diff --git a/osm_lcm/tests/test_ns_workflows.py b/osm_lcm/tests/test_ns_workflows.py
index a460b5e..082b155 100644
--- a/osm_lcm/tests/test_ns_workflows.py
+++ b/osm_lcm/tests/test_ns_workflows.py
@@ -126,18 +126,21 @@
                     task_queue=LCM_TASK_QUEUE,
                 )
 
-        assert [
-            call.kwargs["workflow"] == WORKFLOW_VNF_INSTANTIATE
-            and call.kwargs["arg"].vnfr_uuid
-            for call in mock_execute_child_workflow.call_args_list
-        ] == vnfr_ids
+        self.assertEqual(
+            [
+                call.kwargs["workflow"] == WORKFLOW_VNF_INSTANTIATE
+                and call.kwargs["arg"].vnfr_uuid
+                for call in mock_execute_child_workflow.call_args_list
+            ],
+            vnfr_ids,
+        )
 
-        assert_lcm_op_states(
+        self.assert_lcm_op_states(
             self.mock_update_lcm_operation_state_tracker.call_args_list,
             [LcmOperationState.PROCESSING, LcmOperationState.COMPLETED],
         )
 
-        assert_ns_states(
+        self.assert_ns_states(
             self.mock_update_ns_state_tracker.call_args_list, [NsState.INSTANTIATED]
         )
 
@@ -155,16 +158,16 @@
                 ],
                 debug_mode=True,
             ):
-                # TODO: Check this WorkflowFailureError is caused by a TestException
-                with self.assertRaises(WorkflowFailureError):
+                with self.assertRaises(WorkflowFailureError) as e_info:
                     await env.client.execute_workflow(
                         NsInstantiateWorkflow,
                         arg=self.input,
                         id=self.input.nslcmop["nsInstanceId"],
                         task_queue=LCM_TASK_QUEUE,
                     )
+                self.assertEqual(e_info.exception.cause.cause.type, "TestException")
 
-        assert_lcm_op_states(
+        self.assert_lcm_op_states(
             self.mock_update_lcm_operation_state_tracker.call_args_list,
             [LcmOperationState.PROCESSING, LcmOperationState.FAILED],
         )
@@ -183,24 +186,26 @@
                 ],
                 debug_mode=True,
             ):
-                # TODO: Check this WorkflowFailureError is caused by a TestException
-                with self.assertRaises(WorkflowFailureError):
+                with self.assertRaises(WorkflowFailureError) as e_info:
                     await env.client.execute_workflow(
                         NsInstantiateWorkflow,
                         arg=self.input,
                         id=self.input.nslcmop["nsInstanceId"],
                         task_queue=LCM_TASK_QUEUE,
                     )
-        assert_ns_states(
+                self.assertEqual(e_info.exception.cause.cause.type, "TestException")
+        self.assert_ns_states(
             self.mock_update_ns_state_tracker.call_args_list, [NsState.INSTANTIATED]
         )
 
+    def assert_ns_states(self, call_args_list, expected_states):
+        """Asserts that the NS state was set to each of the expected states (in order)."""
+        self.assertEqual(
+            [call.args[0].state for call in call_args_list], expected_states
+        )
 
-def assert_ns_states(call_args_list, expected_states):
-    """Asserts that the NS state was set to each of the expected states (in order)."""
-    assert [call.args[0].state for call in call_args_list] == expected_states
-
-
-def assert_lcm_op_states(call_args_list, expected_states):
-    """Asserts that the LCM operation was set to each of the exepcted states (in order)."""
-    assert [call.args[0].op_state for call in call_args_list] == expected_states
+    def assert_lcm_op_states(self, call_args_list, expected_states):
+        """Asserts that the LCM operation was set to each of the exepcted states (in order)."""
+        self.assertEqual(
+            [call.args[0].op_state for call in call_args_list], expected_states
+        )