diff --git a/src/fesa/assembly/load_assembler.cpp b/src/fesa/assembly/load_assembler.cpp
index 695e911..3f0bb83 100644
--- a/src/fesa/assembly/load_assembler.cpp
+++ b/src/fesa/assembly/load_assembler.cpp
@@ -17,6 +17,7 @@ namespace fesa {
 namespace {
 
 constexpr std::size_t dofsPerNode = 6U;
+constexpr double shellMomentProjectionTolerance = 1.0e-12;
 
 Status loadFailure(
     const std::string& code,
@@ -215,6 +216,70 @@ Status validateFiniteVector(
     return Status::ok();
 }
 
+Status validateShellMoments(
+    const Domain& domain,
+    const Vector& fullLoad) {
+    if (domain.shellElements().empty()) {
+        return Status::ok();
+    }
+
+    std::vector<const ShellNodeInitialFrame*> frameByNode(
+        domain.nodes().size(), nullptr);
+    for (const auto& frame : domain.shellNodeInitialFrames()) {
+        if (frame.nodeIndex >= frameByNode.size() ||
+            frameByNode[frame.nodeIndex] != nullptr) {
+            return loadFailure(
+                "invalid-shell-director",
+                {domain.sourcePath(), 0U},
+                "NODE",
+                std::to_string(frame.nodeIndex),
+                "Shell nodal directors must have unique in-range node identities.");
+        }
+        frameByNode[frame.nodeIndex] = &frame;
+    }
+
+    for (std::size_t node = 0U; node < domain.nodes().size(); ++node) {
+        const double momentX = fullLoad[node * dofsPerNode + 3U];
+        const double momentY = fullLoad[node * dofsPerNode + 4U];
+        const double momentZ = fullLoad[node * dofsPerNode + 5U];
+        if (momentX == 0.0 && momentY == 0.0 && momentZ == 0.0) {
+            continue;
+        }
+
+        const auto* const frame = frameByNode[node];
+        if (frame == nullptr) {
+            return loadFailure(
+                "invalid-shell-director",
+                domain.nodes()[node].location,
+                "NODE",
+                domain.nodes()[node].sourceId.sourceLabelText,
+                "A loaded shell node must have an approved initial director.");
+        }
+
+        const double momentScale = std::max(
+            std::abs(momentX),
+            std::max(std::abs(momentY), std::abs(momentZ)));
+        const double scaledX = momentX / momentScale;
+        const double scaledY = momentY / momentScale;
+        const double scaledZ = momentZ / momentScale;
+        const double scaledNorm = std::hypot(scaledX, scaledY, scaledZ);
+        const double scaledDot =
+            frame->director[0U] * scaledX +
+            frame->director[1U] * scaledY +
+            frame->director[2U] * scaledZ;
+        const double projectionRatio = std::abs(scaledDot) / scaledNorm;
+        if (!(projectionRatio <= shellMomentProjectionTolerance)) {
+            return loadFailure(
+                "unsupported-drilling-load",
+                domain.nodes()[node].location,
+                "CLOAD",
+                domain.nodes()[node].sourceId.sourceLabelText,
+                "The aggregate nodal moment has an unsupported director-parallel component.");
+        }
+    }
+    return Status::ok();
+}
+
 } // namespace
 
 Result<Vector> LoadAssembler::assembleFullNodalLoad(
@@ -328,6 +393,10 @@ Result<Vector> LoadAssembler::assembleFullNodalLoad(
             fullLoad[fullDof] = accumulated;
         }
     }
+    const Status shellMomentStatus = validateShellMoments(domain, fullLoad);
+    if (!shellMomentStatus.isOk()) {
+        return Result<Vector>::failure(shellMomentStatus);
+    }
     return Result<Vector>::success(std::move(fullLoad));
 }
 
diff --git a/tests/unit/assembly/load_assembler_test.cpp b/tests/unit/assembly/load_assembler_test.cpp
index 241d702..be87014 100644
--- a/tests/unit/assembly/load_assembler_test.cpp
+++ b/tests/unit/assembly/load_assembler_test.cpp
@@ -76,6 +76,69 @@ LoadFixture makeFixture(
     return {std::move(domain), std::move(model), std::move(dofs)};
 }
 
+LoadFixture makeShellFixture(
+    std::vector<fesa::BoundaryCondition> boundaries,
+    std::vector<fesa::NodalLoad> loads) {
+    const std::filesystem::path source{"models/shell-load-assembly.inp"};
+    fesa::ModelDefinition definition{};
+    definition.sourcePath = source;
+    definition.sourceContentIdentity = "fnv1a64:1122334455667788";
+    definition.nodes = {
+        {{"Shell-1", 10, "10"}, {0.0, 0.0, 0.0}, {source, 2U}},
+        {{"Shell-1", 20, "20"}, {1.0, 0.0, 0.0}, {source, 3U}},
+        {{"Shell-1", 30, "30"}, {1.0, 1.0, 0.0}, {source, 4U}},
+        {{"Shell-1", 40, "40"}, {0.0, 1.0, 0.0}, {source, 5U}}};
+    definition.materials = {
+        {"Material", 1000.0, 0.25, {source, 6U}}};
+    definition.shellSections = {
+        {"ShellSection", 0.1, 0U, {source, 7U}}};
+    definition.shellElements = {{
+        {"Shell-1", 1, "1"},
+        fesa::ShellSourceElementType::s4,
+        {0U, 1U, 2U, 3U},
+        0U,
+        0U,
+        {source, 8U}}};
+    for (std::size_t node = 0U; node < definition.nodes.size(); ++node) {
+        definition.shellNodeInitialFrames.push_back({
+            static_cast<fesa::EntityIndex>(node),
+            {0.0, 0.0, 1.0},
+            {1.0, 0.0, 0.0},
+            {0.0, 1.0, 0.0}});
+    }
+    definition.steps = {{
+        "Step-1",
+        std::move(boundaries),
+        std::move(loads),
+        0.1,
+        1.0,
+        0.01,
+        1.0,
+        {source, 20U}}};
+
+    auto domainResult = fesa::Domain::create(std::move(definition));
+    if (!domainResult.hasValue()) {
+        throw std::runtime_error{"Shell load fixture Domain construction failed."};
+    }
+    auto domain = std::make_unique<fesa::Domain>(
+        std::move(domainResult.value()));
+
+    auto modelResult = fesa::AnalysisModel::create(*domain);
+    if (!modelResult.hasValue()) {
+        throw std::runtime_error{"Shell load fixture AnalysisModel construction failed."};
+    }
+    auto model = std::make_unique<fesa::AnalysisModel>(
+        std::move(modelResult.value()));
+
+    auto dofResult = fesa::DofManager::create(*model);
+    if (!dofResult.hasValue()) {
+        throw std::runtime_error{"Shell load fixture DofManager construction failed."};
+    }
+    auto dofs = std::make_unique<fesa::DofManager>(
+        std::move(dofResult.value()));
+    return {std::move(domain), std::move(model), std::move(dofs)};
+}
+
 fesa::SparseMatrix makeDenseSparse(
     const std::size_t rows,
     const std::size_t columns,
@@ -174,6 +237,100 @@ TEST(LoadAssembly, AccumulatesSignedLoadsInSourceOrder) {
     EXPECT_DOUBLE_EQ(second.value()[0U], 0.0);
 }
 
+// MITC4-LOAD-001
+TEST(LoadAssembly, AggregatesAllSixGlobalShellLoadComponentsInSourceOrder) {
+    const std::filesystem::path source{"models/shell-load-assembly.inp"};
+    auto fixture = makeShellFixture(
+        {},
+        {{"10", 1, 1.0e16, {source, 30U}},
+         {"10", 1, -1.0e16, {source, 31U}},
+         {"10", 1, 1.0, {source, 32U}},
+         {"10", 2, 2.0, {source, 33U}},
+         {"10", 3, 3.0, {source, 34U}},
+         {"10", 4, 1.0e16, {source, 35U}},
+         {"10", 4, -1.0e16, {source, 36U}},
+         {"10", 4, 4.0, {source, 37U}},
+         {"10", 5, 5.0, {source, 38U}},
+         {"10", 6, 6.0, {source, 39U}},
+         {"10", 6, -6.0, {source, 40U}}});
+
+    const auto result = fesa::LoadAssembler::assembleFullNodalLoad(
+        *fixture.model, *fixture.dofs);
+
+    ASSERT_TRUE(result.hasValue());
+    ASSERT_EQ(result.value().size(), 24U);
+    EXPECT_EQ(
+        std::vector<double>(result.value().data(), result.value().data() + 6U),
+        (std::vector<double>{1.0, 2.0, 3.0, 4.0, 5.0, 0.0}));
+}
+
+// MITC4-LOAD-002
+TEST(LoadAssembly, AcceptsExactlyZeroAggregateShellMoment) {
+    const std::filesystem::path source{"models/shell-load-assembly.inp"};
+    auto fixture = makeShellFixture(
+        {},
+        {{"10", 4, 3.0, {source, 30U}},
+         {"10", 4, -3.0, {source, 31U}},
+         {"10", 5, 4.0, {source, 32U}},
+         {"10", 5, -4.0, {source, 33U}},
+         {"10", 6, 5.0, {source, 34U}},
+         {"10", 6, -5.0, {source, 35U}}});
+
+    const auto result = fesa::LoadAssembler::assembleFullNodalLoad(
+        *fixture.model, *fixture.dofs);
+
+    ASSERT_TRUE(result.hasValue());
+    EXPECT_DOUBLE_EQ(result.value()[3U], 0.0);
+    EXPECT_DOUBLE_EQ(result.value()[4U], 0.0);
+    EXPECT_DOUBLE_EQ(result.value()[5U], 0.0);
+}
+
+// MITC4-LOAD-003
+TEST(LoadAssembly, EnforcesAggregateShellMomentDirectorProjectionThreshold) {
+    const std::filesystem::path source{"models/shell-load-assembly.inp"};
+    auto acceptedFixture = makeShellFixture(
+        {},
+        {{"10", 4, 1.0, {source, 30U}},
+         {"10", 6, 1.0e-12, {source, 31U}}});
+    auto rejectedFixture = makeShellFixture(
+        {},
+        {{"10", 4, 1.0, {source, 30U}},
+         {"10", 6, 2.0e-12, {source, 31U}}});
+
+    const auto accepted = fesa::LoadAssembler::assembleFullNodalLoad(
+        *acceptedFixture.model, *acceptedFixture.dofs);
+    const auto rejected = fesa::LoadAssembler::assembleFullNodalLoad(
+        *rejectedFixture.model, *rejectedFixture.dofs);
+
+    ASSERT_TRUE(accepted.hasValue());
+    ASSERT_FALSE(rejected.hasValue());
+    EXPECT_EQ(rejected.status().failureCategory(), fesa::FailureCategory::model);
+    ASSERT_EQ(rejected.status().diagnostics().size(), 1U);
+    EXPECT_EQ(
+        rejected.status().diagnostics()[0U].code,
+        "unsupported-drilling-load");
+    EXPECT_EQ(rejected.status().diagnostics()[0U].keyword, "CLOAD");
+    EXPECT_EQ(rejected.status().diagnostics()[0U].entityIdentity, "10");
+}
+
+// MITC4-LOAD-004
+TEST(LoadAssembly, RejectsDrillingMomentBeforeEffectiveRhsCanBeFormed) {
+    const std::filesystem::path source{"models/shell-load-assembly.inp"};
+    auto fixture = makeShellFixture(
+        {{"10", 1, 1, 2.0, {source, 21U}}},
+        {{"10", 6, 1.0, {source, 30U}}});
+
+    const auto rejected = fesa::LoadAssembler::assembleFullNodalLoad(
+        *fixture.model, *fixture.dofs);
+
+    ASSERT_FALSE(rejected.hasValue());
+    EXPECT_EQ(rejected.status().failureCategory(), fesa::FailureCategory::model);
+    ASSERT_EQ(rejected.status().diagnostics().size(), 1U);
+    EXPECT_EQ(
+        rejected.status().diagnostics()[0U].code,
+        "unsupported-drilling-load");
+}
+
 TEST(LoadAssembly, FormsNonzeroPrescribedEffectiveRhs) {
     const std::filesystem::path source{"models/load-assembly.inp"};
     auto fixture = makeFixture(