Upon arrival on the scene, how should the incident commander perform a proper size-up?

• A. By viewing from a distance outside only
• B. By walking or driving around all four sides
• C. By entering immediately
• D. By following instructions from bystanders

Answer: (B)

Start with a complete exterior assessment. On arrival, the incident commander should perform a thorough 360-degree size-up by walking or driving around all four sides of the structure. This exterior scan gathers essential clues about where the fire is located, what’s exposed to the fire, and what hazards may be present, such as compromised walls, smoke conditions, access points, and potential escape routes for crews. It also helps establish the initial incident action plan—deciding where to stage, what resources are needed, and where interior operations might safely begin.

This approach is the best because it provides a full picture of conditions from multiple angles, reducing the risk of missing critical information that could affect safety or effectiveness. It helps identify potential entry points, the presence of occupants, possible backdraft or flashover signs, and structural concerns before anyone goes inside, and it guides a safer, more informed interior strategy.

Viewing from a distance or entering immediately without this survey would risk missing crucial interior factors; relying on bystander instructions is unreliable for making safely grounded decisions.