Index: Ringtoets/Revetment/test/Ringtoets.Revetment.Service.Test/WaveConditionsCalculationServiceBaseTest.cs
===================================================================
diff -u -rb9ae753b52b2b198f264bd2f825d4a66305ad5c9 -r74d0528380e5607f4d2646b8b7daf40acad6e3f6
--- Ringtoets/Revetment/test/Ringtoets.Revetment.Service.Test/WaveConditionsCalculationServiceBaseTest.cs	(.../WaveConditionsCalculationServiceBaseTest.cs)	(revision b9ae753b52b2b198f264bd2f825d4a66305ad5c9)
+++ Ringtoets/Revetment/test/Ringtoets.Revetment.Service.Test/WaveConditionsCalculationServiceBaseTest.cs	(.../WaveConditionsCalculationServiceBaseTest.cs)	(revision 74d0528380e5607f4d2646b8b7daf40acad6e3f6)
@@ -564,7 +564,7 @@
                 for (var i = 0; i < nrOfCalculators; i++)
                 {
                     WaveConditionsCosineCalculationInput expectedInput = CreateInput(waterLevels[i], a, b, c, norm, input, useForeshore, false);
-                    HydraRingDataEqualityHelper.AreEqual(expectedInput, calculator.ReceivedInputs[i]);
+                    HydraRingDataEqualityHelper.AreEqual(expectedInput, calculator.ReceivedInputs.ElementAt(i));
                 }
             }
 
@@ -630,7 +630,7 @@
                 for (var i = 0; i < nrOfCalculators; i++)
                 {
                     WaveConditionsCosineCalculationInput expectedInput = CreateInput(waterLevels[i], a, b, c, norm, input, true, true);
-                    HydraRingDataEqualityHelper.AreEqual(expectedInput, calculator.ReceivedInputs[i]);
+                    HydraRingDataEqualityHelper.AreEqual(expectedInput, calculator.ReceivedInputs.ElementAt(i));
                 }
             }
 
@@ -690,7 +690,7 @@
                 // Assert
                 for (var i = 0; i < nrOfCalculators; i++)
                 {
-                    Assert.AreEqual(usePreprocessor, calculator.ReceivedInputs[i].PreprocessorSetting.RunPreprocessor);
+                    Assert.AreEqual(usePreprocessor, calculator.ReceivedInputs.ElementAt(i).PreprocessorSetting.RunPreprocessor);
                 }
             }