Index: Ringtoets/GrassCoverErosionOutwards/test/Ringtoets.GrassCoverErosionOutwards.Service.Test/GrassCoverErosionOutwardsCalculationActivityFactoryTest.cs
===================================================================
diff -u -r4dda50f1a04886107a4d153a2420b61d15029be4 -r74d0528380e5607f4d2646b8b7daf40acad6e3f6
--- Ringtoets/GrassCoverErosionOutwards/test/Ringtoets.GrassCoverErosionOutwards.Service.Test/GrassCoverErosionOutwardsCalculationActivityFactoryTest.cs	(.../GrassCoverErosionOutwardsCalculationActivityFactoryTest.cs)	(revision 4dda50f1a04886107a4d153a2420b61d15029be4)
+++ Ringtoets/GrassCoverErosionOutwards/test/Ringtoets.GrassCoverErosionOutwards.Service.Test/GrassCoverErosionOutwardsCalculationActivityFactoryTest.cs	(.../GrassCoverErosionOutwardsCalculationActivityFactoryTest.cs)	(revision 74d0528380e5607f4d2646b8b7daf40acad6e3f6)
@@ -329,7 +329,7 @@
             {
                 activity.Run();
 
-                Assert.AreEqual(nrOfCalculations, testCalculator.ReceivedInputs.Count);
+                Assert.AreEqual(nrOfCalculations, testCalculator.ReceivedInputs.Count());
                 foreach (WaveConditionsCosineCalculationInput input in testCalculator.ReceivedInputs)
                 {
                     Assert.AreEqual(calculation.InputParameters.BreakWater.Height, input.BreakWater.Height);
Index: Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.TestUtil/Calculator/TestHydraRingCalculatorFactory.cs
===================================================================
diff -u -r75c87ba087fcb4bf89090d844455b215b25b4a75 -r74d0528380e5607f4d2646b8b7daf40acad6e3f6
--- Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.TestUtil/Calculator/TestHydraRingCalculatorFactory.cs	(.../TestHydraRingCalculatorFactory.cs)	(revision 75c87ba087fcb4bf89090d844455b215b25b4a75)
+++ Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.TestUtil/Calculator/TestHydraRingCalculatorFactory.cs	(.../TestHydraRingCalculatorFactory.cs)	(revision 74d0528380e5607f4d2646b8b7daf40acad6e3f6)
@@ -105,12 +105,21 @@
 
     public class TestHydraRingCalculator<T>
     {
-        public readonly List<T> ReceivedInputs = new List<T>();
         public readonly HydraRingCalculationException HydraRingCalculationException = new HydraRingCalculationException();
+        private readonly List<T> receivedInputs = new List<T>();
         public event EventHandler CalculationFinishedHandler;
+
         public bool EndInFailure { get; set; }
         public bool IsCanceled { get; private set; }
 
+        public IEnumerable<T> ReceivedInputs
+        {
+            get
+            {
+                return receivedInputs;
+            }
+        }
+
         public GeneralResult IllustrationPointsResult { get; set; }
 
         public void Calculate(T input)
@@ -119,8 +128,9 @@
             {
                 throw HydraRingCalculationException;
             }
-            ReceivedInputs.Add(input);
 
+            receivedInputs.Add(input);
+
             CalculationFinished(EventArgs.Empty);
         }
 
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);
                 }
             }
 
Index: Ringtoets/StabilityStoneCover/test/Ringtoets.StabilityStoneCover.Service.Test/StabilityStoneCoverWaveConditionsCalculationActivityFactoryTest.cs
===================================================================
diff -u -rf8f4f06311e58fd749631bdb933d8f8468ce56f8 -r74d0528380e5607f4d2646b8b7daf40acad6e3f6
--- Ringtoets/StabilityStoneCover/test/Ringtoets.StabilityStoneCover.Service.Test/StabilityStoneCoverWaveConditionsCalculationActivityFactoryTest.cs	(.../StabilityStoneCoverWaveConditionsCalculationActivityFactoryTest.cs)	(revision f8f4f06311e58fd749631bdb933d8f8468ce56f8)
+++ Ringtoets/StabilityStoneCover/test/Ringtoets.StabilityStoneCover.Service.Test/StabilityStoneCoverWaveConditionsCalculationActivityFactoryTest.cs	(.../StabilityStoneCoverWaveConditionsCalculationActivityFactoryTest.cs)	(revision 74d0528380e5607f4d2646b8b7daf40acad6e3f6)
@@ -339,7 +339,7 @@
             {
                 activity.Run();
 
-                Assert.AreEqual(nrOfCalculations, testCalculator.ReceivedInputs.Count);
+                Assert.AreEqual(nrOfCalculations, testCalculator.ReceivedInputs.Count());
                 foreach (WaveConditionsCosineCalculationInput input in testCalculator.ReceivedInputs)
                 {
                     Assert.AreEqual(calculation.InputParameters.BreakWater.Height, input.BreakWater.Height);
Index: Ringtoets/WaveImpactAsphaltCover/test/Ringtoets.WaveImpactAsphaltCover.Service.Test/WaveImpactAsphaltCoverWaveConditionsCalculationActivityFactoryTest.cs
===================================================================
diff -u -r27e5197a81bb42ec0c00d4345ebca38815506a02 -r74d0528380e5607f4d2646b8b7daf40acad6e3f6
--- Ringtoets/WaveImpactAsphaltCover/test/Ringtoets.WaveImpactAsphaltCover.Service.Test/WaveImpactAsphaltCoverWaveConditionsCalculationActivityFactoryTest.cs	(.../WaveImpactAsphaltCoverWaveConditionsCalculationActivityFactoryTest.cs)	(revision 27e5197a81bb42ec0c00d4345ebca38815506a02)
+++ Ringtoets/WaveImpactAsphaltCover/test/Ringtoets.WaveImpactAsphaltCover.Service.Test/WaveImpactAsphaltCoverWaveConditionsCalculationActivityFactoryTest.cs	(.../WaveImpactAsphaltCoverWaveConditionsCalculationActivityFactoryTest.cs)	(revision 74d0528380e5607f4d2646b8b7daf40acad6e3f6)
@@ -340,7 +340,7 @@
             {
                 activity.Run();
 
-                Assert.AreEqual(nrOfCalculations, testCalculator.ReceivedInputs.Count);
+                Assert.AreEqual(nrOfCalculations, testCalculator.ReceivedInputs.Count());
                 foreach (WaveConditionsCosineCalculationInput input in testCalculator.ReceivedInputs)
                 {
                     Assert.AreEqual(calculation.InputParameters.BreakWater.Height, input.BreakWater.Height);