Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/OvertoppingCalculationWaveHeightParser.cs
===================================================================
diff -u -rc4466a8ed424027130055f128d89e8fc867582a4 -r6da3106d7e2d1fd132575370b20a73fcb5876eaf
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/OvertoppingCalculationWaveHeightParser.cs	(.../OvertoppingCalculationWaveHeightParser.cs)	(revision c4466a8ed424027130055f128d89e8fc867582a4)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/OvertoppingCalculationWaveHeightParser.cs	(.../OvertoppingCalculationWaveHeightParser.cs)	(revision 6da3106d7e2d1fd132575370b20a73fcb5876eaf)
@@ -83,7 +83,14 @@
         {
             try
             {
-                double waveHeight = Convert.ToDouble(result[waveHeightColumn]);
+                double waveHeight = double.NaN;
+                object waveHeightResult = result[waveHeightColumn];
+
+                if (waveHeightResult.GetType() != typeof(DBNull))   
+                {
+                    waveHeight = Convert.ToDouble(waveHeightResult);
+                }
+                
                 bool isOvertoppingDominant = Convert.ToBoolean(result[isOvertoppingDominantColumn]);
 
                 Output = new OvertoppingCalculationWaveHeightOutput(waveHeight,
Index: Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Parsers/OvertoppingCalculationWaveHeightParserTest.cs
===================================================================
diff -u -re6be1880f43a2fc660bdc08ca6ebe1a360393a3c -r6da3106d7e2d1fd132575370b20a73fcb5876eaf
--- Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Parsers/OvertoppingCalculationWaveHeightParserTest.cs	(.../OvertoppingCalculationWaveHeightParserTest.cs)	(revision e6be1880f43a2fc660bdc08ca6ebe1a360393a3c)
+++ Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Parsers/OvertoppingCalculationWaveHeightParserTest.cs	(.../OvertoppingCalculationWaveHeightParserTest.cs)	(revision 6da3106d7e2d1fd132575370b20a73fcb5876eaf)
@@ -186,5 +186,20 @@
             Assert.AreEqual(expectedWaveHeight, parser.Output.WaveHeight, 1e-11);
             Assert.AreEqual(expectedOvertoppingDominant, parser.Output.IsOvertoppingDominant);
         }
+
+        [Test]
+        public void Parse_WaveHeightNull_OutputSet()
+        {
+            // Setup
+            string path = Path.Combine(testDirectory, "ValidFileWaveHeightNull");
+            var parser = new OvertoppingCalculationWaveHeightParser();
+
+            // Call
+            parser.Parse(path, 1);
+
+            // Assert
+            Assert.IsNaN(parser.Output.WaveHeight);
+            Assert.IsFalse(parser.Output.IsOvertoppingDominant);
+        }
     }
 }
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