Index: Ringtoets/Common/src/Ringtoets.Common.Service/ProbabilityAssessmentService.cs
===================================================================
diff -u -r55c178c8718a4ddb95cf2a99afb9fbdb92915b43 -r573a8a37ccc0f7565a44bf50bba861cf0b181f1c
--- Ringtoets/Common/src/Ringtoets.Common.Service/ProbabilityAssessmentService.cs	(.../ProbabilityAssessmentService.cs)	(revision 55c178c8718a4ddb95cf2a99afb9fbdb92915b43)
+++ Ringtoets/Common/src/Ringtoets.Common.Service/ProbabilityAssessmentService.cs	(.../ProbabilityAssessmentService.cs)	(revision 573a8a37ccc0f7565a44bf50bba861cf0b181f1c)
@@ -19,7 +19,7 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
-using MathNet.Numerics.Distributions;
+using Core.Common.Utils;
 using Ringtoets.Common.Data.Probability;
 
 namespace Ringtoets.Common.Service
@@ -41,8 +41,8 @@
         public static ProbabilityAssessmentOutput Calculate(int returnPeriod, double contribution, double lengthEffectN, double reliability)
         {
             var requiredProbability = RequiredProbability(contribution/100.0, returnPeriod, lengthEffectN);
-            var probability = ReliabilityToProbability(reliability);
-            var requiredReliability = ProbabilityToReliability(requiredProbability);
+            var probability = StatisticsConverter.ReliabilityToProbability(reliability);
+            var requiredReliability = StatisticsConverter.ProbabilityToReliability(requiredProbability);
             var factorOfSafety = FactorOfSafety(reliability, requiredReliability);
 
             return new ProbabilityAssessmentOutput(requiredProbability,
@@ -57,16 +57,6 @@
             return contribution*(1.0/returnPeriod)/lengthEffectN;
         }
 
-        private static double ReliabilityToProbability(double reliability)
-        {
-            return Normal.CDF(0, 1, -reliability);
-        }
-
-        private static double ProbabilityToReliability(double probability)
-        {
-            return Normal.InvCDF(0, 1, 1 - probability);
-        }
-
         private static double FactorOfSafety(double reliability, double requiredReliability)
         {
             return reliability/requiredReliability;
Index: Ringtoets/Piping/src/Ringtoets.Piping.Service/PipingSemiProbabilisticCalculationService.cs
===================================================================
diff -u -r55c178c8718a4ddb95cf2a99afb9fbdb92915b43 -r573a8a37ccc0f7565a44bf50bba861cf0b181f1c
--- Ringtoets/Piping/src/Ringtoets.Piping.Service/PipingSemiProbabilisticCalculationService.cs	(.../PipingSemiProbabilisticCalculationService.cs)	(revision 55c178c8718a4ddb95cf2a99afb9fbdb92915b43)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Service/PipingSemiProbabilisticCalculationService.cs	(.../PipingSemiProbabilisticCalculationService.cs)	(revision 573a8a37ccc0f7565a44bf50bba861cf0b181f1c)
@@ -20,7 +20,7 @@
 // All rights reserved.
 
 using System;
-using MathNet.Numerics.Distributions;
+using Core.Common.Utils;
 using Ringtoets.Piping.Data;
 using Ringtoets.Piping.Service.Properties;
 
@@ -150,7 +150,7 @@
         private void CalculateRequiredReliability()
         {
             requiredProbability = RequiredProbability();
-            requiredReliability = ProbabilityToReliability(requiredProbability);
+            requiredReliability = StatisticsConverter.ProbabilityToReliability(requiredProbability);
         }
 
         /// <summary>
@@ -159,16 +159,16 @@
         private void CalculatePipingReliability()
         {
             upliftReliability = SubMechanismReliability(upliftFactorOfSafety, upliftFactors);
-            upliftProbability = ReliabilityToProbability(upliftReliability);
+            upliftProbability = StatisticsConverter.ReliabilityToProbability(upliftReliability);
 
             heaveReliability = SubMechanismReliability(heaveFactorOfSafety, heaveFactors);
-            heaveProbability = ReliabilityToProbability(heaveReliability);
+            heaveProbability = StatisticsConverter.ReliabilityToProbability(heaveReliability);
 
             sellmeijerReliability = SubMechanismReliability(sellmeijerFactorOfSafety, sellmeijerFactors);
-            sellmeijerProbability = ReliabilityToProbability(sellmeijerReliability);
+            sellmeijerProbability = StatisticsConverter.ReliabilityToProbability(sellmeijerReliability);
 
             pipingProbability = PipingProbability(upliftProbability, heaveProbability, sellmeijerProbability);
-            pipingReliability = ProbabilityToReliability(pipingProbability);
+            pipingReliability = StatisticsConverter.ProbabilityToReliability(pipingProbability);
         }
 
         /// <summary>
@@ -195,7 +195,7 @@
         private double SubMechanismReliability(double factorOfSafety, SubCalculationFactors factors)
         {
             var norm = (1.0/returnPeriod);
-            var bNorm = ProbabilityToReliability(norm);
+            var bNorm = StatisticsConverter.ProbabilityToReliability(norm);
 
             return (1/factors.A)*(Math.Log(factorOfSafety/factors.B) + (factors.C*bNorm));
         }
@@ -208,16 +208,6 @@
             }
         }
 
-        private static double ReliabilityToProbability(double reliability)
-        {
-            return Normal.CDF(0, 1, -reliability);
-        }
-
-        private static double ProbabilityToReliability(double probability)
-        {
-            return Normal.InvCDF(0, 1, 1 - probability);
-        }
-
         #region sub-calculation constants
 
         private struct SubCalculationFactors