In recent decades there has been a change in perspective towards risk assessment in cultural and environmental heritage. Despite the positive impact of heritage on various aspects of society, it is often neglected in disaster risk management, mostly due to lack of strategies in sharing common methodologies and process knowledge. The SIRIUS project, centered in Ravenna (Italy), aims to localize global disaster management guidelines applied to cultural and environmental heritage. In the context of SIRIUS, a pattern-based OWL 2 DL ontology called the Heritage Risk Assessment Ontology (HeRO) is being developed to standardize risk assessment procedures and manage complex heritage risk data. In this contribution, its effectiveness is demonstrated through an in-depth exposition of its modules and an example scenario, promising practical application in an upcoming web-based tool. Future work involves semantic expansion, alignment with other heritage risk assessment methodologies, and further testing.