Index: Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismSectionResultTest.cs
===================================================================
diff -u -r81fa8a9bf3bd503cbd280e88b8f6037a840cff12 -rb6e0f8d41d92ed18c902138dd49cce6e703ee883
--- Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismSectionResultTest.cs	(.../PipingFailureMechanismSectionResultTest.cs)	(revision 81fa8a9bf3bd503cbd280e88b8f6037a840cff12)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismSectionResultTest.cs	(.../PipingFailureMechanismSectionResultTest.cs)	(revision b6e0f8d41d92ed18c902138dd49cce6e703ee883)
@@ -19,9 +19,13 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System;
+using Core.Common.Base.Data;
 using Core.Common.Base.Geometry;
+using Core.Common.TestUtil;
 using NUnit.Framework;
 using Ringtoets.Common.Data.FailureMechanism;
+using Ringtoets.Common.Data.TestUtil;
 
 namespace Ringtoets.Piping.Data.Test
 {
@@ -32,18 +36,61 @@
         public void Constructor_WithParameters_ExpectedValues()
         {
             // Setup
-            var section = new FailureMechanismSection("test", new[]
-            {
-                new Point2D(0, 0)
-            });
+            FailureMechanismSection section = CreateSection();
 
             // Call
             var sectionResult = new PipingFailureMechanismSectionResult(section);
 
             // Assert
             Assert.IsInstanceOf<FailureMechanismSectionResult>(sectionResult);
             Assert.AreSame(section, sectionResult.Section);
+            Assert.IsNaN(sectionResult.AssessmentLayerThree);
             Assert.IsNaN(sectionResult.GetAssessmentLayerTwoA(new PipingCalculationScenario[0]));
         }
+
+        [Test]
+        [TestCase(double.NegativeInfinity)]
+        [TestCase(double.PositiveInfinity)]
+        [TestCase(1.1)]
+        [TestCase(-0.1)]
+        public void AssessmentLayerThree_SetInvalidValue_ThrowsArgumentOutOfRangeException(double invalidValue)
+        {
+            // Setup
+            var sectionResult = new PipingFailureMechanismSectionResult(CreateSection());
+
+            // Call
+            TestDelegate call = () => sectionResult.AssessmentLayerThree = (RoundedDouble) invalidValue;
+
+            // Assert
+            const string expectedMessage = "Kans moet in het bereik [0.0, 1.0] liggen.";
+            TestHelper.AssertThrowsArgumentExceptionAndTestMessage<ArgumentOutOfRangeException>(call,
+                                                                                                expectedMessage);
+        }
+
+        [Test]
+        [TestCase(double.NaN)]
+        [TestCase(0)]
+        [TestCase(1)]
+        [TestCase(0.5)]
+        public void AssessmentLayerThree_SetValidValue_SetsValue(double validValue)
+        {
+            // Setup
+            var sectionResult = new PipingFailureMechanismSectionResult(CreateSection());
+
+            // Call
+            TestDelegate call = () => sectionResult.AssessmentLayerThree = (RoundedDouble) validValue;
+
+            // Assert
+            Assert.DoesNotThrow(call);
+            Assert.AreEqual(validValue, sectionResult.AssessmentLayerThree, sectionResult.AssessmentLayerThree.GetAccuracy());
+        }
+
+        private static FailureMechanismSection CreateSection()
+        {
+            return new FailureMechanismSection("test", new[]
+            {
+                new Point2D(0, 0)
+            });
+        }
     }
 }
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