Index: Ringtoets/Piping/src/Ringtoets.Piping.Data/RingtoetsPipingSurfaceLineCollection.cs
===================================================================
diff -u -rc290911dd4647e3115e239c8baf814717c098a5a -r352102f53efcda2247dd7ff8c2d833eccc709c4d
--- Ringtoets/Piping/src/Ringtoets.Piping.Data/RingtoetsPipingSurfaceLineCollection.cs	(.../RingtoetsPipingSurfaceLineCollection.cs)	(revision c290911dd4647e3115e239c8baf814717c098a5a)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Data/RingtoetsPipingSurfaceLineCollection.cs	(.../RingtoetsPipingSurfaceLineCollection.cs)	(revision 352102f53efcda2247dd7ff8c2d833eccc709c4d)
@@ -26,7 +26,8 @@
 namespace Ringtoets.Piping.Data
 {
     /// <summary>
-    /// Collection to store <see cref="RingtoetsPipingSurfaceLine"/>.
+    /// Collection to store <see cref="RingtoetsPipingSurfaceLine"/> items. The 
+    /// names of the items are unique within the collection.
     /// </summary>
     public class RingtoetsPipingSurfaceLineCollection : ObservableUniqueItemCollectionWithSourcePath<RingtoetsPipingSurfaceLine, string>
     {