Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Services/HydraRingCalculationService.cs
===================================================================
diff -u -r586ee3c66ed8191b42a3626a9a79fc35faffb6d4 -r5cdaf6a62202805aa0abe5636e372a66b1bec723
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Services/HydraRingCalculationService.cs	(.../HydraRingCalculationService.cs)	(revision 586ee3c66ed8191b42a3626a9a79fc35faffb6d4)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Services/HydraRingCalculationService.cs	(.../HydraRingCalculationService.cs)	(revision 5cdaf6a62202805aa0abe5636e372a66b1bec723)
@@ -34,12 +34,25 @@
     /// <summary>
     /// Service that provides methods for performing Hydra-Ring calculations.
     /// </summary>
-    public static class HydraRingCalculationService
+    public class HydraRingCalculationService : IHydraRingCalculationService
     {
         private static readonly ILog log = LogManager.GetLogger(typeof(HydraRingCalculationService));
 
         private static Process hydraRingProcess;
+        private static IHydraRingCalculationService instance;
 
+        public static IHydraRingCalculationService Instance
+        {
+            get
+            {
+                return instance ?? (instance = new HydraRingCalculationService());
+            }
+            set
+            {
+                instance = value;
+            }
+        }
+
         /// <summary>
         /// This method performs a type II calculation via Hydra-Ring:
         /// Iterate towards a target probability, provided as reliability index.
@@ -49,7 +62,7 @@
         /// <param name="uncertaintiesType">The <see cref="HydraRingUncertaintiesType"/> to use while executing the calculation.</param>
         /// <param name="hydraRingCalculationInput">The input of the calculation to perform.</param>
         /// <param name="parsers">Parsers that will be invoked after the Hydra-Ring calculation has ran.</param>
-        public static void PerformCalculation(
+        public void PerformCalculation(
             string hlcdDirectory,
             string ringId,
             HydraRingUncertaintiesType uncertaintiesType,