Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Calculator/DesignWaterLevelCalculator.cs
===================================================================
diff -u -r0fd23ff8e68b5f0d18d344d104bc68216cb49b51 -rb8d852df1bd7269388f44bcb13d23a51920842fc
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Calculator/DesignWaterLevelCalculator.cs	(.../DesignWaterLevelCalculator.cs)	(revision 0fd23ff8e68b5f0d18d344d104bc68216cb49b51)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Calculator/DesignWaterLevelCalculator.cs	(.../DesignWaterLevelCalculator.cs)	(revision b8d852df1bd7269388f44bcb13d23a51920842fc)
@@ -72,7 +72,14 @@
         public void CalculateWithIllustrationPoints(AssessmentLevelCalculationInput input)
         {
             includeIllustrationPoints = true;
-            Calculate(input);
+            try
+            {
+                Calculate(input);
+            }
+            finally
+            {
+                includeIllustrationPoints = false;
+            }
         }
 
         protected override IEnumerable<IHydraRingFileParser> GetParsers()
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Calculator/WaveHeightCalculator.cs
===================================================================
diff -u -r0fd23ff8e68b5f0d18d344d104bc68216cb49b51 -rb8d852df1bd7269388f44bcb13d23a51920842fc
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Calculator/WaveHeightCalculator.cs	(.../WaveHeightCalculator.cs)	(revision 0fd23ff8e68b5f0d18d344d104bc68216cb49b51)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Calculator/WaveHeightCalculator.cs	(.../WaveHeightCalculator.cs)	(revision b8d852df1bd7269388f44bcb13d23a51920842fc)
@@ -66,7 +66,14 @@
         public void CalculateWithIllustrationPoints(WaveHeightCalculationInput input)
         {
             includeIllustrationPoints = true;
-            Calculate(input);
+            try
+            {
+                Calculate(input);
+            }
+            finally
+            {
+                includeIllustrationPoints = false;
+            }
         }
 
         public void Calculate(WaveHeightCalculationInput input)
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/IllustrationPoints/IllustrationPointQueries.cs
===================================================================
diff -u -r2cfb421b8f27d648e22b13453ae1f2d9deb54f65 -rb8d852df1bd7269388f44bcb13d23a51920842fc
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/IllustrationPoints/IllustrationPointQueries.cs	(.../IllustrationPointQueries.cs)	(revision 2cfb421b8f27d648e22b13453ae1f2d9deb54f65)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/IllustrationPoints/IllustrationPointQueries.cs	(.../IllustrationPointQueries.cs)	(revision b8d852df1bd7269388f44bcb13d23a51920842fc)
@@ -26,9 +26,6 @@
     /// </summary>
     internal static class IllustrationPointQueries
     {
-        private const string firstPeriod = "PeriodId = (SELECT MIN(PeriodId) FROM GoverningWind)";
-        private const string lastIteration = "OuterIterationId = (SELECT MAX(OuterIterationId) FROM GoverningWind)";
-
         /// <summary>
         /// Selects all the closing situations.
         /// </summary>
@@ -38,13 +35,13 @@
             "FROM ClosingSituations;";
 
         /// <summary>
-        /// Selects all wind direction with a flag whether it is the wind direction is governing.
+        /// Selects all wind direction with a flag whether it the wind direction is governing.
         /// </summary>
         public static readonly string WindDirections =
             $"SELECT WindDirections.{IllustrationPointsDatabaseConstants.WindDirectionId}, " +
             $"{IllustrationPointsDatabaseConstants.WindDirectionName}, " +
             $"{IllustrationPointsDatabaseConstants.WindDirectionAngle}, " +
-            $"WindDirections.WindDirectionId = GoverningWind.WindDirectionId as {IllustrationPointsDatabaseConstants.IsGoverning} " +
+            $"WindDirections.WindDirectionId = GoverningWind.WindDirectionId AS {IllustrationPointsDatabaseConstants.IsGoverning} " +
             "FROM WindDirections " +
             "JOIN GoverningWind " +
             $"WHERE {lastIteration}" +
@@ -185,7 +182,7 @@
             $"{IllustrationPointsDatabaseConstants.RecursiveFaultTreeChildId}, " +
             $"{IllustrationPointsDatabaseConstants.RecursiveFaultTreeType}, " +
             $"{IllustrationPointsDatabaseConstants.RecursiveFaultTreeCombine}" +
-            ") AS(" +
+            ") AS (" +
             "SELECT FaultTreeId, Id1, Type1, CombinFunction " +
             "FROM FaultTrees " +
             "LEFT OUTER JOIN combineFunctions ON combineFunctions.id = Id1 " +
@@ -198,7 +195,7 @@
             $"{IllustrationPointsDatabaseConstants.RecursiveFaultTreeId}, " +
             $"{IllustrationPointsDatabaseConstants.RecursiveFaultTreeType}, " +
             $"{IllustrationPointsDatabaseConstants.RecursiveFaultTreeCombine}" +
-            ") AS(" +
+            ") AS (" +
             "SELECT null, " +
             "FaultTreeId, " +
             "\"faulttree\", " +
@@ -220,5 +217,8 @@
             $"{IllustrationPointsDatabaseConstants.RecursiveFaultTreeType}, " +
             $"{IllustrationPointsDatabaseConstants.RecursiveFaultTreeCombine} " +
             "FROM children;";
+
+        private const string firstPeriod = "PeriodId = (SELECT MIN(PeriodId) FROM GoverningWind)";
+        private const string lastIteration = "OuterIterationId = (SELECT MAX(OuterIterationId) FROM GoverningWind)";
     }
 }
\ No newline at end of file
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/IllustrationPoints/IllustrationPointsParser.cs
===================================================================
diff -u -r2cfb421b8f27d648e22b13453ae1f2d9deb54f65 -rb8d852df1bd7269388f44bcb13d23a51920842fc
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/IllustrationPoints/IllustrationPointsParser.cs	(.../IllustrationPointsParser.cs)	(revision 2cfb421b8f27d648e22b13453ae1f2d9deb54f65)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Parsers/IllustrationPoints/IllustrationPointsParser.cs	(.../IllustrationPointsParser.cs)	(revision b8d852df1bd7269388f44bcb13d23a51920842fc)
@@ -45,7 +45,6 @@
         private double beta = double.NaN;
         private WindDirection governingWindDirection;
         private IEnumerable<Stochast> stochasts;
-        private Dictionary<WindDirectionClosingSituation, IllustrationPointTreeNode> rootIllustrationPoints;
 
         private IDictionary<int, WindDirection> windDirections;
         private IDictionary<int, string> closingSituations;
@@ -115,16 +114,11 @@
             ProceedOrThrow(reader);
             ParseSubMechanismResults(reader);
             ProceedOrThrow(reader);
-            ParseFaultTree(reader);
-            if (rootIllustrationPoints == null)
-            {
-                SetSubMechanismAsRootIllustrationPoint();
-            }
+            Dictionary<WindDirectionClosingSituation, IllustrationPointTreeNode> rootIllustrationPoints =
+                ParseFaultTree(reader)
+                ?? GetSubMechanismAsRootIllustrationPoint();
 
-            if (governingWindDirection != null && stochasts != null && rootIllustrationPoints != null)
-            {
-                Output = new GeneralResult(beta, governingWindDirection, stochasts, rootIllustrationPoints);
-            }
+            Output = new GeneralResult(beta, governingWindDirection, stochasts, rootIllustrationPoints);
         }
 
         /// <summary>
@@ -140,39 +134,11 @@
             }
         }
 
-        private void SetSubMechanismAsRootIllustrationPoint()
-        {
-            rootIllustrationPoints = new Dictionary<WindDirectionClosingSituation, IllustrationPointTreeNode>();
-            foreach (Tuple<int, WindDirection, int, string> windDirectionClosingSituation in GetAllWindDirectionClosingSituationCombinations())
-            {
-                KeyValuePair<int, string> subMechanismIdName = subMechanisms.First();
-                string submechanismIllustrationPointName = subMechanismIdName.Value;
-
-                var key = new ThreeKeyIndex(windDirectionClosingSituation.Item1, windDirectionClosingSituation.Item3, subMechanismIdName.Key);
-
-                double subMechanismIllustrationPointBeta = subMechanismBetaValues[key];
-
-                var illustrationPointStochasts = new List<SubMechanismIllustrationPointStochast>();
-                AddRange(illustrationPointStochasts, subMechanismStochasts[key]);
-
-                var illustrationPointResults = new List<IllustrationPointResult>();
-                AddRange(illustrationPointResults, subMechanismResults[key]);
-
-                var illustrationPoint = new SubMechanismIllustrationPoint(submechanismIllustrationPointName,
-                                                                          illustrationPointStochasts,
-                                                                          illustrationPointResults,
-                                                                          subMechanismIllustrationPointBeta);
-
-                rootIllustrationPoints[CreateFaultTreeKey(windDirectionClosingSituation)] =
-                    new IllustrationPointTreeNode(illustrationPoint);
-            }
-        }
-
         /// <summary>
         /// Parses <see cref="Stochast"/> objects from the <paramref name="reader"/>.
         /// </summary>
         /// <param name="reader">The database reader.</param>
-        /// <exception cref="HydraRingFileParserException">Throw when the read <see cref="IllustrationPointsDatabaseConstants.AlphaValue"/>
+        /// <exception cref="HydraRingFileParserException">Thrown when the read <see cref="IllustrationPointsDatabaseConstants.AlphaValue"/>
         /// or <see cref="IllustrationPointsDatabaseConstants.Duration"/> is <see cref="DBNull"/>.</exception>
         private void ParseFaultTreeAlphaValues(HydraRingDatabaseReader reader)
         {
@@ -201,7 +167,7 @@
         /// Parses fault tree beta values from the <paramref name="reader"/>.
         /// </summary>
         /// <param name="reader">The database reader.</param>
-        /// <exception cref="HydraRingFileParserException">Throw when:
+        /// <exception cref="HydraRingFileParserException">Thrown when:
         /// <list type="bullet">
         /// <item>The read <see cref="IllustrationPointsDatabaseConstants.BetaValue"/> is <see cref="DBNull"/>;</item>
         /// <item>Multiple values for beta of illustration point found.</item>
@@ -229,7 +195,7 @@
         /// Parses <see cref="SubMechanismIllustrationPointStochast"/> objects from the <paramref name="reader"/>.
         /// </summary>
         /// <param name="reader">The database reader.</param>
-        /// <exception cref="HydraRingFileParserException">Throw when the read <see cref="IllustrationPointsDatabaseConstants.Duration"/>, 
+        /// <exception cref="HydraRingFileParserException">Thrown when the read <see cref="IllustrationPointsDatabaseConstants.Duration"/>, 
         /// <see cref="IllustrationPointsDatabaseConstants.AlphaValue"/>, or <see cref="IllustrationPointsDatabaseConstants.Realization"/>
         /// is <see cref="DBNull"/>.</exception>
         private void ParseSubMechanismAlphaValues(HydraRingDatabaseReader reader)
@@ -261,7 +227,7 @@
         /// Parses sub-mechanism beta values from the <paramref name="reader"/>.
         /// </summary>
         /// <param name="reader">The database reader.</param>
-        /// <exception cref="HydraRingFileParserException">Throw when:
+        /// <exception cref="HydraRingFileParserException">Thrown when:
         /// <list type="bullet">
         /// <item>The read <see cref="IllustrationPointsDatabaseConstants.BetaValue"/> is <see cref="DBNull"/>;</item>
         /// <item>Multiple values for beta of illustration point found.</item>
@@ -290,7 +256,7 @@
         /// Parses <see cref="IllustrationPointResult"/> objects from the <paramref name="reader"/>.
         /// </summary>
         /// <param name="reader">The database reader.</param>
-        /// <exception cref="HydraRingFileParserException">Throw when the read <see cref="IllustrationPointsDatabaseConstants.IllustrationPointResultValue"/> 
+        /// <exception cref="HydraRingFileParserException">Thrown when the read <see cref="IllustrationPointsDatabaseConstants.IllustrationPointResultValue"/> 
         /// is <see cref="DBNull"/>.</exception>
         private void ParseSubMechanismResults(HydraRingDatabaseReader reader)
         {
@@ -313,7 +279,7 @@
             }
         }
 
-        private void ParseFaultTree(HydraRingDatabaseReader reader)
+        private Dictionary<WindDirectionClosingSituation, IllustrationPointTreeNode> ParseFaultTree(HydraRingDatabaseReader reader)
         {
             IEnumerable<Tuple<int, WindDirection, int, string>> windDirectionClosingSituations =
                 GetAllWindDirectionClosingSituationCombinations();
@@ -323,17 +289,49 @@
             {
                 List<Tuple<int?, int, Type, CombinationType>> results = CreateResultTuples(readFaultTrees);
 
-                rootIllustrationPoints = new Dictionary<WindDirectionClosingSituation, IllustrationPointTreeNode>();
+                var rootIllustrationPoints = new Dictionary<WindDirectionClosingSituation, IllustrationPointTreeNode>();
                 foreach (Tuple<int, WindDirection, int, string> windDirectionClosingSituation in windDirectionClosingSituations)
                 {
                     Tuple<int?, int, Type, CombinationType> root = results.Single(r => !r.Item1.HasValue);
 
                     rootIllustrationPoints[CreateFaultTreeKey(windDirectionClosingSituation)] =
                         BuildFaultTree(windDirectionClosingSituation, root.Item2, root.Item4, results);
                 }
+                return rootIllustrationPoints;
             }
+            return null;
         }
 
+        private Dictionary<WindDirectionClosingSituation, IllustrationPointTreeNode> GetSubMechanismAsRootIllustrationPoint()
+        {
+            var rootIllustrationPoints = new Dictionary<WindDirectionClosingSituation, IllustrationPointTreeNode>();
+            foreach (Tuple<int, WindDirection, int, string> windDirectionClosingSituation in GetAllWindDirectionClosingSituationCombinations())
+            {
+                KeyValuePair<int, string> subMechanismIdName = subMechanisms.First();
+                string submechanismIllustrationPointName = subMechanismIdName.Value;
+
+                var key = new ThreeKeyIndex(windDirectionClosingSituation.Item1, windDirectionClosingSituation.Item3, subMechanismIdName.Key);
+
+                double subMechanismIllustrationPointBeta = subMechanismBetaValues[key];
+
+                var illustrationPointStochasts = new List<SubMechanismIllustrationPointStochast>();
+                AddRange(illustrationPointStochasts, subMechanismStochasts[key]);
+
+                var illustrationPointResults = new List<IllustrationPointResult>();
+                AddRange(illustrationPointResults, subMechanismResults[key]);
+
+                var illustrationPoint = new SubMechanismIllustrationPoint(submechanismIllustrationPointName,
+                                                                          illustrationPointStochasts,
+                                                                          illustrationPointResults,
+                                                                          subMechanismIllustrationPointBeta);
+
+                rootIllustrationPoints[CreateFaultTreeKey(windDirectionClosingSituation)] =
+                    new IllustrationPointTreeNode(illustrationPoint);
+            }
+
+            return rootIllustrationPoints;
+        }
+
         private static List<Tuple<int?, int, Type, CombinationType>> CreateResultTuples(Dictionary<string, object>[] readFaultTrees)
         {
             var results = new List<Tuple<int?, int, Type, CombinationType>>();
@@ -438,7 +436,7 @@
         /// Parses beta values from the <paramref name="reader"/>.
         /// </summary>
         /// <param name="reader">The database reader.</param>
-        /// <exception cref="HydraRingFileParserException">Throw when:
+        /// <exception cref="HydraRingFileParserException">Thrown when:
         /// <list type="bullet">
         /// <item>The read <see cref="IllustrationPointsDatabaseConstants.BetaValue"/> is <see cref="DBNull"/>;</item>
         /// <item>Multiple values for beta of illustration point found.</item>
@@ -465,7 +463,7 @@
         /// <param name="doubleValue">The object to convert.</param>
         /// <param name="identifier">The identifier.</param>
         /// <returns>The converted double.</returns>
-        /// <exception cref="HydraRingFileParserException">Throw when <paramref name="doubleValue"/> 
+        /// <exception cref="HydraRingFileParserException">Thrown when <paramref name="doubleValue"/> 
         /// is <see cref="DBNull"/>.</exception>
         /// <seealso cref="Convert.ToDouble(object)"/>
         private static double ConvertToDouble(object doubleValue, string identifier)
@@ -481,7 +479,7 @@
         /// Parses <see cref="Stochast"/> objects from the <paramref name="reader"/>.
         /// </summary>
         /// <param name="reader">The database reader.</param>
-        /// <exception cref="HydraRingFileParserException">Throw when the read <see cref="IllustrationPointsDatabaseConstants.Duration"/> 
+        /// <exception cref="HydraRingFileParserException">Thrown when the read <see cref="IllustrationPointsDatabaseConstants.Duration"/> 
         /// or <see cref="IllustrationPointsDatabaseConstants.AlphaValue"/> is <see cref="DBNull"/>.</exception>
         private void ParseGeneralAlphaValues(HydraRingDatabaseReader reader)
         {
@@ -505,8 +503,8 @@
         /// Parses <see cref="WindDirection"/> objects from the <paramref name="reader"/>.
         /// </summary>
         /// <param name="reader">The database reader.</param>
-        /// <exception cref="HydraRingFileParserException">Throw when the read <see cref="IllustrationPointsDatabaseConstants.WindDirectionAngle"/> 
-        /// is <see cref="DBNull"/>.</exception>
+        /// <exception cref="HydraRingFileParserException">Thrown when the read <see cref="IllustrationPointsDatabaseConstants.WindDirectionAngle"/> 
+        /// is <see cref="DBNull"/> or when no governing wind direction is found.</exception>
         private void ParseWindDirections(HydraRingDatabaseReader reader)
         {
             windDirections = new Dictionary<int, WindDirection>();
@@ -527,6 +525,11 @@
                     governingWindDirection = windDirection;
                 }
             }
+
+            if (governingWindDirection == null)
+            {
+                throw new HydraRingFileParserException(Resources.IllustrationPointsParser_Parse_No_governing_wind_direction_found);
+            }
         }
 
         private void ParseSubMechanisms(HydraRingDatabaseReader reader)
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Properties/Resources.Designer.cs
===================================================================
diff -u -r2cfb421b8f27d648e22b13453ae1f2d9deb54f65 -rb8d852df1bd7269388f44bcb13d23a51920842fc
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 2cfb421b8f27d648e22b13453ae1f2d9deb54f65)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision b8d852df1bd7269388f44bcb13d23a51920842fc)
@@ -167,6 +167,16 @@
         }
         
         /// <summary>
+        ///   Looks up a localized string similar to Er is geen maatgevende windrichting gevonden in de uitvoer database..
+        /// </summary>
+        internal static string IllustrationPointsParser_Parse_No_governing_wind_direction_found {
+            get {
+                return ResourceManager.GetString("IllustrationPointsParser_ParseWindDirections_Er_is_geen_maatgevende_windrichting_" +
+                        "gevonden_in_de_uitvoer_database_", resourceCulture);
+            }
+        }
+        
+        /// <summary>
         ///   Looks up a localized string similar to Er is geen resultaat voor overslag en overloop gevonden in de Hydra-Ring uitvoerdatabase..
         /// </summary>
         internal static string OvertoppingCalculationWaveHeightParser_No_overtopping_found_in_output_file {
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Properties/Resources.resx
===================================================================
diff -u -r2cfb421b8f27d648e22b13453ae1f2d9deb54f65 -rb8d852df1bd7269388f44bcb13d23a51920842fc
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Properties/Resources.resx	(.../Resources.resx)	(revision 2cfb421b8f27d648e22b13453ae1f2d9deb54f65)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Properties/Resources.resx	(.../Resources.resx)	(revision b8d852df1bd7269388f44bcb13d23a51920842fc)
@@ -160,4 +160,7 @@
     <value>Het besturingssysteem geeft de volgende melding:
 {0}</value>
   </data>
+  <data name="IllustrationPointsParser_ParseWindDirections_Er_is_geen_maatgevende_windrichting_gevonden_in_de_uitvoer_database_" xml:space="preserve">
+    <value>Er is geen maatgevende windrichting gevonden in de uitvoer database.</value>
+  </data>
 </root>
\ No newline at end of file
Index: Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Parsers/IllustrationPoints/IllustrationPointsParserTest.cs
===================================================================
diff -u -r2cfb421b8f27d648e22b13453ae1f2d9deb54f65 -rb8d852df1bd7269388f44bcb13d23a51920842fc
--- Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Parsers/IllustrationPoints/IllustrationPointsParserTest.cs	(.../IllustrationPointsParserTest.cs)	(revision 2cfb421b8f27d648e22b13453ae1f2d9deb54f65)
+++ Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Parsers/IllustrationPoints/IllustrationPointsParserTest.cs	(.../IllustrationPointsParserTest.cs)	(revision b8d852df1bd7269388f44bcb13d23a51920842fc)
@@ -147,6 +147,21 @@
         }
 
         [Test]
+        public void Parse_NoGoverningWindDirection_ThrowsHydraRingFileParserException()
+        {
+            // Setup
+            string path = Path.Combine(testDirectory, "NoGoverningWindDirection");
+            var parser = new IllustrationPointsParser();
+
+            // Call
+            TestDelegate test = () => parser.Parse(path, 1);
+
+            // Assert
+            var exception = Assert.Throws<HydraRingFileParserException>(test);
+            Assert.AreEqual("Er is geen maatgevende windrichting gevonden in de uitvoer database.", exception.Message);
+        }
+
+        [Test]
         [TestCase(nameof(IllustrationPointsDatabaseConstants.AlphaValue), IllustrationPointsDatabaseConstants.AlphaValue)]
         [TestCase(nameof(IllustrationPointsDatabaseConstants.BetaValue), IllustrationPointsDatabaseConstants.BetaValue)]
         [TestCase(nameof(IllustrationPointsDatabaseConstants.Duration), IllustrationPointsDatabaseConstants.Duration)]
Index: Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/test-data/Parsers/IllustrationPointsParser/NoGoverningWindDirection/1-output.sqlite
===================================================================
diff -u
Binary files differ