Sizing Up for Structure Fires


As volunteer firefighters, we respond from home, work, and our private lives to perform our duties. As we shift gears from one mindset to another, many things go through our minds en route to the firehouse or scene. On the fireground and in practice training, we sometimes forgo the most important aspect of incidents. Although we consider tactics (who should be there? Will I make it inside?), one thing that often gets overlooked and short-changed is size-up.

The area in which you volunteer and the makeup of your district or fire protection area (urban, suburban, rural, commercial, industrial) dictate how much fire action you see (or don’t see) throughout the course of a year or your career. These experiences with fire help us to develop a mental bank filled with images and tactics we can use to fight the next fire. Much like snowflakes and fingerprints, no two fires are alike. Given this statement, all of these mental pictures are enhanced or, for those with no experience in fighting a fire, created on the practice grounds.

We practice our skills for patient care once a month; we practice our firefighting skills more often, which usually are hands-on skills, whether hoseline advancement, ladder placement, or extrication. All these skills are practical and are definitely skills that should be rehearsed to the point of our being able to do them blindfolded, but there are other skills that will get rusty with neglect. A firefighter’s skills of sizing up structures and, as Battalion Chief (Ret.) Dave Dodson puts it, “reading smoke” can be forgotten or become “rusty” if they are not practiced regularly. This skill set is integral for every firefighter on the fireground, no matter how experienced. Every level of firefighter, from probie to chief, should review these skills and practice them whenever possible.

Scene size-up, as every firefighter knows, is essential to a solid and SAFE resolution of an incident. However, scene size-up isn’t just a necessity at a fire scene; many times people think that size-up matters only during the course of a fire or some other outstanding event. In reality, scene size-up occurs at every call we go on, whether we think about it or not. Firefighters perform size-up at first aid calls by determining the type of occupancy, nature of distress, and so on. Size-up also is necessary at auto accidents with regard to vehicle damage, injuries, and other scene safety issues that might harm first responders or victims. For the sake of this article, we will focus on size-up for structure fires.

Structure Fire Size-up

As volunteers, the first thing that we must embrace as part of our size-up is attached to our belts. Our pager is the start of scene size-up. Newest to oldest members are given pagers, and they provide everyone, from the chief on down, with the same starting information. In my department, we refer to it as “the tones dropping.” Every time the “tones drop,” your size-up should begin with the nature of the call, the location, and what is being described. As you run out the door and jump into your personal vehicle, turn up the pager so you can hear further updates. Nothing is more embarrassing than to show up and not know what is going on.

There are several key items to remember while attempting to make a quality size-up. Remember, your size-up is a visual for everyone listening who isn’t there yet. Also, it sets the mindset of the operation for the dispatchers; other chiefs responding; mutual-aid departments; and, most importantly, your own firefighters approaching the scene. Some key items to remember when giving your scene size-up to dispatch are the following:

1 Make it concise. No one wants a size-up the length of a novel. People will miss important facts and staying on some radios for that long may cause you to time out between transmissions. The example below is short and to the point. Everyone listening knows what they are heading toward without wondering if they missed what color the siding is.

Incident Commander: “Dispatch, I’m on location, 2½-story wood-frame residence. Heavy smoke and fire showing from the Bravo side. It’s reported all residents are out of the house.”

2 Be accurate. When you are the first person on scene, either with a radio to incoming units or a cell phone to your dispatch center, it is important to be accurate with your initial report. Pulling on scene and just saying, “We have fire blowing out the windows!” does nothing for anyone else responding, except to confirm that you have a fire.

3 Watch your tone of voice. Your tone of voice can determine the outcome of your operation. If you give a size-up that is energetic, wild, and unhinged, that is how your operation will go. Firefighters arriving on location will be too geared up for action and will not take notice of the little things. That leads to mistakes and injuries. A calmer and more controlled size-up provides incoming units with control and subconsciously slows them down once they are on scene. (Remember, we are firefighters. Unless there are extenuating circumstances, we should not be surprised when we see fire.)

Now that we have arrived on scene and a quality size-up has been transmitted, the next steps are critical as part of the overall evaluation of a fire size-up.

  • Conduct the “360.” This is the most important step for a firefighter, an officer, or a chief during a scene size-up. Do it before crews enter the building so if something out of the ordinary arises, tactics can be changed before members have been committed to the building.
  • Identify life hazards. This is an ongoing function throughout the fire. Dispatch may inform you that all people are out. Once on location, confirm this with a household member. During the course of the operation, continually reevaluate to make sure that fighting this fire isn’t further harming your members. There is no shame in going defensive if the fire has the upper hand.
  • Identify resources. As volunteers, we rely heavily on mutual-aid resources to supplement ours, especially during a daytime fire. As you are assessing the building, your 360 should include whether or not you have enough people and equipment coming. Do you need more?
  • Assess effectiveness. Are the tactics you’re using to put the fire out keeping it at bay, or are things getting worse? Remember, once you fall behind at a fire, you can never catch up.


You can practice size-up on cold winter nights in your firehouse. Set up a projector; log on to any video site that has fire videos; and watch the multitude of videos available on structure fires, car fires, or any other type of fire you feel your members should prepare for. You can also go to search engines with image searches and look at pictures to create a mental image and help develop your members’ vocabulary for giving a proper size-up.

Your initial size-up is the baseline for the fire. From here, conditions change in one of two ways: Either the conditions improve, or they get worse. Clear communication and proper size-up will help influence your tactical decisions so they are the safest for your firefighters, as will training on how to conduct accurate and complete size-up and becoming familiar with the structures, layout, and construction types in your district.

SEAN WILKINSON is a seven-year member of the Snyder Fire Department in Amherst, New York, where he is a captain, a live fire instructor, and a public safety dispatcher with the Amherst Police Department. He has a B.A. degree in history from the University at Buffalo (State University of New York) and is completing the requirements for a master’s degree in education from the University at Buffalo.

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