Fireground Size-Up

What Is Fireground Size-Up?

Fireground size-up is the continuous, systematic mental evaluation of incident facts, probabilities, and environmental conditions — starting at dispatch, expanding upon arrival with a 360-degree walk-around, and continuing throughout the call — used to formulate and adjust the Incident Action Plan (IAP).

Why Fireground Size-Up Matters on the Fireground

A flawed size-up leads to incorrect strategy selection, improper hose line sizing, and unmanaged collapse hazards. Thorough size-up ensures tactical objectives match building construction, fire location, and victim survival profiles.

Relevant NFPA Standards

• NFPA 1010: Standard on Professional Qualifications for Firefighters
• NFPA 1550: Standard for Emergency Responder Health and Safety

Field Procedures & Tactical Steps

1. Review dispatch information (occupancy type, caller reports, time of day) while en route.
2. Transmit initial arrival report: structure description, visible smoke/fire conditions, initial strategy, and command mode.
3. Perform a 360-degree perimeter walk-around to inspect basement windows, rear exposures, power lines, and victim locations.
4. Update scene strategy (offensive/defensive) over the radio following 360 completion.
5. Re-evaluate size-up factors continuously throughout the incident as fire conditions change or tactical goals are met.

Common Context & Application

Initiated by the first-arriving officer upon dispatch, updated upon scene arrival, and revised continuously as conditions evolve.

Frequently Asked Questions about Fireground Size-Up