"The SeverityLevels Ontology is a modelling of the syslog message severity values from RFC 5424. (...) This is used in conjunction with the SPIN vocabulary to label exceptions that we may create in our build process. This process makes extensive use of SPIN rules. Validation tests are applied to a given data model via a SPARQL construct query and any exceptions raised are added to the :Graph object associated to a class. This :Graph object is used to add RDF annotations about the class instance named graph."