Which statement describes when the size-up process begins?

• A. Before an incident is reported and continues throughout
• B. After first-arriving resources arrive and continues throughout
• C. Before interagency aid arrives and after reciprocal payment is taken
• D. After the incident is terminated through the post-incident analysis process

Answer: (A)

Size-up is an ongoing assessment that starts before anything is reported and continues through the entire incident. It begins in the pre-incident phase—during planning, training, and building/area risk assessments—so responders have a clear picture of potential hazards and resource needs even before receiving a call. As the incident unfolds, information from dispatch, witnesses, and arriving units is continually integrated, and decisions are updated to reflect changing conditions, priorities, and tactics. If size-up waited until first-arriving units or outside aid arrived, critical decisions would be delayed, and if it started after the incident ended, there would be no opportunity to influence actions during the event. So the correct description is that size-up begins before an incident is reported and continues throughout.