Index: Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingCalculationTest.cs
===================================================================
diff -u -r17b11c850b35c3ea99150ba25098b5b769b58f4f -r07f3d67fe9512b3c8303ff09398b0a234900d546
--- Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingCalculationTest.cs	(.../PipingCalculationTest.cs)	(revision 17b11c850b35c3ea99150ba25098b5b769b58f4f)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingCalculationTest.cs	(.../PipingCalculationTest.cs)	(revision 07f3d67fe9512b3c8303ff09398b0a234900d546)
@@ -52,6 +52,7 @@
 
             // Assert
             Assert.IsInstanceOf<ICalculation>(calculation);
+            Assert.IsInstanceOf<CloneableObservable>(calculation);
 
             Assert.AreEqual("Nieuwe berekening", calculation.Name);