More on Size-Up


Last month we started to look at some of the incident size-up process. We discussed how important and sometimes difficult it is to do the initial and ongoing size-up—particularly in the exciting and time-compressed beginning stages of fire operations. We must become size-up students (whether we want to or not) because we are going to size-up school every time we respond, arrive, and somehow try to evaluate what is going on. Size-up is a basic responsibility that starts with our initial arrival and then requires us to continue to gather and manage accurate, timely, tactical information throughout the incident so we can maintain effective and safe sustained operations.

A major part of the size-up process, particularly for the incident commander (IC), is to understand the basic sources and forms of tactical information and to become skillful in how to use and integrate those different kinds of input to make up an initial and ongoing “fireground picture” of what is and what will be going on. The IC must connect the most effective method of gaining information to the location, nature, and timing of the factor that he wants to know about.

The IC makes this connection (method/factor) by mixing and matching the four basic critical factor-“gathering” methods listed below to match the desired information factor. This becomes an acquired (study/practice/refinement) ability that produces a steady stream of strategy and incident action plan (IAP) information. The approach uses and mobilizes the components of the entire fireground organization to assist in doing their part in that effort based on their level, position, and function. Let’s look at those basic information forms.




Previous experiences and lessons become a major incident management information source. Having seen actual conditions, developing an action plan, and then living through the outcome of how that action worked (or didn’t work) is a very practical and personal way we use to evaluate where the current incident is now and to anticipate where it is headed—simply, we apply the complete set of lessons we learned at the last size-up to the next size-up.

The classic “slide tray” in the brain (Dr. Gary Klein, Sources of Power, Cambridge, Mass: the MIT Press, 1998) fits into this previous experience information category. We evaluate current conditions by connecting what we are seeing right now to tactical activity (fires) we lived through in the past. That frame of reference of previous fire experience also involves recognizing a previous pattern of how conditions evolve and applying that strategic and operational pattern to current incident conditions. Using this pattern-based approach eliminates a lot of the mystery of how fire progression occurs and makes the outcome of current fire behavior more understandable. We are safer and more effective if we can more accurately predict what will happen next.

Refining the ability to effectively utilize our previous experience by putting what we lived through in the past in “the bank” is a big deal. Applying this historic system relates to overall strategy development and incident action planning and to functional behavior routines on every level. Those who are able to do this pay attention, look, and listen a lot so they are always learning and become smart old/young firefighters; those who can’t are the ones we describe as “one year of experience 20 times.”




Visual observation and inspection are important for gaining that information. They involve looking at the situation from outside, inside, and around the incident site. This “look at it” information form involves the critical, perceptive capabilities of the IC and the team. This is the most common information management form used for initial and ongoing incident evaluation by the IC and the most natural way action-oriented responders get information about the conditions with which they are dealing—simply, firefighters are great spectators.

Looking at the world around us is a major (and very natural) way we stay connected to what is going on in that world. When we get on the fireground, that visualization becomes even more powerful. There are many times when very, very profound and hugely distracting visual things are going on: big flame fronts, huge smoke huffs and puffs, stuff collapsing, humans at their best/worst, and so on. We must develop the ability to look past the confusion to pick out and go to work on the significant critical factors.

The IC must understand how important it is to develop effective visual discipline. Quickly evaluating the overall scene and then picking out and prioritizing the critical factors require study, thought, and practice. Along with doing the evaluation, the IC must mentally connect the result of the size-up to the basic tactical priorities and then mentally put the assignments in the order of those priorities (rescue/fire control/property conservation).

Cagy, experienced ICs just naturally look at structures/fire areas as they cruise around on their (nonresponse) appointed rounds and mentally lay out that evaluation—priorities, assignment, routine—until they can do it in their sleep. When I was a battalion chief (Ben Franklin era), I mentally laid out a second alarm on every significant structure/place in my battalion five times.




The IC assigning personnel to standard decentralized geographic and functional organizational assignments all over the incident site many times acquires critical information not directly available visually to the IC from the fast action or command post position. It comes from operating elements and sectors dealing with specific incident problems and locations that then transmit their information-oriented reports back to the IC. It also can come from other sources, such as owners/occupants, technical representatives, other agencies, law enforcement, or press helicopters circling (noisily) above.

The effective use of recon information becomes a major capability that facilitates effective command positioning. Instead of going to see directly in person, the IC stays in the command post, makes standard (and special) assignments that cover the entire incident and then receives back information reports on critical factors, and translates that information into strategic and IAP intelligence that keeps operations effectively and safely connected to the current and forecasted status of the event.

A major part of how effective recon is depends on the language used to exchange information. The team must use common, agreed-on words and terms that mean the same thing to all parties. We must develop more effective “vital signs” that relate to structural firefighting—the wildland firefighters have done a good job of producing a common lexicon for reporting and responding. We should also use the doc/paramedic and pilot/air traffic controllers as communications/information-exchange models.




Formal preincident planning and informal familiarization activities are important information sources. This predetermined and prepackaged intelligence increases information that is quickly available visually or that requires reconnaissance assignments to obtain. Preincident planning materials include reference information that comes from information-gathering tours, books, databases, information services, technical sources, and advisors.

A mobile computer terminal (MCT) is now becoming the modern standard response vehicle “dashboard.” Managing the electronic delivery of stored and online information is a very natural activity for today’s firefighter/officer. An almost unlimited amount of information is now available in a nanosecond format. The current challenge for us is to gather and package the critical characteristics of tactically significant occupancies and areas in a format that is usable on the fireground. It will be interesting to look in on the next generation of our troops and see how they are managing incident information on their “FireBerry.”

As operations expand, and the more the IC moves to the strategic level, the more recon from sectors, reference information, and staff support are balanced with previous experience and visual information. Factors and information assumed by the IC in the initial stages of the incident must be confirmed to base the IAP on better and better facts. The IC continues throughout the incident to use and balance all the standard information sources.

Virtually all the rescue and firefighting decisions the IC (and everyone else) makes are based on accurate, timely size-up information. The action we create can only be as good as the decisions we develop, and the decisions can only be as good as the information on which they are based—so to be effective and safe, the entire rescue and firefighting operation must produce a steady stream of tactical and strategic intelligence. Many times when the fire injures/murders a firefighter, it is the result of an “information gap” that somehow interrupted or interfered with the steady flow of critical information from around the fireground up to the command post.

Fires routinely hide from, deceive, and confuse the IC. The IC must set up and instantly apply an effective information management system that gets and stays ahead of the chaos the fire is creating. (I asked a smart old IC what he was doing one dark and windy night as he was commanding a very serious fire/collapse situation. He very calmly told me, “Chief, I’m just takin’ the edge off chaos.” He basically stopped the fire where he found it.)

Being out of information sometimes can be more serious than being out of water.

Retired Chief ALAN BRUNACINIis a fire service author and speaker. He and his sons own the fire service Web site


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