What key factor differentiates moderate/high risk structures from standard structures?

The key factor that differentiates moderate to high-risk structures from standard structures lies in occupancy and accessibility. In the context of fire tactics, moderate and high-risk structures are often characterized by certain types of occupancy that may present higher hazards, such as buildings occupied by vulnerable populations (e.g., schools, nursing homes) or those with specialized operations (e.g., chemical plants, high-rise buildings).

Accessibility is another critical aspect; these structures may be located in areas that pose challenges for emergency responders, whether due to traffic patterns, building configurations, or geographic constraints. The combination of the nature of the occupancy and how accessible the building is for firefighting operations significantly impacts firefighting strategy and resource allocation.

Other factors, such as the type of construction material used, the date of construction, and the number of occupants, while relevant in assessing fire risk and response tactics, do not encapsulate the comprehensive assessment that occupancy and accessibility provide regarding how a building might behave during a fire incident. Therefore, it is the unique interplay of occupancy type and ease of access that makes these structures fall into the moderate or high-risk category, warranting a different approach to fire response compared to standard structures.