Index: Riskeer/Integration/src/Riskeer.Integration.IO/Helpers/HydraulicBoundaryLocationCalculationsExportHelper.cs
===================================================================
diff -u -r272cfc214b19eee23c9d875bc000a2b7a9a1a78e -rf15bd0f2220e15da0f793ffd112ec10edb66508f
--- Riskeer/Integration/src/Riskeer.Integration.IO/Helpers/HydraulicBoundaryLocationCalculationsExportHelper.cs	(.../HydraulicBoundaryLocationCalculationsExportHelper.cs)	(revision 272cfc214b19eee23c9d875bc000a2b7a9a1a78e)
+++ Riskeer/Integration/src/Riskeer.Integration.IO/Helpers/HydraulicBoundaryLocationCalculationsExportHelper.cs	(.../HydraulicBoundaryLocationCalculationsExportHelper.cs)	(revision f15bd0f2220e15da0f793ffd112ec10edb66508f)
@@ -22,6 +22,7 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Globalization;
 using System.IO;
 using System.Linq;
 using Core.Common.Util;
@@ -86,9 +87,10 @@
                                     ? Resources.WaterLevels_DisplayName
                                     : Resources.WaveHeights_DisplayName;
 
-            string uniqueName = NamingHelper.GetUniqueName(
-                exportedCalculationFileNames, $"{exportType}_{ReturnPeriodFormattingHelper.FormatFromProbability(targetProbability)}",
-                c => c);
+            string returnPeriod = ReturnPeriodFormattingHelper.FormatFromProbability(targetProbability)
+                                                              .ToString(CultureInfo.InvariantCulture)
+                                                              .Replace(".", "");
+            string uniqueName = NamingHelper.GetUniqueName(exportedCalculationFileNames, $"{exportType}_{returnPeriod}", c => c);
             exportedCalculationFileNames.Add(uniqueName);
 
             string tempFilePath = Path.Combine(folderPath, $"{uniqueName}.{RiskeerCommonIOResources.Shape_file_filter_Extension}");