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Glare (UGR)

Glare occurs when parts of the visual field are much brighter than their surroundings, causing discomfort or reduced visibility. The Unified Glare Rating (UGR) is an international measure used to quantify discomfort glare from indoor luminaires. It considers factors such as the luminance of the luminaire, its position in the field of view, and background brightness. The UGR scale typically ranges from 10 (very low glare) to 30 or higher (high glare). Most office environments aim for UGR < 19 to maintain visual comfort and productivity. Proper luminaire design, shielding, and layout can all help reduce glare and create a balanced lighting environment.

Think: Too bright = uncomfortable eyes