Index: Riskeer/Storage/src/Riskeer.Storage.Core/Read/FailureMechanismEntityReadExtensions.cs
===================================================================
diff -u -r071a12cf216a4b371c3f900504d5922270962a33 -rc8a0e54fd2029ac1760758292510f5354ae399e7
--- Riskeer/Storage/src/Riskeer.Storage.Core/Read/FailureMechanismEntityReadExtensions.cs	(.../FailureMechanismEntityReadExtensions.cs)	(revision 071a12cf216a4b371c3f900504d5922270962a33)
+++ Riskeer/Storage/src/Riskeer.Storage.Core/Read/FailureMechanismEntityReadExtensions.cs	(.../FailureMechanismEntityReadExtensions.cs)	(revision c8a0e54fd2029ac1760758292510f5354ae399e7)
@@ -680,9 +680,7 @@
 
         private static void ReadWaveImpactAsphaltCoverGeneralInput(this FailureMechanismEntity entity, GeneralWaveImpactAsphaltCoverInput generalInput)
         {
-            GeneralWaveImpactAsphaltCoverInput generalWaveImpactAsphaltCoverInput = entity.WaveImpactAsphaltCoverFailureMechanismMetaEntities.Single().Read();
-            generalInput.DeltaL = generalWaveImpactAsphaltCoverInput.DeltaL;
-            generalInput.ApplyLengthEffectInSection = generalWaveImpactAsphaltCoverInput.ApplyLengthEffectInSection;
+            entity.WaveImpactAsphaltCoverFailureMechanismMetaEntities.Single().Read(generalInput);
         }
 
         #endregion
Index: Riskeer/Storage/src/Riskeer.Storage.Core/Read/WaveImpactAsphaltCover/WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensions.cs
===================================================================
diff -u -rff27539a67b19406483c3e267c7942ff316a4ad1 -rc8a0e54fd2029ac1760758292510f5354ae399e7
--- Riskeer/Storage/src/Riskeer.Storage.Core/Read/WaveImpactAsphaltCover/WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensions.cs	(.../WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensions.cs)	(revision ff27539a67b19406483c3e267c7942ff316a4ad1)
+++ Riskeer/Storage/src/Riskeer.Storage.Core/Read/WaveImpactAsphaltCover/WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensions.cs	(.../WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensions.cs)	(revision c8a0e54fd2029ac1760758292510f5354ae399e7)
@@ -36,22 +36,24 @@
         /// Read the <see cref="WaveImpactAsphaltCoverFailureMechanismMetaEntity"/> and use the information to
         /// construct a <see cref="GeneralWaveImpactAsphaltCoverInput"/>.
         /// </summary>
-        /// <param name="entity">The <see cref="WaveImpactAsphaltCoverFailureMechanismMetaEntity"/> to create
+        /// <param name="entity">The <see cref="WaveImpactAsphaltCoverFailureMechanismMetaEntity"/> to update
         /// <see cref="GeneralWaveImpactAsphaltCoverInput"/> for.</param>
-        /// <returns>A new <see cref="GeneralWaveImpactAsphaltCoverInput"/>.</returns>
-        /// <exception cref="ArgumentNullException">Thrown when <paramref name="entity"/> is <c>null</c>.</exception>
-        internal static GeneralWaveImpactAsphaltCoverInput Read(this WaveImpactAsphaltCoverFailureMechanismMetaEntity entity)
+        /// <param name="generalInput">The <see cref="GeneralWaveImpactAsphaltCoverInput"/> to update.</param>
+        /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
+        internal static void Read(this WaveImpactAsphaltCoverFailureMechanismMetaEntity entity, GeneralWaveImpactAsphaltCoverInput generalInput)
         {
             if (entity == null)
             {
                 throw new ArgumentNullException(nameof(entity));
             }
-
-            return new GeneralWaveImpactAsphaltCoverInput
+            
+            if (generalInput == null)
             {
-                DeltaL = (RoundedDouble) entity.DeltaL,
-                ApplyLengthEffectInSection = Convert.ToBoolean(entity.ApplyLengthEffectInSection)
-            };
+                throw new ArgumentNullException(nameof(generalInput));
+            }
+
+            generalInput.DeltaL = (RoundedDouble) entity.DeltaL;
+            generalInput.ApplyLengthEffectInSection = Convert.ToBoolean(entity.ApplyLengthEffectInSection);
         }
     }
 }
\ No newline at end of file
Index: Riskeer/Storage/test/Riskeer.Storage.Core.Test/Read/WaveImpactAsphaltCover/WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensionsTest.cs
===================================================================
diff -u -rff27539a67b19406483c3e267c7942ff316a4ad1 -rc8a0e54fd2029ac1760758292510f5354ae399e7
--- Riskeer/Storage/test/Riskeer.Storage.Core.Test/Read/WaveImpactAsphaltCover/WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensionsTest.cs	(.../WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensionsTest.cs)	(revision ff27539a67b19406483c3e267c7942ff316a4ad1)
+++ Riskeer/Storage/test/Riskeer.Storage.Core.Test/Read/WaveImpactAsphaltCover/WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensionsTest.cs	(.../WaveImpactAsphaltCoverFailureMechanismMetaEntityReadExtensionsTest.cs)	(revision c8a0e54fd2029ac1760758292510f5354ae399e7)
@@ -36,26 +36,43 @@
         public void Read_EntityNull_ThrowsArgumentNullException()
         {
             // Call
-            TestDelegate test = () => ((WaveImpactAsphaltCoverFailureMechanismMetaEntity) null).Read();
+            void Call() => ((WaveImpactAsphaltCoverFailureMechanismMetaEntity) null)
+                .Read(new GeneralWaveImpactAsphaltCoverInput());
 
             // Assert
-            var exception = Assert.Throws<ArgumentNullException>(test);
+            var exception = Assert.Throws<ArgumentNullException>(Call);
             Assert.AreEqual("entity", exception.ParamName);
         }
+        
+        [Test]
+        public void Read_GeneralInputNull_ThrowsArgumentNullException()
+        {
+            // Setup
+            var entity = new WaveImpactAsphaltCoverFailureMechanismMetaEntity();
 
+            // Call
+            void Call() => entity.Read(null);
+
+            // Assert
+            var exception = Assert.Throws<ArgumentNullException>(Call);
+            Assert.AreEqual("generalInput", exception.ParamName);
+        }
+
         [Test]
-        public void Read_Always_ReturnGeneralWaveImpactAsphaltCoverInput()
+        public void Read_WithAllData_SetsGeneralInputProperties()
         {
             // Setup
             var random = new Random();
             var entity = new WaveImpactAsphaltCoverFailureMechanismMetaEntity
             {
-                DeltaL = random.NextRoundedDouble(1.0, 2000.0),
+                DeltaL = random.NextDouble(1, 2000),
                 ApplyLengthEffectInSection = Convert.ToByte(random.NextBoolean())
             };
 
+            var generalInput = new GeneralWaveImpactAsphaltCoverInput();
+
             // Call
-            GeneralWaveImpactAsphaltCoverInput generalInput = entity.Read();
+            entity.Read(generalInput);
 
             // Assert
             Assert.AreEqual(entity.DeltaL, generalInput.DeltaL, generalInput.DeltaL.GetAccuracy());