Index: Riskeer/ClosingStructures/src/Riskeer.ClosingStructures.Plugin/ClosingStructuresPlugin.cs
===================================================================
diff -u -rd8bd61b7bc08c01d7965635f028a227d0425d120 -r7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df
--- Riskeer/ClosingStructures/src/Riskeer.ClosingStructures.Plugin/ClosingStructuresPlugin.cs	(.../ClosingStructuresPlugin.cs)	(revision d8bd61b7bc08c01d7965635f028a227d0425d120)
+++ Riskeer/ClosingStructures/src/Riskeer.ClosingStructures.Plugin/ClosingStructuresPlugin.cs	(.../ClosingStructuresPlugin.cs)	(revision 7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df)
@@ -923,7 +923,7 @@
                 RiskeerCommonIOResources.Shape_file_filter_Description);
         }
 
-        private bool VerifyStructuresShouldUpdate(IFailureMechanism failureMechanism, string query)
+        private bool VerifyStructuresShouldUpdate(ClosingStructuresFailureMechanism failureMechanism, string query)
         {
             var changeHandler = new FailureMechanismCalculationChangeHandler(failureMechanism, query, GetInquiryHelper());
             return !changeHandler.RequireConfirmation() || changeHandler.InquireConfirmation();
Index: Riskeer/Common/src/Riskeer.Common.Data/FailureMechanism/ICalculatableFailureMechanism.cs
===================================================================
diff -u -r96ccefa48aa5c97c949f7a7858fcb4d3dc727a3a -r7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df
--- Riskeer/Common/src/Riskeer.Common.Data/FailureMechanism/ICalculatableFailureMechanism.cs	(.../ICalculatableFailureMechanism.cs)	(revision 96ccefa48aa5c97c949f7a7858fcb4d3dc727a3a)
+++ Riskeer/Common/src/Riskeer.Common.Data/FailureMechanism/ICalculatableFailureMechanism.cs	(.../ICalculatableFailureMechanism.cs)	(revision 7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df)
@@ -19,16 +19,23 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System.Collections.Generic;
 using Riskeer.Common.Data.Calculation;
 
 namespace Riskeer.Common.Data.FailureMechanism
 {
     /// <summary>
     /// Interface describing a failure mechanism that contains calculation groups that contains calculations.
     /// </summary>
-    public interface ICalculatableFailureMechanism
+    public interface ICalculatableFailureMechanism : IFailureMechanism
     {
         /// <summary>
+        /// Gets an <see cref="IEnumerable{T}"/> of all the <see cref="ICalculation"/> instances added to
+        /// the failure mechanism.
+        /// </summary>
+        IEnumerable<ICalculation> Calculations { get; }
+        
+        /// <summary>
         /// Gets all available calculation groups.
         /// </summary>
         CalculationGroup CalculationsGroup { get; }
Index: Riskeer/Common/src/Riskeer.Common.Data/FailureMechanism/IFailureMechanism.cs
===================================================================
diff -u -r838294dfe4b1f8026e2f16d8f992940ea29dd36d -r7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df
--- Riskeer/Common/src/Riskeer.Common.Data/FailureMechanism/IFailureMechanism.cs	(.../IFailureMechanism.cs)	(revision 838294dfe4b1f8026e2f16d8f992940ea29dd36d)
+++ Riskeer/Common/src/Riskeer.Common.Data/FailureMechanism/IFailureMechanism.cs	(.../IFailureMechanism.cs)	(revision 7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df)
@@ -19,8 +19,6 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
-using System.Collections.Generic;
-using Riskeer.Common.Data.Calculation;
 using Riskeer.Common.Data.FailurePath;
 
 namespace Riskeer.Common.Data.FailureMechanism
@@ -31,12 +29,6 @@
     public interface IFailureMechanism : IFailurePath
     {
         /// <summary>
-        /// Gets an <see cref="IEnumerable{T}"/> of all the <see cref="ICalculation"/> instances added to
-        /// the failure mechanism.
-        /// </summary>
-        IEnumerable<ICalculation> Calculations { get; }
-        
-        /// <summary>
         /// Gets the input comments associated with the calculations of the data object.
         /// </summary>
         Comment CalculationsInputComments { get; }
Index: Riskeer/Common/src/Riskeer.Common.Data/Structures/StructuresFailureMechanismAssemblyFactory.cs
===================================================================
diff -u -rec2c838182ed237b3abd753347a861857129331b -r7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df
--- Riskeer/Common/src/Riskeer.Common.Data/Structures/StructuresFailureMechanismAssemblyFactory.cs	(.../StructuresFailureMechanismAssemblyFactory.cs)	(revision ec2c838182ed237b3abd753347a861857129331b)
+++ Riskeer/Common/src/Riskeer.Common.Data/Structures/StructuresFailureMechanismAssemblyFactory.cs	(.../StructuresFailureMechanismAssemblyFactory.cs)	(revision 7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df)
@@ -45,7 +45,7 @@
         /// <exception cref="ArgumentNullException">Thrown when any argument is <c>null</c>.</exception>
         /// <exception cref="AssemblyException">Thrown when the section could not be assembled.</exception>
         public static FailureMechanismSectionAssemblyResult AssembleSection<TStructuresInput>(AdoptableFailureMechanismSectionResult sectionResult,
-                                                                                              IFailureMechanism failureMechanism,
+                                                                                              ICalculatableFailureMechanism failureMechanism,
                                                                                               IAssessmentSection assessmentSection)
             where TStructuresInput : IStructuresCalculationInput<StructureBase>, new()
         {
Index: Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/FailureMechanismCalculationChangeHandler.cs
===================================================================
diff -u -ref9f41ef150aee02d286c53de24660a19d948e02 -r7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df
--- Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/FailureMechanismCalculationChangeHandler.cs	(.../FailureMechanismCalculationChangeHandler.cs)	(revision ef9f41ef150aee02d286c53de24660a19d948e02)
+++ Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/FailureMechanismCalculationChangeHandler.cs	(.../FailureMechanismCalculationChangeHandler.cs)	(revision 7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df)
@@ -43,7 +43,7 @@
         /// <param name="query">The query which should be displayed when inquiring for a confirmation.</param>
         /// <param name="inquiryHandler">Object responsible for inquiring required data.</param>
         /// <exception cref="ArgumentNullException">Thrown when any input parameter is <c>null</c>.</exception>
-        public FailureMechanismCalculationChangeHandler(IFailureMechanism failureMechanism,
+        public FailureMechanismCalculationChangeHandler(ICalculatableFailureMechanism failureMechanism,
                                                         string query,
                                                         IInquiryHelper inquiryHandler)
         {
@@ -78,8 +78,8 @@
         }
 
         /// <summary>
-        /// Gets the <see cref="IFailureMechanism"/>.
+        /// Gets the <see cref="ICalculatableFailureMechanism"/>.
         /// </summary>
-        protected IFailureMechanism FailureMechanism { get; }
+        protected ICalculatableFailureMechanism FailureMechanism { get; }
     }
 }
\ No newline at end of file
Index: Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/FailureMechanismPropertyChangeHandler.cs
===================================================================
diff -u -r96ccefa48aa5c97c949f7a7858fcb4d3dc727a3a -r7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df
--- Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/FailureMechanismPropertyChangeHandler.cs	(.../FailureMechanismPropertyChangeHandler.cs)	(revision 96ccefa48aa5c97c949f7a7858fcb4d3dc727a3a)
+++ Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/FailureMechanismPropertyChangeHandler.cs	(.../FailureMechanismPropertyChangeHandler.cs)	(revision 7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df)
@@ -36,7 +36,8 @@
     /// Class which properly handles data model changes due to a change of a
     /// failure mechanism property.
     /// </summary>
-    public class FailureMechanismPropertyChangeHandler<T> : IFailureMechanismPropertyChangeHandler<T> where T : IFailureMechanism
+    public class FailureMechanismPropertyChangeHandler<T> : IFailureMechanismPropertyChangeHandler<T>
+        where T : ICalculatableFailureMechanism
     {
         public IEnumerable<IObservable> SetPropertyValueAfterConfirmation<TValue>(
             T failureMechanism,
Index: Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/IFailureMechanismPropertyChangeHandler.cs
===================================================================
diff -u -r96ccefa48aa5c97c949f7a7858fcb4d3dc727a3a -r7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df
--- Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/IFailureMechanismPropertyChangeHandler.cs	(.../IFailureMechanismPropertyChangeHandler.cs)	(revision 96ccefa48aa5c97c949f7a7858fcb4d3dc727a3a)
+++ Riskeer/Common/src/Riskeer.Common.Forms/PropertyClasses/IFailureMechanismPropertyChangeHandler.cs	(.../IFailureMechanismPropertyChangeHandler.cs)	(revision 7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df)
@@ -29,20 +29,20 @@
     /// <summary>
     /// Action in which a property of the <paramref name="failureMechanism"/> is set to the given <paramref name="value"/>.
     /// </summary>
-    /// <typeparam name="TFailureMechanism">The type of the failure mechanism that is passed as argument.</typeparam>
+    /// <typeparam name="TFailureMechanism">The type of the calculatable failure mechanism that is passed as argument.</typeparam>
     /// <typeparam name="TValue">The type of the value that is set on a property of the failure mechanism.</typeparam>
     /// <param name="failureMechanism">The failure mechanism for which the property will be set.</param>
     /// <param name="value">The new value of the failure mechanism property.</param>
     /// <exception cref="Exception">Thrown when setting the property value results in an exception being thrown.</exception>
     public delegate void SetFailureMechanismPropertyValueDelegate<in TFailureMechanism, in TValue>(TFailureMechanism failureMechanism, TValue value)
-        where TFailureMechanism : IFailureMechanism;
+        where TFailureMechanism : ICalculatableFailureMechanism;
 
     /// <summary>
     /// Interface for an object that can properly handle data model changes due to a change of a
     /// failure mechanism property.
     /// </summary>
-    /// <typeparam name="T">The type of the failure mechanism.</typeparam>
-    public interface IFailureMechanismPropertyChangeHandler<T> where T : IFailureMechanism
+    /// <typeparam name="T">The type of the calculatable failure mechanism.</typeparam>
+    public interface IFailureMechanismPropertyChangeHandler<T> where T : ICalculatableFailureMechanism
     {
         /// <summary>
         /// Find out whether the property can be updated with or without confirmation. If confirmation is required, 
Index: Riskeer/Common/src/Riskeer.Common.Forms/TreeNodeInfos/RiskeerContextMenuItemFactory.cs
===================================================================
diff -u -r3192f0b781afb4da048556c46e1b78c4079d05e4 -r7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df
--- Riskeer/Common/src/Riskeer.Common.Forms/TreeNodeInfos/RiskeerContextMenuItemFactory.cs	(.../RiskeerContextMenuItemFactory.cs)	(revision 3192f0b781afb4da048556c46e1b78c4079d05e4)
+++ Riskeer/Common/src/Riskeer.Common.Forms/TreeNodeInfos/RiskeerContextMenuItemFactory.cs	(.../RiskeerContextMenuItemFactory.cs)	(revision 7fe371dd6b57c27b2a41f73b942a57f9e9a6e8df)
@@ -298,7 +298,7 @@
         /// </summary>
         /// <param name="failureMechanism">The failure mechanism to clear the output for.</param>
         /// <returns>The created <see cref="StrictContextMenuItem"/>.</returns>
-        public static StrictContextMenuItem CreateClearAllCalculationOutputInFailureMechanismItem(IFailureMechanism failureMechanism)
+        public static StrictContextMenuItem CreateClearAllCalculationOutputInFailureMechanismItem(ICalculatableFailureMechanism failureMechanism)
         {
             var clearAllItem = new StrictContextMenuItem(
                 Resources.Clear_all_output,
@@ -330,7 +330,7 @@
             TFailureMechanismContext failureMechanismContext,
             Action<TFailureMechanismContext> calculateAllAction,
             Func<TFailureMechanismContext, string> enableMenuItemFunction)
-            where TFailureMechanismContext : IFailurePathContext<IFailureMechanism>
+            where TFailureMechanismContext : IFailurePathContext<ICalculatableFailureMechanism>
         {
             var menuItem = new StrictContextMenuItem(
                 Resources.Calculate_All,
@@ -365,7 +365,7 @@
             TFailureMechanismContext failureMechanism,
             Action<TFailureMechanismContext> validateAllAction,
             Func<TFailureMechanismContext, string> enableMenuItemFunction)
-            where TFailureMechanismContext : IFailurePathContext<IFailureMechanism>
+            where TFailureMechanismContext : IFailurePathContext<ICalculatableFailureMechanism>
         {
             var menuItem = new StrictContextMenuItem(
                 Resources.Validate_All,
@@ -643,7 +643,7 @@
             }
         }
 
-        private static void ClearAllCalculationOutputInFailureMechanism(IFailureMechanism failureMechanism)
+        private static void ClearAllCalculationOutputInFailureMechanism(ICalculatableFailureMechanism failureMechanism)
         {
             if (MessageBox.Show(Resources.FailureMechanism_ContextMenuStrip_Are_you_sure_clear_all_output, BaseResources.Confirm, MessageBoxButtons.OKCancel) != DialogResult.OK)
             {