Index: dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.Designer.cs
===================================================================
diff -u -r376 -r797
--- dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 376)
+++ dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 797)
@@ -61,6 +61,33 @@
         }
         
         /// <summary>
+        ///   Looks up a localized string similar to Parameter {0} is not a number (NaN)..
+        /// </summary>
+        internal static string PipingCalculatorSellmeijerVNK_LogParameterIsNaN_NaNParameterError {
+            get {
+                return ResourceManager.GetString("PipingCalculatorSellmeijerVNK_LogParameterIsNaN_NaNParameterError", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to HRiver - HExit may not be 0..
+        /// </summary>
+        internal static string PipingCalculatorSellmeijerVNK_PerformValidate_HRiver_HExit_Zero {
+            get {
+                return ResourceManager.GetString("PipingCalculatorSellmeijerVNK_PerformValidate_HRiver_HExit_Zero", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to Rc may not be less than 0..
+        /// </summary>
+        internal static string PipingCalculatorSellmeijerVNK_PerformValidate_RcLessThan0 {
+            get {
+                return ResourceManager.GetString("PipingCalculatorSellmeijerVNK_PerformValidate_RcLessThan0", resourceCulture);
+            }
+        }
+        
+        /// <summary>
         ///   Looks up a localized string similar to Error in Piping DLL.
         /// </summary>
         internal static string PipingModel2Calculation_CalculateHeadDropPC2_Error_in_Piping_DLL {
Index: dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.nl-NL.resx
===================================================================
diff -u -r376 -r797
--- dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.nl-NL.resx	(.../Resources.nl-NL.resx)	(revision 376)
+++ dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.nl-NL.resx	(.../Resources.nl-NL.resx)	(revision 797)
@@ -117,6 +117,15 @@
   <resheader name="writer">
     <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
   </resheader>
+  <data name="PipingCalculatorSellmeijerVNK_LogParameterIsNaN_NaNParameterError" xml:space="preserve">
+    <value>Parameter {0} heeft geen waarde (NaN).</value>
+  </data>
+  <data name="PipingCalculatorSellmeijerVNK_PerformValidate_HRiver_HExit_Zero" xml:space="preserve">
+    <value>De term HRiver - HExit mag niet nul zijn.</value>
+  </data>
+  <data name="PipingCalculatorSellmeijerVNK_PerformValidate_RcLessThan0" xml:space="preserve">
+    <value>De waarde voor de dempingsfactor mag niet lager dan 0 zijn.</value>
+  </data>
   <data name="PipingModel2Calculation_CalculateHeadDropPC2_Error_in_Piping_DLL" xml:space="preserve">
     <value>Er is een fout opgetreden in PipingCalc2.dll</value>
   </data>
Index: dam failuremechanisms/damPiping/trunk/src/Tests/Deltares.DamPiping.SellmeijerVNKCalculatorTests/PipingCalculatorSellmeijerVNKTest.cs
===================================================================
diff -u -r391 -r797
--- dam failuremechanisms/damPiping/trunk/src/Tests/Deltares.DamPiping.SellmeijerVNKCalculatorTests/PipingCalculatorSellmeijerVNKTest.cs	(.../PipingCalculatorSellmeijerVNKTest.cs)	(revision 391)
+++ dam failuremechanisms/damPiping/trunk/src/Tests/Deltares.DamPiping.SellmeijerVNKCalculatorTests/PipingCalculatorSellmeijerVNKTest.cs	(.../PipingCalculatorSellmeijerVNKTest.cs)	(revision 797)
@@ -161,6 +161,8 @@
             reducedFall = calculator.GetReducedFall();
             Assert.AreEqual(2.00, reducedFall, cTolerance);
         }
+
+        [Test]
         public void TestDetermineFactorOfSafety()
         {
             // foSp = hc / reducedFall
@@ -207,5 +209,131 @@
             calculator.Calculate();
         }
 
+        [Test]
+        public void TestValidateNaNParameter()
+        {
+            var calculator = new PipingCalculatorSellmeijerVNK
+            {
+                HRiver = 1.0,
+                HExit = 0.0,
+                PolderLevel = 0.0,
+                SurfaceLevel = 0.0,
+                Rc = 0.3,
+                DTotal = 2.0,
+                DInBetweenAquiferlayer = 2.0,
+                DBottomAquiferlayer = 6.0,
+                PermeabilityInBetweenAquiferlayer = 0.0001,
+                PermeabilityBottomAquiferlayer = 0.0002,
+                SeepageLength = 40.5,
+                D70 = 200.0,
+                WhitesConstant = 0.25,
+                BeddingAngle = 37.0,
+                WaterViscosity = 1.33E-06,
+            };
+            var originalErrors = calculator.Validate();
+
+            calculator.HRiver = double.NaN;
+            calculator.HExit = double.NaN;
+            calculator.PolderLevel = double.NaN;
+            calculator.SurfaceLevel = double.NaN;
+            calculator.Rc = double.NaN;
+            calculator.DTotal = double.NaN;
+            calculator.DInBetweenAquiferlayer = double.NaN;
+            calculator.DBottomAquiferlayer = double.NaN;
+            calculator.PermeabilityInBetweenAquiferlayer = double.NaN;
+            calculator.PermeabilityBottomAquiferlayer = double.NaN;
+            calculator.SeepageLength = double.NaN;
+            calculator.D70 = double.NaN;
+            calculator.WhitesConstant = double.NaN;
+            calculator.BeddingAngle = double.NaN;
+            calculator.WaterViscosity = double.NaN;
+            var nanErrors = calculator.Validate();
+            Assert.AreEqual(originalErrors.Count + 15, nanErrors.Count);
+        }
+
+        [Test]
+        [SetUICulture("en-US")]
+        public void TestValidateRcLessThan0En()
+        {
+            var calculator = new PipingCalculatorSellmeijerVNK
+            {
+                HRiver = 1.0,
+                HExit = 0.0,
+                PolderLevel = 0.0,
+                SurfaceLevel = 0.0,
+                Rc = -1e-6,
+                DTotal = 2.0,
+                DInBetweenAquiferlayer = 2.0,
+                DBottomAquiferlayer = 6.0,
+                PermeabilityInBetweenAquiferlayer = 0.0001,
+                PermeabilityBottomAquiferlayer = 0.0002,
+                SeepageLength = 40.5,
+                D70 = 200.0,
+                WhitesConstant = 0.25,
+                BeddingAngle = 37.0,
+                WaterViscosity = 1.33E-06,
+            };
+            var errors = calculator.Validate();
+            Assert.AreEqual(1, errors.Count);
+            var expectedMessageEN = "Rc may not be less than 0.";
+            CollectionAssert.AreEqual(new[] { expectedMessageEN }, errors);
+        }
+
+        [Test]
+        [SetUICulture("nl-NL")]
+        public void TestValidateRcLessThan0Nl()
+        {
+            var calculator = new PipingCalculatorSellmeijerVNK
+            {
+                HRiver = 1.0,
+                HExit = 0.0,
+                PolderLevel = 0.0,
+                SurfaceLevel = 0.0,
+                Rc = -1e-6,
+                DTotal = 2.0,
+                DInBetweenAquiferlayer = 2.0,
+                DBottomAquiferlayer = 6.0,
+                PermeabilityInBetweenAquiferlayer = 0.0001,
+                PermeabilityBottomAquiferlayer = 0.0002,
+                SeepageLength = 40.5,
+                D70 = 200.0,
+                WhitesConstant = 0.25,
+                BeddingAngle = 37.0,
+                WaterViscosity = 1.33E-06,
+            };
+            var errors = calculator.Validate();
+            Assert.AreEqual(1, errors.Count);
+            var expectedMessageNL = "De waarde voor de dempingsfactor mag niet lager dan 0 zijn.";
+            CollectionAssert.AreEqual(new[] { expectedMessageNL }, errors);
+        }
+
+        [Test]
+        [SetUICulture("nl-NL")]
+        public void TestValidateReducedFall()
+        {
+            var calculator = new PipingCalculatorSellmeijerVNK
+            {
+                HRiver = 1.0,
+                HExit = 1.0,
+                PolderLevel = 0.0,
+                SurfaceLevel = 0.0,
+                Rc = 0,
+                DTotal = 2.0,
+                DInBetweenAquiferlayer = 2.0,
+                DBottomAquiferlayer = 6.0,
+                PermeabilityInBetweenAquiferlayer = 0.0001,
+                PermeabilityBottomAquiferlayer = 0.0002,
+                SeepageLength = 40.5,
+                D70 = 200.0,
+                WhitesConstant = 0.25,
+                BeddingAngle = 37.0,
+                WaterViscosity = 1.33E-06,
+            };
+            var errors = calculator.Validate();
+            Assert.AreEqual(1, errors.Count);
+            var expectedMessageEN = "De term HRiver - HExit mag niet nul zijn.";
+            CollectionAssert.AreEqual(new[] { expectedMessageEN }, errors);
+        }
+
     }
 }
Index: dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/PipingCalculatorSellmeijerVNK.cs
===================================================================
diff -u -r397 -r797
--- dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/PipingCalculatorSellmeijerVNK.cs	(.../PipingCalculatorSellmeijerVNK.cs)	(revision 397)
+++ dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/PipingCalculatorSellmeijerVNK.cs	(.../PipingCalculatorSellmeijerVNK.cs)	(revision 797)
@@ -2,6 +2,7 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using Deltares.DamPiping.SellmeijerVNKCalculator.Properties;
 
 namespace Deltares.DamPiping.SellmeijerVNKCalculator
 {
@@ -193,5 +194,96 @@
             // Kx or Ky: Sel: Use Kx
         }
 
+        /// <summary>
+        /// Validates the input
+        /// </summary>
+        /// <returns>a filled list when errors are found else an empty list</returns>
+        public List<string> Validate()
+        {
+            var errors = new List<string>();
+            errors.AddRange(PerformValidate());
+            return errors;
+        }
+
+        private List<string> PerformValidate()
+        {
+            var errors = new List<string>();
+            if (Math.Abs(GetReducedFall()) < double.Epsilon)
+            {
+                errors.Add(Resources.PipingCalculatorSellmeijerVNK_PerformValidate_HRiver_HExit_Zero);
+            }
+
+            if (double.IsNaN(SeepageLength))
+            {
+                LogParameterIsNaN(errors, "SeepageLength");
+            }
+            if (double.IsNaN(HRiver))
+            {
+                LogParameterIsNaN(errors, "HRiver");
+            }
+            if (double.IsNaN(PolderLevel))
+            {
+                LogParameterIsNaN(errors, "PolderLevel");
+            }
+            if (double.IsNaN(SurfaceLevel))
+            {
+                LogParameterIsNaN(errors, "SurfaceLevel");
+            }
+            if (double.IsNaN(Rc))
+            {
+                LogParameterIsNaN(errors, "Rc");
+            }
+            if (Rc < 0)
+            {
+                errors.Add(Resources.PipingCalculatorSellmeijerVNK_PerformValidate_RcLessThan0);
+            }
+            if (double.IsNaN(DTotal))
+            {
+                LogParameterIsNaN(errors, "DTotal");
+            }
+            if (double.IsNaN(DInBetweenAquiferlayer))
+            {
+                LogParameterIsNaN(errors, "DInBetweenAquiferlayer");
+            }
+            if (double.IsNaN(DBottomAquiferlayer))
+            {
+                LogParameterIsNaN(errors, "DBottomAquiferlayer");
+            }
+            if (double.IsNaN(PermeabilityInBetweenAquiferlayer))
+            {
+                LogParameterIsNaN(errors, "PermeabilityInBetweenAquiferlayer");
+            }
+            if (double.IsNaN(PermeabilityBottomAquiferlayer))
+            {
+                LogParameterIsNaN(errors, "PermeabilityBottomAquiferlayer");
+            }
+            if (double.IsNaN(HExit))
+            {
+                LogParameterIsNaN(errors, "HExit");
+            }
+            if (double.IsNaN(D70))
+            {
+                LogParameterIsNaN(errors, "D70");
+            }
+            if (double.IsNaN(WhitesConstant))
+            {
+                LogParameterIsNaN(errors, "WhitesConstant");
+            }
+            if (double.IsNaN(BeddingAngle))
+            {
+                LogParameterIsNaN(errors, "BeddingAngle");
+            }
+            if (double.IsNaN(WaterViscosity))
+            {
+                LogParameterIsNaN(errors, "WaterViscosity");
+            }
+            return errors;
+        }
+
+        private void LogParameterIsNaN(IList<string> list, string paramName)
+        {
+            var msg = string.Format(Resources.PipingCalculatorSellmeijerVNK_LogParameterIsNaN_NaNParameterError, paramName);
+            list.Add(msg);
+        }
     }
 }
Index: dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.resx
===================================================================
diff -u -r376 -r797
--- dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.resx	(.../Resources.resx)	(revision 376)
+++ dam failuremechanisms/damPiping/trunk/src/Deltares.DamPiping.SellmeijerVNKCalculator/Properties/Resources.resx	(.../Resources.resx)	(revision 797)
@@ -101,4 +101,13 @@
   <data name="PipingModel2Calculation_CalculateHeadDropPC2_Error_in_Piping_DLL" xml:space="preserve">
     <value>Error in Piping DLL</value>
   </data>
+  <data name="PipingCalculatorSellmeijerVNK_PerformValidate_HRiver_HExit_Zero" xml:space="preserve">
+    <value>HRiver - HExit may not be 0.</value>
+  </data>
+  <data name="PipingCalculatorSellmeijerVNK_PerformValidate_RcLessThan0" xml:space="preserve">
+    <value>Rc may not be less than 0.</value>
+  </data>
+  <data name="PipingCalculatorSellmeijerVNK_LogParameterIsNaN_NaNParameterError" xml:space="preserve">
+    <value>Parameter {0} is not a number (NaN).</value>
+  </data>
 </root>
\ No newline at end of file