Index: Ringtoets/Piping/test/Ringtoets.Piping.Service.Test/PipingCalculationServiceTest.cs
===================================================================
diff -u -r4ed2f23175341a2f0a836874dce514cd88e96e8d -r487d53ee7ab88f79d75c4932266eaafe08df1a56
--- Ringtoets/Piping/test/Ringtoets.Piping.Service.Test/PipingCalculationServiceTest.cs	(.../PipingCalculationServiceTest.cs)	(revision 4ed2f23175341a2f0a836874dce514cd88e96e8d)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Service.Test/PipingCalculationServiceTest.cs	(.../PipingCalculationServiceTest.cs)	(revision 487d53ee7ab88f79d75c4932266eaafe08df1a56)
@@ -1046,19 +1046,17 @@
             UpliftCalculatorStub upliftCalculator = testFactory.LastCreatedUpliftCalculator;
             SellmeijerCalculatorStub sellmeijerCalculator = testFactory.LastCreatedSellmeijerCalculator;
 
-            var derivedPipingInput = new DerivedPipingInput(input);
-
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetThicknessCoverageLayer(input).GetDesignValue(),
                             heaveCalculator.DTotal,
-                            derivedPipingInput.ThicknessCoverageLayer.GetAccuracy());
+                            DerivedPipingInput.GetThicknessCoverageLayer(input).GetAccuracy());
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetPhreaticLevelExit(input).GetDesignValue(),
                             heaveCalculator.HExit,
                             input.PhreaticLevelExit.GetAccuracy());
             Assert.AreEqual(input.CriticalHeaveGradient, heaveCalculator.Ich);
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetPhreaticLevelExit(input).GetDesignValue(),
                             heaveCalculator.PhiPolder,
                             input.PhreaticLevelExit.GetAccuracy());
-            Assert.AreEqual(derivedPipingInput.PiezometricHeadExit.Value, heaveCalculator.PhiExit);
+            Assert.AreEqual(DerivedPipingInput.GetPiezometricHeadExit(input).Value, heaveCalculator.PhiExit);
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetDampingFactorExit(input).GetDesignValue(),
                             heaveCalculator.RExit,
                             input.DampingFactorExit.GetAccuracy());
@@ -1068,7 +1066,7 @@
                             input.PhreaticLevelExit.GetAccuracy());
             Assert.AreEqual(input.AssessmentLevel.Value, upliftCalculator.HRiver);
             Assert.AreEqual(input.UpliftModelFactor, upliftCalculator.ModelFactorUplift);
-            Assert.AreEqual(derivedPipingInput.PiezometricHeadExit.Value, upliftCalculator.PhiExit);
+            Assert.AreEqual(DerivedPipingInput.GetPiezometricHeadExit(input).Value, upliftCalculator.PhiExit);
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetPhreaticLevelExit(input).GetDesignValue(),
                             upliftCalculator.PhiPolder,
                             input.PhreaticLevelExit.GetAccuracy());
@@ -1085,7 +1083,7 @@
 
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetSeepageLength(input).GetDesignValue(),
                             sellmeijerCalculator.SeepageLength,
-                            derivedPipingInput.SeepageLength.GetAccuracy());
+                            DerivedPipingInput.GetSeepageLength(input).GetAccuracy());
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetPhreaticLevelExit(input).GetDesignValue(),
                             sellmeijerCalculator.HExit,
                             input.PhreaticLevelExit.GetAccuracy());
@@ -1098,17 +1096,17 @@
             Assert.AreEqual(input.BeddingAngle, sellmeijerCalculator.BeddingAngle);
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetThicknessCoverageLayer(input).GetDesignValue(),
                             sellmeijerCalculator.DTotal,
-                            derivedPipingInput.ThicknessCoverageLayer.GetAccuracy());
+                            DerivedPipingInput.GetThicknessCoverageLayer(input).GetAccuracy());
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetDiameter70(input).GetDesignValue(),
                             sellmeijerCalculator.D70,
-                            derivedPipingInput.DiameterD70.GetAccuracy());
+                            DerivedPipingInput.GetDiameterD70(input).GetAccuracy());
             Assert.AreEqual(input.MeanDiameter70, sellmeijerCalculator.D70Mean);
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetThicknessAquiferLayer(input).GetDesignValue(),
                             sellmeijerCalculator.DAquifer,
-                            derivedPipingInput.ThicknessAquiferLayer.GetAccuracy());
+                            DerivedPipingInput.GetThicknessAquiferLayer(input).GetAccuracy());
             Assert.AreEqual(PipingSemiProbabilisticDesignVariableFactory.GetDarcyPermeability(input).GetDesignValue(),
                             sellmeijerCalculator.DarcyPermeability,
-                            derivedPipingInput.DarcyPermeability.GetAccuracy());
+                            DerivedPipingInput.GetDarcyPermeability(input).GetAccuracy());
             Assert.AreEqual(input.SandParticlesVolumicWeight, sellmeijerCalculator.GammaSubParticles);
             Assert.AreEqual(input.Gravity, sellmeijerCalculator.Gravity);
         }