Index: Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismAssemblyFactoryTest.cs
===================================================================
diff -u -rd619ae4aa81f29db83eddda6620ce58b47d864af -rc1ad8e8431d65da2f22adeb93f9deddd9fae77e3
--- Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismAssemblyFactoryTest.cs	(.../PipingFailureMechanismAssemblyFactoryTest.cs)	(revision d619ae4aa81f29db83eddda6620ce58b47d864af)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismAssemblyFactoryTest.cs	(.../PipingFailureMechanismAssemblyFactoryTest.cs)	(revision c1ad8e8431d65da2f22adeb93f9deddd9fae77e3)
@@ -893,7 +893,7 @@
                     Enumerable.Empty<PipingCalculationScenario>(),
                     failureMechanism,
                     assessmentSection);
-                Assert.AreEqual(categoryGroup, expectedAssembly.Group);
+                Assert.AreEqual(expectedAssembly.Group, categoryGroup);
                 mocks.VerifyAll();
             }
         }
@@ -929,7 +929,7 @@
                 FailureMechanismSectionAssembly expectedAssembly = calculator.AssembleManual(
                     sectionResult.ManualAssemblyProbability,
                     AssemblyCategoriesInputFactory.CreateAssemblyCategoriesInput(0.0, failureMechanism, assessmentSection));
-                Assert.AreEqual(categoryGroup, expectedAssembly.Group);
+                Assert.AreEqual(expectedAssembly.Group, categoryGroup);
                 mocks.VerifyAll();
             }
         }
@@ -1042,7 +1042,10 @@
         {
             // Setup
             var failureMechanism = new PipingFailureMechanism();
-            failureMechanism.AddSection(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+            FailureMechanismTestHelper.SetSections(failureMechanism, new[]
+            {
+                FailureMechanismSectionTestFactory.CreateFailureMechanismSection()
+            });
 
             var mocks = new MockRepository();
             IAssessmentSection assessmentSection = AssessmentSectionHelper.CreateAssessmentSectionStub(failureMechanism, mocks);
@@ -1074,7 +1077,10 @@
         {
             // Setup
             var failureMechanism = new PipingFailureMechanism();
-            failureMechanism.AddSection(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+            FailureMechanismTestHelper.SetSections(failureMechanism, new[]
+            {
+                FailureMechanismSectionTestFactory.CreateFailureMechanismSection()
+            });
             PipingFailureMechanismSectionResult sectionResult = failureMechanism.SectionResults.Single();
             sectionResult.UseManualAssemblyProbability = true;
             sectionResult.ManualAssemblyProbability = new Random(39).NextDouble();
@@ -1165,7 +1171,10 @@
         {
             // Setup
             var failureMechanism = new PipingFailureMechanism();
-            failureMechanism.AddSection(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+            FailureMechanismTestHelper.SetSections(failureMechanism, new[]
+            {
+                FailureMechanismSectionTestFactory.CreateFailureMechanismSection()
+            });
 
             var mocks = new MockRepository();
             IAssessmentSection assessmentSection = AssessmentSectionHelper.CreateAssessmentSectionStub(failureMechanism, mocks);