If there is no officer on the first-arriving unit, who assumes command?

• A. No one, until an officer arrives
• B. The person those present select
• C. The firefighter with the highest seniority
• D. Whomever the nearest responding chief officer designates over the radio

Answer: (C)

Command must be established immediately on arrival when no officer is present. In that moment, the firefighter with the highest seniority on scene steps into command because they are the most experienced there and can quickly set up incident command, establish priorities, and organize initial actions. This provides immediate leadership, clarity of direction, and a single point of authority for coordinating resources and safety. As soon as a higher-ranking officer arrives, they can assume command from the interim without losing continuity. Waiting for an officer to arrive, letting the group choose someone, or waiting for radio designation would all create delays and potential confusion on the scene.