Index: Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Service/HeightStructuresCalculationActivity.cs
===================================================================
diff -u -r6ccc539ce58e63f0e0fbff0da189c87b65146129 -rd207738be4ce6f50f4e3e00839ea433acea10bbd
--- Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Service/HeightStructuresCalculationActivity.cs	(.../HeightStructuresCalculationActivity.cs)	(revision 6ccc539ce58e63f0e0fbff0da189c87b65146129)
+++ Ringtoets/HeightStructures/src/Ringtoets.HeightStructures.Service/HeightStructuresCalculationActivity.cs	(.../HeightStructuresCalculationActivity.cs)	(revision d207738be4ce6f50f4e3e00839ea433acea10bbd)
@@ -19,6 +19,7 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System;
 using System.Linq;
 using Core.Common.Base.Service;
 using Ringtoets.Common.Data.AssessmentSection;
@@ -54,9 +55,27 @@
         /// <param name="hlcdDirectory">The directory of the HLCD file that should be used for performing the calculation.</param>
         /// <param name="failureMechanism">The failure mechanism the calculation belongs to.</param>
         /// <param name="assessmentSection">The assessment section the calculation belongs to.</param>
+        /// <exception cref="ArgumentNullException">Thrown when any input argument is <c>null</c>.</exception>
         public HeightStructuresCalculationActivity(HeightStructuresCalculation calculation, string hlcdDirectory, 
                                                    HeightStructuresFailureMechanism failureMechanism, IAssessmentSection assessmentSection)
         {
+            if (calculation == null)
+            {
+                throw new ArgumentNullException("calculation");
+            }
+            if (hlcdDirectory == null)
+            {
+                throw new ArgumentNullException("hlcdDirectory");
+            }
+            if (failureMechanism == null)
+            {
+                throw new ArgumentNullException("failureMechanism");
+            }
+            if (assessmentSection == null)
+            {
+                throw new ArgumentNullException("assessmentSection");
+            }
+
             this.calculation = calculation;
             this.hlcdDirectory = hlcdDirectory;
             this.failureMechanism = failureMechanism;