Which of the following describes a single-tiered system?

• A. One agency responding with a fire apparatus staffed with firefighter/paramedics
• B. Two agencies with separate apparatus
• C. Three agencies sharing command
• D. Only EMS responds without fire apparatus

Answer: (A)

A single-tier system means one organization provides the full response with a single unit that handles both fire suppression and medical care, using crews trained for both roles. The described scenario fits this because one agency (the fire department) responds with a fire apparatus whose crew are firefighter/paramedics, able to treat medical patients on scene while also handling firefighting if needed, all under one command and unit.

The other setups involve more than one agency or a split mission. Two agencies with separate apparatus require coordination between organizations; three agencies sharing command adds even more multi-agency coordination; EMS-only response without a fire apparatus lacks a single unit delivering both fire and medical capabilities.