Index: Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/FailureMechanismSectionConfigurationProperties.cs
===================================================================
diff -u -red517ce7cfed48e23a3dd4c1381bdfb778cd9f70 -re0618171a8bece9ed88594171c5c824b7f4d44dd
--- Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/FailureMechanismSectionConfigurationProperties.cs	(.../FailureMechanismSectionConfigurationProperties.cs)	(revision ed517ce7cfed48e23a3dd4c1381bdfb778cd9f70)
+++ Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/FailureMechanismSectionConfigurationProperties.cs	(.../FailureMechanismSectionConfigurationProperties.cs)	(revision e0618171a8bece9ed88594171c5c824b7f4d44dd)
@@ -53,13 +53,7 @@
         public FailureMechanismSectionConfigurationProperties(FailureMechanismSectionConfiguration sectionConfiguration, double sectionStart, double sectionEnd, double b)
             : base(sectionConfiguration?.Section ?? throw new ArgumentNullException(nameof(sectionConfiguration)), sectionStart, sectionEnd)
         {
-            if (sectionConfiguration == null)
-            {
-                throw new ArgumentNullException(nameof(sectionConfiguration));
-            }
-
             this.sectionConfiguration = sectionConfiguration;
-
             LengthEffectNRounded = new RoundedDouble(2, this.sectionConfiguration.GetN(b));
         }
 
Index: Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/FailureMechanismSectionConfigurationsProperties.cs
===================================================================
diff -u -r96b61af9ad742c4d07dc6e58553e826a6f7afe81 -re0618171a8bece9ed88594171c5c824b7f4d44dd
--- Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/FailureMechanismSectionConfigurationsProperties.cs	(.../FailureMechanismSectionConfigurationsProperties.cs)	(revision 96b61af9ad742c4d07dc6e58553e826a6f7afe81)
+++ Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/FailureMechanismSectionConfigurationsProperties.cs	(.../FailureMechanismSectionConfigurationsProperties.cs)	(revision e0618171a8bece9ed88594171c5c824b7f4d44dd)
@@ -112,10 +112,19 @@
 
         public void Dispose()
         {
-            failureMechanismObserver.Dispose();
-            sectionConfigurationsObserver.Dispose();
+            Dispose(true);
+            GC.SuppressFinalize(this);
         }
 
+        protected virtual void Dispose(bool disposing)
+        {
+            if (disposing)
+            {
+                failureMechanismObserver.Dispose();
+                sectionConfigurationsObserver.Dispose();
+            }
+        }
+
         private FailureMechanismSectionConfigurationProperties CreateFailureMechanismSectionConfigurationProperties(
             FailureMechanismSectionConfiguration sectionConfiguration,
             double sectionStart,
Index: Riskeer/Piping/src/Riskeer.Piping.Forms/PropertyClasses/PipingFailureMechanismSectionConfigurationsProperties.cs
===================================================================
diff -u -rba7b785c0fcda5936a3b76fe7f6d3a3aa598a91d -re0618171a8bece9ed88594171c5c824b7f4d44dd
--- Riskeer/Piping/src/Riskeer.Piping.Forms/PropertyClasses/PipingFailureMechanismSectionConfigurationsProperties.cs	(.../PipingFailureMechanismSectionConfigurationsProperties.cs)	(revision ba7b785c0fcda5936a3b76fe7f6d3a3aa598a91d)
+++ Riskeer/Piping/src/Riskeer.Piping.Forms/PropertyClasses/PipingFailureMechanismSectionConfigurationsProperties.cs	(.../PipingFailureMechanismSectionConfigurationsProperties.cs)	(revision e0618171a8bece9ed88594171c5c824b7f4d44dd)
@@ -109,10 +109,19 @@
 
         public void Dispose()
         {
-            failureMechanismObserver.Dispose();
-            sectionConfigurationsObserver.Dispose();
+            Dispose(true);
+            GC.SuppressFinalize(this);
         }
 
+        protected virtual void Dispose(bool disposing)
+        {
+            if (disposing)
+            {
+                failureMechanismObserver.Dispose();
+                sectionConfigurationsObserver.Dispose();
+            }
+        }
+
         private PipingFailureMechanismSectionConfigurationProperties CreateFailureMechanismSectionConfigurationProperties(
             PipingFailureMechanismSectionConfiguration sectionConfiguration,
             double sectionStart,