Index: Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingCalculation.cs
===================================================================
diff -u -rd320e912103d060e7a359846539a67dc54c616a4 -r314545f25db70366badcc527aeca68d241bfdcdc
--- Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingCalculation.cs	(.../PipingCalculation.cs)	(revision d320e912103d060e7a359846539a67dc54c616a4)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingCalculation.cs	(.../PipingCalculation.cs)	(revision 314545f25db70366badcc527aeca68d241bfdcdc)
@@ -21,6 +21,7 @@
 
 using System;
 using Core.Common.Base;
+using Ringtoets.Common.Data;
 using Ringtoets.Common.Data.FailureMechanism;
 using Ringtoets.Piping.Data.Properties;
 
@@ -29,7 +30,7 @@
     /// <summary>
     /// This class holds the information which can be made visible in the graphical interface of the application.
     /// </summary>
-    public class PipingCalculation : Observable, ICalculationItem, IPipingCalculationItem
+    public class PipingCalculation : Observable, ICalculationItem, ICalculation
     {
         /// <summary>
         /// Constructs a new instance of <see cref="PipingCalculation"/> with default values set for some of the parameters.
@@ -56,8 +57,6 @@
             SemiProbabilisticParameters = semiProbabilisticInputParameters;
         }
 
-        public string Comments { get; set; }
-
         /// <summary>
         /// Gets the parameters required to perform a semi-probabilistic assessment.
         /// </summary>
@@ -94,6 +93,8 @@
             }
         }
 
+        public string Comments { get; set; }
+
         public void ClearOutput()
         {
             Output = null;