The document discusses the role and responsibilities of the Incident Safety Officer (ISO) at structure fires. It outlines that the ISO should monitor risk levels and operational effectiveness, ensure an effective PAR is conducted, define control zones, determine needs for additional assistance, and apply the ISO Action Model. This includes evaluating rescue profile, environmental reconnaissance considering principal hazards and physical surroundings, crew exposure, resources like time and personnel, and providing safety briefings. Unique considerations for structures like those with central hallways, strip malls, and high-rises are also covered.