Which factor primarily affects the choice of fire suppression agent?

Choosing a fire suppression agent is influenced significantly by the type of building materials present. Different materials ignite and burn in distinct ways, which necessitates the use of specific agents to effectively control or extinguish fires. For instance, some materials may release toxic fumes when burned, requiring agents that not only extinguish flames but also minimize smoke and fumes. Overall, a proper understanding of the building's materials ensures that the selected suppression method is both effective and safe, ultimately guiding the choice of appropriate agents such as water, foam, or chemical suppressants based on those combustibility characteristics.

While the age of the fire suppression system, the expected size of the fire, and the number of occupants are relevant considerations in fire management, they do not directly influence the core decision regarding which suppression agent to use. The characteristics of building materials are paramount in determining how a fire will behave and subsequently dictate the most suitable suppressive measures.