Index: Ringtoets/GrassCoverErosionInwards/test/Ringtoets.GrassCoverErosionInwards.Forms.Test/Views/GrassCoverErosionInwardsFailureMechanismSectionResultRowTest.cs
===================================================================
diff -u -rf5a2d607a5b8053b232c1f3ad572a0acba6a4e3a -rbd3056331b8727d6f9758d1f4e5979694d439398
--- Ringtoets/GrassCoverErosionInwards/test/Ringtoets.GrassCoverErosionInwards.Forms.Test/Views/GrassCoverErosionInwardsFailureMechanismSectionResultRowTest.cs	(.../GrassCoverErosionInwardsFailureMechanismSectionResultRowTest.cs)	(revision f5a2d607a5b8053b232c1f3ad572a0acba6a4e3a)
+++ Ringtoets/GrassCoverErosionInwards/test/Ringtoets.GrassCoverErosionInwards.Forms.Test/Views/GrassCoverErosionInwardsFailureMechanismSectionResultRowTest.cs	(.../GrassCoverErosionInwardsFailureMechanismSectionResultRowTest.cs)	(revision bd3056331b8727d6f9758d1f4e5979694d439398)
@@ -24,6 +24,9 @@
 using Core.Common.Base.Data;
 using Core.Common.Base.Geometry;
 using NUnit.Framework;
+
+using Rhino.Mocks;
+
 using Ringtoets.Common.Data.FailureMechanism;
 using Ringtoets.Common.Data.TestUtil;
 using Ringtoets.GrassCoverErosionInwards.Data;
@@ -68,23 +71,24 @@
         public void AssessmentLayerOne_AlwaysOnChange_NotifyObserversOfResultAndResultPropertyChanged(bool newValue)
         {
             // Setup
+            var mocks = new MockRepository();
+            var observer = mocks.StrictMock<IObserver>();
+            observer.Expect(o => o.UpdateObserver());
+            mocks.ReplayAll();
+
             var section = CreateSection();
             var result = new GrassCoverErosionInwardsFailureMechanismSectionResult(section);
+            result.Attach(observer);
+
             var row = new GrassCoverErosionInwardsFailureMechanismSectionResultRow(result);
 
-            int counter = 0;
-            using (new Observer(() => counter++)
-            {
-                Observable = result
-            })
-            {
-                // Call
-                row.AssessmentLayerOne = newValue;
+            // Call
+            row.AssessmentLayerOne = newValue;
 
-                // Assert
-                Assert.AreEqual(1, counter);
-                Assert.AreEqual(newValue, result.AssessmentLayerOne);
-            }
+            // Assert
+            Assert.AreEqual(newValue, result.AssessmentLayerOne);
+            
+            mocks.VerifyAll();
         }
 
         [Test]