Index: Ringtoets/StabilityPointStructures/test/Ringtoets.StabilityPointStructures.Data.Test/StabilityPointStructuresFailureMechanismSectionResultTest.cs
===================================================================
diff -u -r3127db01c67e5b95c17a3acb25705e42acdb4c50 -re5e23e07a418655a45382dd5cc01d537fc17dfa4
--- Ringtoets/StabilityPointStructures/test/Ringtoets.StabilityPointStructures.Data.Test/StabilityPointStructuresFailureMechanismSectionResultTest.cs	(.../StabilityPointStructuresFailureMechanismSectionResultTest.cs)	(revision 3127db01c67e5b95c17a3acb25705e42acdb4c50)
+++ Ringtoets/StabilityPointStructures/test/Ringtoets.StabilityPointStructures.Data.Test/StabilityPointStructuresFailureMechanismSectionResultTest.cs	(.../StabilityPointStructuresFailureMechanismSectionResultTest.cs)	(revision e5e23e07a418655a45382dd5cc01d537fc17dfa4)
@@ -48,6 +48,8 @@
             Assert.AreEqual(TailorMadeAssessmentProbabilityCalculationResultType.None, sectionResult.TailorMadeAssessmentResult);
             Assert.IsNaN(sectionResult.TailorMadeAssessmentProbability);
             Assert.AreSame(section, sectionResult.Section);
+            Assert.IsFalse(sectionResult.UseManualAssemblyProbability);
+            Assert.IsNaN(sectionResult.ManualAssemblyProbability);
         }
 
         [Test]
@@ -87,5 +89,46 @@
             // Assert
             Assert.AreEqual(validValue, sectionResult.TailorMadeAssessmentProbability);
         }
+
+        [Test]
+        [SetCulture("nl-NL")]
+        [TestCase(-20)]
+        [TestCase(-1e-6)]
+        [TestCase(1 + 1e-6)]
+        [TestCase(12)]
+        public void ManualAssemblyProbability_InvalidValue_ThrowsArgumentOutOfRangeException(double newValue)
+        {
+            // Setup
+            FailureMechanismSection section = FailureMechanismSectionTestFactory.CreateFailureMechanismSection();
+            var result = new StabilityPointStructuresFailureMechanismSectionResult(section);
+
+            // Call
+            TestDelegate test = () => result.ManualAssemblyProbability = newValue;
+
+            // Assert
+            string message = Assert.Throws<ArgumentOutOfRangeException>(test).Message;
+            const string expectedMessage = "De waarde voor de faalkans moet in het bereik [0,0, 1,0] liggen.";
+            Assert.AreEqual(expectedMessage, message);
+        }
+
+        [Test]
+        [TestCase(0)]
+        [TestCase(1e-6)]
+        [TestCase(0.5)]
+        [TestCase(1 - 1e-6)]
+        [TestCase(1)]
+        [TestCase(double.NaN)]
+        public void ManualAssemblyProbability_ValidValue_NewValueSet(double newValue)
+        {
+            // Setup
+            FailureMechanismSection section = FailureMechanismSectionTestFactory.CreateFailureMechanismSection();
+            var result = new StabilityPointStructuresFailureMechanismSectionResult(section);
+
+            // Call
+            result.ManualAssemblyProbability = newValue;
+
+            // Assert
+            Assert.AreEqual(newValue, result.ManualAssemblyProbability);
+        }
     }
 }
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