Size up: A concentric-circle approach

Perform the 360-degree size up in layers to avoid missing important information

They say that sinners make the best preachers, and that might be the case for me. I learn through bruising.

I've made the same mistake twice during the last month at structure fires. I didn't get a look at all sides of the building; I didn't perform my own 360-degree size up.

When I'm the first-arriving company officer I make this incredibly important task happen. At that point action plans are still being formulated (either in my head or in that of a chief if one is on scene), and the gap to get the task done seems somehow wider.

Hopefully officers have taken the time to learn about their neighborhoods, the construction types, occupancy and usage. But even if they haven't, the first-due officers should see at least two sides as they drive up and a quick walk will give them the other two sides of the building.

By the time I've done this assessment and come back around, my crew is ready and I can confirm for them and our incident commander what I've seen before we enter.

Late arrival
However when you're not on the first-due truck or engine, the parking spaces tend to get filled pretty quickly. The chance to catch the side and front of the building is pretty much lost, as you cannot drive in front of the building. This means that your walk around will actually be just that — a walk around.

Many of us are used to having a chief arrive before us, which can lead to complacency when it comes to the walk around. But at some point you'll arrive first and have to do the size-up. If you wait until that day to learn good size-up techniques, you're likely in for a big and unpleasant surprise.

When you're not first on scene the action plan tends to be in full swing and you're likely trying to play catch up with the tasks being directed to you by command. This is when it's easiest, for me at least, to lose track of the fact that I must complete my walk around. 

We know from reading NIOSH/FACE reports that not doing a 360-size up is a clear, and addressable, factor in many line of duty deaths, injuries and close calls. Yet, too often the bright and shiny objects distract us on our arrival. 

Snapshot in time
We think we know from first glance where the seat of the fire is and the quickest way to it. We think we know where the stairwell is that we'll need to protect, or even the perfect place to perform the vent. But the reality is, without our own review, we really aren't aware of much other than a snapshot in time.

I like to think of the walk around as concentric circles with the building at their center. I move from the street inward and look for the utilities both for our safety and for truck work. I look for overhead and underground utility service, including gas, electric and multiple services. I look for things that aren't always obvious from the street.

In my part of the world, garages are in the back yard, making the back door, not the front door, the most common entrance. Always remember that residents will try to escape via the path they use the most.

I look for construction types. Although many homes are lightweight construction, not all are. I check to see if the construction type seem in sync with the entire building. Is the fire in the light-weight add-on or is it in the balloon frame original section of the building?

If you are unsure what the older homes in your district were supposed to look like, try a Web search on Sears & Roebuck homes. You might be surprised how many houses you recognize and how many floor plans you can find.

The outside edge of the circle provides a view of exposures, not just what they are, but what they are made of and what they house. You may find another residence, a business, a garage or the homeowner's at-home candle making workshop.

This is also the time to look for grade changes from front to back. Is what looks like a two story from the street really a three story with a walk out? Is the fire the first-arriving called on the first floor really a well-seated fire in the basement?

A recent UL fire study (along with anecdotal information from the field) indicates that some deep-seated fires after their first decay (vent limited) stage produce very limited smoke to the exterior. This limited smoke can fool us about the size of the fire, but other indicators on the walk around can clue us in.

Finally, when you're not the first arriving unit your quick assessment can help command determine if their action plan is working. They might have looked at the Charlie side on their arrival and things looked calm. But on your walk around 3 minutes later the calm has turned to chaos.

Sharing this observation with command might be just the information needed to re-evaluate the plan before a team is committed to action.

Quite frankly most of us are geared to action, and taking the time for this kind of information gathering can seem costly. But having the right information, and the right and updated action plan makes all the difference.

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