Index: src/Plugins/Wti/Wti.Calculation/Piping/PipingCalculation.cs
===================================================================
diff -u -rff0d3e86209edd5224336bd805466a1c062b00a5 -re4bd298c3f3762925531b11517a0f57b7005e5ad
--- src/Plugins/Wti/Wti.Calculation/Piping/PipingCalculation.cs	(.../PipingCalculation.cs)	(revision ff0d3e86209edd5224336bd805466a1c062b00a5)
+++ src/Plugins/Wti/Wti.Calculation/Piping/PipingCalculation.cs	(.../PipingCalculation.cs)	(revision e4bd298c3f3762925531b11517a0f57b7005e5ad)
@@ -131,8 +131,8 @@
             {
                 ExitPointXCoordinate = input.ExitPointXCoordinate,
                 PhreaticLevel = input.PhreaticLevelExit,
-                SoilProfile = new PipingProfileCreator().Create(),
-                SurfaceLine = new PipingSurfaceLineCreator().Create(),
+                SoilProfile = PipingProfileCreator.Create(),
+                SurfaceLine = PipingSurfaceLineCreator.Create(),
                 VolumicWeightOfWater = input.WaterVolumetricWeight
             };
             calculator.Calculate();
Index: src/Plugins/Wti/Wti.Calculation/Piping/PipingProfileCreator.cs
===================================================================
diff -u -r2f9f3715577a997e8717aedc5f3667627ba7eac5 -re4bd298c3f3762925531b11517a0f57b7005e5ad
--- src/Plugins/Wti/Wti.Calculation/Piping/PipingProfileCreator.cs	(.../PipingProfileCreator.cs)	(revision 2f9f3715577a997e8717aedc5f3667627ba7eac5)
+++ src/Plugins/Wti/Wti.Calculation/Piping/PipingProfileCreator.cs	(.../PipingProfileCreator.cs)	(revision e4bd298c3f3762925531b11517a0f57b7005e5ad)
@@ -11,11 +11,13 @@
         /// Creates a simple <see cref="PipingProfile"/> with a single default constructed <see cref="PipingLayer"/>.
         /// </summary>
         /// <returns></returns>
-        public PipingProfile Create()
+        public static PipingProfile Create()
         {
             var profile = new PipingProfile();
-            var layer = new PipingLayer();
-            layer.IsAquifer = true;
+            var layer = new PipingLayer
+            {
+                IsAquifer = true
+            };
             profile.Layers.Add(layer);
 
             return profile;
Index: src/Plugins/Wti/Wti.Calculation/Piping/PipingSurfaceLineCreator.cs
===================================================================
diff -u -r5fc71a385897af92ccb092f2f969b5709afab85a -re4bd298c3f3762925531b11517a0f57b7005e5ad
--- src/Plugins/Wti/Wti.Calculation/Piping/PipingSurfaceLineCreator.cs	(.../PipingSurfaceLineCreator.cs)	(revision 5fc71a385897af92ccb092f2f969b5709afab85a)
+++ src/Plugins/Wti/Wti.Calculation/Piping/PipingSurfaceLineCreator.cs	(.../PipingSurfaceLineCreator.cs)	(revision e4bd298c3f3762925531b11517a0f57b7005e5ad)
@@ -11,7 +11,7 @@
         /// Creates a simple <see cref="PipingSurfaceLine"/> with a single <see cref="PipingPoint"/> at the origin.
         /// </summary>
         /// <returns></returns>
-        public PipingSurfaceLine Create()
+        public static PipingSurfaceLine Create()
         {
             var surfaceLine = new PipingSurfaceLine();
             surfaceLine.Points.Add(new PipingPoint(0, 0, 0));
Index: test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingCalculationTest.cs
===================================================================
diff -u -r77bd5fae96250f5c6e1eb7acaa848b754d44475d -re4bd298c3f3762925531b11517a0f57b7005e5ad
--- test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingCalculationTest.cs	(.../PipingCalculationTest.cs)	(revision 77bd5fae96250f5c6e1eb7acaa848b754d44475d)
+++ test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingCalculationTest.cs	(.../PipingCalculationTest.cs)	(revision e4bd298c3f3762925531b11517a0f57b7005e5ad)
@@ -33,15 +33,16 @@
                 random.NextDouble(),
                 random.NextDouble(),
                 random.NextDouble());
+
             PipingCalculationResult actual = new PipingCalculation(input).Calculate();
 
-            Assert.That(actual, Is.Not.Null);
-            Assert.That(actual.UpliftZValue, Is.Not.NaN);
-            Assert.That(actual.UpliftFactorOfSafety, Is.Not.NaN);
-            Assert.That(actual.HeaveZValue, Is.Not.NaN);
-            Assert.That(actual.HeaveFactorOfSafety, Is.Not.NaN);
-            Assert.That(actual.SellmeijerZValue, Is.Not.NaN);
-            Assert.That(actual.SellmeijerFactorOfSafety, Is.Not.NaN);
+            Assert.NotNull(actual);
+            Assert.IsFalse(double.IsNaN(actual.UpliftZValue));
+            Assert.IsFalse(double.IsNaN(actual.UpliftFactorOfSafety));
+            Assert.IsFalse(double.IsNaN(actual.HeaveZValue));
+            Assert.IsFalse(double.IsNaN(actual.HeaveFactorOfSafety));
+            Assert.IsFalse(double.IsNaN(actual.SellmeijerZValue));
+            Assert.IsFalse(double.IsNaN(actual.SellmeijerFactorOfSafety));
         }
     }
 }
\ No newline at end of file
Index: test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingProfileCreatorTest.cs
===================================================================
diff -u -r1791d59ecae6050732d7878278154dc4f3bc21f2 -re4bd298c3f3762925531b11517a0f57b7005e5ad
--- test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingProfileCreatorTest.cs	(.../PipingProfileCreatorTest.cs)	(revision 1791d59ecae6050732d7878278154dc4f3bc21f2)
+++ test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingProfileCreatorTest.cs	(.../PipingProfileCreatorTest.cs)	(revision e4bd298c3f3762925531b11517a0f57b7005e5ad)
@@ -7,11 +7,15 @@
     public class PipingProfileCreatorTest
     {
         [Test]
-        public void GivenAPipingProfileCreator_WhenCreatingPipingProfile_ThenAProfileWithALayerIsReturned()
+        public void Create_Always_ReturnsProfileWithSingleAquiferLayer()
         {
-            var pipingProfileCreator = new PipingProfileCreator();
-            PipingProfile actual = pipingProfileCreator.Create();
-            Assert.That(actual.Layers, Is.Not.Empty);
+            // Call
+            PipingProfile actual = PipingProfileCreator.Create();
+
+            // Assert
+            Assert.IsNotNull(actual.Layers);
+            Assert.AreEqual(1, actual.Layers.Count);
+            Assert.IsTrue(actual.Layers[0].IsAquifer);
         }
     }
 }
\ No newline at end of file
Index: test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingSurfaceLineCreatorTest.cs
===================================================================
diff -u -r5fc71a385897af92ccb092f2f969b5709afab85a -re4bd298c3f3762925531b11517a0f57b7005e5ad
--- test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingSurfaceLineCreatorTest.cs	(.../PipingSurfaceLineCreatorTest.cs)	(revision 5fc71a385897af92ccb092f2f969b5709afab85a)
+++ test/Plugins/Wti/Wti.Calculation.Test/Piping/PipingSurfaceLineCreatorTest.cs	(.../PipingSurfaceLineCreatorTest.cs)	(revision e4bd298c3f3762925531b11517a0f57b7005e5ad)
@@ -7,14 +7,16 @@
     public class PipingSurfaceLineCreatorTest
     {
         [Test]
-        public void GivenASurfaceLineCreator_WhenCreatingPipingSurfaceLine_ThenASurfaceLineWithASinglePointAtOrigin()
+        public void Create_Always_ReturnsSurfaceLineWithASinglePointAtOrigin()
         {
-            var pipingSurfaceLineCreator = new PipingSurfaceLineCreator();
-            PipingSurfaceLine actual = pipingSurfaceLineCreator.Create();
-            Assert.That(actual.Points.Count, Is.EqualTo(1));
-            Assert.That(actual.Points[0].X, Is.EqualTo(0));
-            Assert.That(actual.Points[0].Y, Is.EqualTo(0));
-            Assert.That(actual.Points[0].Z, Is.EqualTo(0));
+            // Call
+            PipingSurfaceLine actual = PipingSurfaceLineCreator.Create();
+
+            // Assert
+            Assert.AreEqual(1, actual.Points.Count);
+            Assert.AreEqual(0, actual.Points[0].X);
+            Assert.AreEqual(0, actual.Points[0].Y);
+            Assert.AreEqual(0, actual.Points[0].Z);
         }
     }
 }
\ No newline at end of file