Which of the following is NOT a type of cabin fire?

A structural fire is not classified as a type of cabin fire because it typically refers to fires that originate in the framework or structure of a building, which is not applicable in the context of an aircraft cabin. Cabin fires are specifically related to incidents within the confines of the passenger area, which is designed and equipped to manage such emergencies.

Cabin fires can include galley fires, which may start due to cooking equipment, lavatory waste fires from improperly disposed items, and portable electronic device fires, often related to batteries or chargers. Each of these types of fires directly impacts the safety and procedures in an aircraft's cabin environment, while structural fires relate more to the broader safety considerations of the aircraft as a whole.