What is the base resource mix for 4th and 5th Alarm Structure Fire?

• A. 1 Aerial, 3 Engines, 2 Medics, 2 Battalions
• B. 1 Aerial, 3 Engines, 1 Medic, 1 Battalion
• C. 2 Aerials, 3 Engines, 1 Medic, 1 Battalion
• D. 1 Aerial, 3 Engines, 1 Medic, 1 Battalion

Answer: (D)

Base resource mix for a 4th or 5th alarm structure fire is about balancing access, suppression, medical support, and command without overcommitting resources. One aerial provides necessary vertical access and ventilation for upper floors. Three engine companies supply the water, hose lines, and backup lines needed to knock down the fire and protect exposures. A single medic unit handles on-scene medical care for occupants and can assist responders if needed. One battalion chief directs operations, maintaining command and coordination across units. This combination covers the core needs efficiently; extra aerials, additional medics, or an extra battalion would be added only if the incident escalates or specific conditions demand more resources. Therefore, the base mix is one aerial, three engines, one medic, and one battalion.