Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/ExceedanceProbabilityCalculationParser.cs
===================================================================
diff -u -r3d9b418d483c122040e11a7e074d666c64e9d7b5 -r557c60f6aadb50bcb07503a0f5a1ea34ca6a3885
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/ExceedanceProbabilityCalculationParser.cs	(.../ExceedanceProbabilityCalculationParser.cs)	(revision 3d9b418d483c122040e11a7e074d666c64e9d7b5)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/ExceedanceProbabilityCalculationParser.cs	(.../ExceedanceProbabilityCalculationParser.cs)	(revision 557c60f6aadb50bcb07503a0f5a1ea34ca6a3885)
@@ -24,6 +24,7 @@
 using System.Data;
 using System.Data.SQLite;
 using System.IO;
+using Core.Common.Utils;
 using Ringtoets.HydraRing.Calculation.Data.Output;
 using Ringtoets.HydraRing.Calculation.Services;
 
@@ -54,6 +55,12 @@
 
         public void Parse(string workingDirectory, int sectionId)
         {
+            if (workingDirectory == null)
+            {
+                throw new ArgumentNullException("workingDirectory");
+            }
+            FileUtils.ValidateFilePath(workingDirectory);
+
             try
             {
                 Output = DoParse(Path.Combine(workingDirectory, HydraRingFileName.OutputDatabaseFileName), sectionId);