Performing a size-up at an operation is always an important component of your strategic plan. A size-up can begin with the receipt of the alarm response or, prior to that, pre-fire plans and fire-prevention campaigns during inspections. The size-up should continue until the fire is placed under control and it appears the incident will not escalate.
There are many different types of size-ups for the variety of incidents firefighters respond to, including the 13-point size-up (which I will discuss in an upcoming article), strip mall size-up, and others. The issues vary along with the type of incident being addressed during your size-up.
The following is a list I use when responding to working fires at one- and two-family dwellings. I’m providing it just for the sake of comparison; I’m fully aware that you probably have your own size-up model or some other modified version. The bottom line is that if you address operation-specific issues in your size-up, you have a much greater chance of being successful in fighting the fire.
1: Alarm source: How was the alarm received — by phone, emergency personnel on the scene or occupants of the building? Some alarm sources can provide additional and more useful information than others.
2: Alarm assignment: Will a single unit be operating alone for an extended period of time? If so, that unit will be limited by resources at the scene and the (amount of manpower that responded with it). The incident commander should be aware of the number of units responding and evaluate the need for additional units.
3: Time of day: During nighttime hours expect a greater number of sleeping occupants and the possibility of a delayed alarm.
4: Type of occupancy: The structure might contain one family, two families or additional families or boarders. Some structures originally built as one- and two-family dwellings might be occupied by several families. Possible indicators include several mailboxes, additional electric meters, fire escapes, two front doors, numerous cars in the driveway or an exterior basement entrance. Even the attic could be serving as a residence. Look for a dormered attic, adequate height (about 7 feet), air conditioners at attic level, and normal-sized windows with drapes and shades.
5: Life hazard: The normally open interior stairs pose an extreme threat to the occupants during a fire. The stairs can rapidly build up with heat and smoke, making it difficult to evacuate occupants by using them. Be cautious and assume that additional families or individuals could be living in these dwellings, increasing the potential for trapped or helpless victims.
6: Windows: Inaccessible windows, smaller windows and windows that cannot be used for vent, entry and search may affect operations. These types of windows should be ventilated; however, it is important to coordinate any vent between the inside and outside teams. Porch or garage roofs may provide a working platform for vent, entry and search. Be aware when operating in these areas that fire can vent from below, placing a team member in a precarious position. Also, look out for window bars, which are more prevalent these days; the method of installation determines how difficult they will be to remove.
7: Construction: Platform construction limits fire extension. Balloon-frame construction lacks fire stopping capabilities between floors on the exterior walls, allowing for rapid fire extension. Wood trusses, wood “I” beams, and “C” joists can fail and lead to collapse when exposed to fire.
8: Roof Design: Firefighters’ outside ventilation positions are predicated on whether the roof is flat or peaked. Members assigned to outside ventilation positions can proceed to a flat roof dwelling and provide initial vertical ventilation. Otherwise, in a peaked roof dwelling, roof operations are not usually an initial tactic. This allows additional members to perform vent, entry and search.
9: Street conditions: Overhead wires, trees, narrow streets and houses set back from the street could interfere with apparatus placement and laddering operations.