UGR reference values 4H, 8H

If the room measurements and reflectance value are unknown at the time of planning, UGR reference values for the reference room with the dimensions 4 H and 8 H, 0,7 for the ceiling reflectance value, 0,5 for the walls and 0,2 for the floor, and across as well as longitudinally to the luminaires for the viewing direction can be used to assess glare. These UGR reference values are also used for luminaire labelling. The luminaire arrangements and observer positions are highlighted blue in fig., the reference values are highlighted grey in table.

Example: At a room height of h = 3,0 m and ceiling-mounted luminaires (suspension length p = 0,0 m), is H = h – p – 1,2 m = 1,8 m and the reference room has the real measurements 4H = 7,2 m and 8H = 14,4 m.