Index: Ringtoets/Integration/src/Ringtoets.Integration.Data/StandAlone/AssemblyFactories/MicrostabilityFailureMechanismAssemblyFactory.cs
===================================================================
diff -u -r06800c4b5c53dd8a385a9f15ce44e9c4038a3726 -rc43f7692bfadc0b065baf71ef3dd382c32da8566
--- Ringtoets/Integration/src/Ringtoets.Integration.Data/StandAlone/AssemblyFactories/MicrostabilityFailureMechanismAssemblyFactory.cs	(.../MicrostabilityFailureMechanismAssemblyFactory.cs)	(revision 06800c4b5c53dd8a385a9f15ce44e9c4038a3726)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Data/StandAlone/AssemblyFactories/MicrostabilityFailureMechanismAssemblyFactory.cs	(.../MicrostabilityFailureMechanismAssemblyFactory.cs)	(revision c43f7692bfadc0b065baf71ef3dd382c32da8566)
@@ -172,6 +172,27 @@
         }
 
         /// <summary>
+        /// Gets the assembly category group of the given <paramref name="failureMechanismSectionResult"/>.
+        /// </summary>
+        /// <param name="failureMechanismSectionResult">The failure mechanism section result to get the assembly category group for.</param>
+        /// <returns>A <see cref="FailureMechanismSectionAssemblyCategoryGroup"/>.</returns>
+        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
+        /// <exception cref="AssemblyException">Thrown when the <see cref="FailureMechanismSectionAssembly"/>
+        /// could not be created.</exception>
+        public static FailureMechanismSectionAssemblyCategoryGroup GetSectionAssemblyCategoryGroup(
+            MicrostabilityFailureMechanismSectionResult failureMechanismSectionResult)
+        {
+            if (failureMechanismSectionResult == null)
+            {
+                throw new ArgumentNullException(nameof(failureMechanismSectionResult));
+            }
+
+            return failureMechanismSectionResult.UseManualAssemblyCategoryGroup
+                       ? failureMechanismSectionResult.ManualAssemblyCategoryGroup
+                       : AssembleCombinedAssessment(failureMechanismSectionResult);
+        }
+
+        /// <summary>
         /// Assembles the failure mechanism assembly.
         /// </summary>
         /// <param name="failureMechanism">The failure mechanism to assemble for.</param>
@@ -193,9 +214,7 @@
             }
 
             IEnumerable<FailureMechanismSectionAssemblyCategoryGroup> sectionAssemblies =
-                failureMechanism.SectionResults.Select(sectionResult => sectionResult.UseManualAssemblyCategoryGroup
-                                                                            ? sectionResult.ManualAssemblyCategoryGroup
-                                                                            : AssembleCombinedAssessment(sectionResult)).ToArray();
+                failureMechanism.SectionResults.Select(GetSectionAssemblyCategoryGroup).ToArray();
 
             IAssemblyToolCalculatorFactory calculatorFactory = AssemblyToolCalculatorFactory.Instance;
             IFailureMechanismAssemblyCalculator calculator =
Index: Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/StandAlone/AssemblyFactories/MicrostabilityFailureMechanismAssemblyFactoryTest.cs
===================================================================
diff -u -r5e0a72833803f6a51d6e70a166bdd48d1d4418c7 -rc43f7692bfadc0b065baf71ef3dd382c32da8566
--- Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/StandAlone/AssemblyFactories/MicrostabilityFailureMechanismAssemblyFactoryTest.cs	(.../MicrostabilityFailureMechanismAssemblyFactoryTest.cs)	(revision 5e0a72833803f6a51d6e70a166bdd48d1d4418c7)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/StandAlone/AssemblyFactories/MicrostabilityFailureMechanismAssemblyFactoryTest.cs	(.../MicrostabilityFailureMechanismAssemblyFactoryTest.cs)	(revision c43f7692bfadc0b065baf71ef3dd382c32da8566)
@@ -370,6 +370,112 @@
 
         #endregion
 
+        #region GetSectionAssemblyCategoryGroup
+
+        [Test]
+        public void GetSectionAssemblyCategoryGroup_FailureMechanismSectionResultNull_ThrowsArgumentNullException()
+        {
+            // Call
+            TestDelegate call = () => MicrostabilityFailureMechanismAssemblyFactory.GetSectionAssemblyCategoryGroup(
+                null);
+
+            // Assert
+            var exception = Assert.Throws<ArgumentNullException>(call);
+            Assert.AreEqual("failureMechanismSectionResult", exception.ParamName);
+        }
+
+        [Test]
+        public void GetSectionAssemblyCategoryGroup_WithoutManualInput_SetsInputOnCalculator()
+        {
+            // Setup
+            var sectionResult = new MicrostabilityFailureMechanismSectionResult(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+            
+            using (new AssemblyToolCalculatorFactoryConfig())
+            {
+                var calculatorFactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorFactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
+
+                // Call
+                MicrostabilityFailureMechanismAssemblyFactory.GetSectionAssemblyCategoryGroup(
+                    sectionResult);
+
+                // Assert
+                FailureMechanismSectionAssemblyCategoryGroup expectedSimpleAssembly = MicrostabilityFailureMechanismAssemblyFactory.AssembleSimpleAssessment(
+                    sectionResult);
+                FailureMechanismSectionAssemblyCategoryGroup expectedDetailedAssembly = MicrostabilityFailureMechanismAssemblyFactory.AssembleDetailedAssessment(
+                    sectionResult);
+                FailureMechanismSectionAssemblyCategoryGroup expectedTailorMadeAssembly = MicrostabilityFailureMechanismAssemblyFactory.AssembleTailorMadeAssessment(
+                    sectionResult);
+
+                Assert.AreEqual(expectedSimpleAssembly, calculator.CombinedSimpleAssemblyGroupInput);
+                Assert.AreEqual(expectedDetailedAssembly, calculator.CombinedDetailedAssemblyGroupInput);
+                Assert.AreEqual(expectedTailorMadeAssembly, calculator.CombinedTailorMadeAssemblyGroupInput);
+            }
+        }
+
+        [Test]
+        public void GetSectionAssemblyCategoryGroup_WithoutManualInput_ReturnsOutput()
+        {
+            // Setup
+            var sectionResult = new MicrostabilityFailureMechanismSectionResult(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+            
+            using (new AssemblyToolCalculatorFactoryConfig())
+            {
+                // Call
+                FailureMechanismSectionAssemblyCategoryGroup categoryGroup = MicrostabilityFailureMechanismAssemblyFactory.GetSectionAssemblyCategoryGroup(
+                    sectionResult);
+
+                // Assert
+                FailureMechanismSectionAssemblyCategoryGroup expectedAssembly = MicrostabilityFailureMechanismAssemblyFactory.AssembleCombinedAssessment(
+                    sectionResult);
+                Assert.AreEqual(categoryGroup, expectedAssembly);
+            }
+        }
+
+        [Test]
+        public void GetSectionAssemblyCategoryGroup_WithManualInput_ReturnsOutput()
+        {
+            // Setup
+            var sectionResult = new MicrostabilityFailureMechanismSectionResult(FailureMechanismSectionTestFactory.CreateFailureMechanismSection())
+            {
+                UseManualAssemblyCategoryGroup = true,
+                ManualAssemblyCategoryGroup = new Random(39).NextEnumValue<FailureMechanismSectionAssemblyCategoryGroup>()
+            };
+
+            // Call
+            FailureMechanismSectionAssemblyCategoryGroup categoryGroup = MicrostabilityFailureMechanismAssemblyFactory.GetSectionAssemblyCategoryGroup(
+                sectionResult);
+
+            // Assert
+            Assert.AreEqual(categoryGroup, sectionResult.ManualAssemblyCategoryGroup);
+        }
+
+        [Test]
+        public void GetSectionAssemblyCategoryGroup_WithoutManualInputAndCalculatorThrowsException_ThrowsAssemblyException()
+        {
+            // Setup
+            var sectionResult = new MicrostabilityFailureMechanismSectionResult(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+
+            using (new AssemblyToolCalculatorFactoryConfig())
+            {
+                var calculatorfactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorfactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
+                calculator.ThrowExceptionOnCalculateCombinedAssembly = true;
+
+                // Call
+                TestDelegate call = () => MicrostabilityFailureMechanismAssemblyFactory.GetSectionAssemblyCategoryGroup(
+                    sectionResult);
+
+                // Assert
+                var exception = Assert.Throws<AssemblyException>(call);
+                Exception innerException = exception.InnerException;
+                Assert.IsInstanceOf<FailureMechanismSectionAssemblyCalculatorException>(innerException);
+                Assert.AreEqual(innerException.Message, exception.Message);
+            }
+        }
+
+        #endregion
+
         #region Failure Mechanism Assembly
 
         [Test]