high probability of glare and LED lighting contains these specifications. There are specific situations for which validated glare models exist, such as offices or outdoor soccer fields, although indoor sports facilities are not one of them. Additionally, we do not know the degree to which lighting may impact athletes' performance. Contradictory research exists on whether glare decreases task performance, and whether any decrease is due to discomfort glare or disability glare. In the current research, objective performance measurements were conducted on a volleyball court with both amateur and professional athletes from the Dutch national indoor volleyball competition—the Eredivisie. An eye tracker was used to see if gaze data contributed to a better understanding of performance or the subjective experience of glare. The results show that athletes' performance was not decreased due to glare, although the subjective experiences, measured by discomfort and non-acceptance, increased significantly. The current unified glare rating (UGR) glare model has a strong correlation with the discomfort findings, although the combination of source luminance and background luminance predicts discomfort and non-acceptance even better. This paper demonstrates that existing glare models perform well for indoor sports environments.