Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/OvertoppingCalculationWaveHeightParser.cs
===================================================================
diff -u -rde19b11db1ed00aeb407dd9836db13b9a98e4316 -r557c60f6aadb50bcb07503a0f5a1ea34ca6a3885
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/OvertoppingCalculationWaveHeightParser.cs	(.../OvertoppingCalculationWaveHeightParser.cs)	(revision de19b11db1ed00aeb407dd9836db13b9a98e4316)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/OvertoppingCalculationWaveHeightParser.cs	(.../OvertoppingCalculationWaveHeightParser.cs)	(revision 557c60f6aadb50bcb07503a0f5a1ea34ca6a3885)
@@ -19,10 +19,12 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System;
 using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
 using System.Linq;
+using Core.Common.Utils;
 using Ringtoets.HydraRing.Calculation.Data.Output;
 using Ringtoets.HydraRing.Calculation.Services;
 
@@ -79,6 +81,12 @@
 
         public void Parse(string workingDirectory, int sectionId)
         {
+            if (workingDirectory == null)
+            {
+                throw new ArgumentNullException("workingDirectory");
+            }
+            FileUtils.ValidateFilePath(workingDirectory);
+
             string fileName = string.Format("{0}{1}", sectionId, HydraRingFileName.OutputFileSuffix);
             string filePath = Path.Combine(workingDirectory, fileName);