Index: Riskeer/Piping/src/Riskeer.Piping.Data/Probabilistic/IPartialProbabilisticPipingOutput.cs
===================================================================
diff -u
--- Riskeer/Piping/src/Riskeer.Piping.Data/Probabilistic/IPartialProbabilisticPipingOutput.cs	(revision 0)
+++ Riskeer/Piping/src/Riskeer.Piping.Data/Probabilistic/IPartialProbabilisticPipingOutput.cs	(revision f975c003a5c9d480f85a9812cb579379b0c6e63d)
@@ -0,0 +1,47 @@
+// Copyright (C) Stichting Deltares 2019. All rights reserved.
+//
+// This file is part of Riskeer.
+//
+// Riskeer is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+//
+// All names, logos, and references to "Deltares" are registered trademarks of
+// Stichting Deltares and remain full property of Stichting Deltares at all times.
+// All rights reserved.
+
+using System;
+
+namespace Riskeer.Piping.Data.Probabilistic
+{
+    /// <summary>
+    /// Interface for the result of a sub-calculation for a <see cref="ProbabilisticPipingCalculation"/>.
+    /// </summary>
+    public interface IPartialProbabilisticPipingOutput : ICloneable
+
+    {
+    /// <summary>
+    /// Gets the reliability of the calculation.
+    /// </summary>
+    double Reliability { get; }
+
+    /// <summary>
+    /// Gets the value indicating whether the output contains a general result with illustration points.
+    /// </summary>
+    bool HasGeneralResult { get; }
+
+    /// <summary>
+    /// Clears the illustration points of the output.
+    /// </summary>
+    void ClearIllustrationPoints();
+    }
+}
\ No newline at end of file
Index: Riskeer/Piping/src/Riskeer.Piping.Data/Probabilistic/PartialProbabilisticPipingOutput.cs
===================================================================
diff -u -r984b298e426bd997cb17196b8d4e1a06f1395eb2 -rf975c003a5c9d480f85a9812cb579379b0c6e63d
--- Riskeer/Piping/src/Riskeer.Piping.Data/Probabilistic/PartialProbabilisticPipingOutput.cs	(.../PartialProbabilisticPipingOutput.cs)	(revision 984b298e426bd997cb17196b8d4e1a06f1395eb2)
+++ Riskeer/Piping/src/Riskeer.Piping.Data/Probabilistic/PartialProbabilisticPipingOutput.cs	(.../PartialProbabilisticPipingOutput.cs)	(revision f975c003a5c9d480f85a9812cb579379b0c6e63d)
@@ -27,7 +27,7 @@
     /// <summary>
     /// This class contains the result of a sub-calculation for a <see cref="ProbabilisticPipingCalculation"/>.
     /// </summary>
-    public class PartialProbabilisticPipingOutput : ICloneable
+    public class PartialProbabilisticPipingOutput : IPartialProbabilisticPipingOutput
     {
         /// <summary>
         /// Creates a new instance of <see cref="PartialProbabilisticPipingOutput"/>.
Index: Riskeer/Piping/test/Riskeer.Piping.Data.Test/Probabilistic/PartialProbabilisticPipingOutputTest.cs
===================================================================
diff -u -rd49838f35e7cb82cc5edc12795659dcaf0e08f29 -rf975c003a5c9d480f85a9812cb579379b0c6e63d
--- Riskeer/Piping/test/Riskeer.Piping.Data.Test/Probabilistic/PartialProbabilisticPipingOutputTest.cs	(.../PartialProbabilisticPipingOutputTest.cs)	(revision d49838f35e7cb82cc5edc12795659dcaf0e08f29)
+++ Riskeer/Piping/test/Riskeer.Piping.Data.Test/Probabilistic/PartialProbabilisticPipingOutputTest.cs	(.../PartialProbabilisticPipingOutputTest.cs)	(revision f975c003a5c9d480f85a9812cb579379b0c6e63d)
@@ -48,6 +48,7 @@
             var partialProbabilisticPipingOutput = new PartialProbabilisticPipingOutput(reliability, generalResult);
 
             // Assert
+            Assert.IsInstanceOf<IPartialProbabilisticPipingOutput>(partialProbabilisticPipingOutput);
             Assert.IsInstanceOf<ICloneable>(partialProbabilisticPipingOutput);
             Assert.AreEqual(reliability, partialProbabilisticPipingOutput.Reliability);
             Assert.AreEqual(withIllustrationPoints, partialProbabilisticPipingOutput.HasGeneralResult);