To evaluate the light pollution caused by light sources the measure ULR (Upward Light Ratio) will be determined.
Normative URL values indicated in standards like EN 12464-2 2014, EN 12193 2018, CIE 150 2017 , ÖNORM O 1052:2022 and NSVV: Lichthinder 2023 have to be fulfilled.  The ULR value, reflects the upper luminous flux emitted by a light source or light sources.

 
By pressing the "Calculate" command under "Obtrusive light" the ULR value will be calculated and shown in the window "Results" > "Obtrusive light" > "General".

Another way to showcase the ULR result in the print output is to open the summary sheet under "Output" > "Result overview" > "Summary obtrusive light", and perform the following actions:

1. In the output itself, right-click on the mouse, then select "Properties".




2- In the properties window, activate under "Overview (Exterior") show ULR value and confirm with the button "OK".

In the summary sheet the calculated ULR value is printed and indicated by a green hook in case the normative value is fulfilled.