Firehouse March 2004

Firehouse Magazine, March 2004
Thermal Imaging & Incident Size Up
By Jonathan Bastian

Incident size up is a critical first-step that helps ensure firefighter safety as well as the successful conclusion of an incident. Effective and proficient use of a TI during incident size up requires several key points be incorporated into regular training.

Essentials

For the TI to be of any use during size up, it must actually come off the apparatus. In addition, the user must be comfortable carrying and using the TI . To ensure this happens in “real life” incidents, fire departments should take the following steps:

The department’s SOGs must incorporate thermal imager use. The SOG should identify the person assigned the tool and specify that the TI will be taken off the apparatus at every scene. Do not limit use to only fires or to non-EMS runs. In most departments, working structure fires are 10 to 20% of their runs; 70 to 90% are EMS runs. TIs can help at certain EMS scenes, and regularly carrying the TI reinforces the habit.
The TI must be within easy reach of the assigned user. If the company officer is assigned the imager, the TI should be mounted near the officer’s seat. A TI in a compartment or a trunk is used rarely in size up.
Most firefighters realize that how they train is how they will perform. During every training evolution, the assigned person must carry the TI. The user must be comfortable performing all of his/her normal tasks while carrying the imager. Climbing a ladder with a TI hanging from an SCBA or draped over a shoulder can be frustrating if it is not practiced.
Standardize how the TI is carried. Many TIs are supplied with a carrying strap. Test this system and develop the most convenient method of using it that will satisfy the department’s operational needs. Make sure that other fireground tasks can be completed while carrying the imager.

Since smoke and steam are coming from every window, where is the seat of the fire? Where has it progressed? Is it already in the attic, or still in the walls? Early use of a TI can help with the size up and evaluation. During this Jan. 7 incident, a thermal imager assisted in the rescue of the resident. Photo courtesy Charlottesville (VA) FD Fire Marshal Ben Powell.

Practice makes perfect

Several drills can develop a user’s proficiency with a thermal imager. A key skill to gain is image interpretation, which requires very frequent use of the TI. Walk around the firehouse looking for odd or out-of-place heat sources. Discuss how and why the image appears as it does. At night, stand outside the firehouse and look at the neighborhood. Practice recognizing construction features; analyze the effects of the sun and weather on the image:

Are certain parts of a building hotter after a summer day?
Does a cold rain change the “normal” signature of the building across the street?

Consider the effects of building construction on what is displayed on the imager:

Is heat escaping from the building and what might that suggest about construction?
Are studs visible or is a masonry wall hiding internal heat due to its mass?
How is the building’s mass affecting the image?

By examining local structures, users can learn what a “normal” building looks like under non-fire conditions. This can serve as a basis for comparisons at a fire incident.

Table talk

While sitting around over coffee, TI training can occur as well. Quiz members on the thermal imager SOGs. Brainstorm on different types of scenarios, and when and where a TI can be used to help size up an incident. How can the TI help size up these scenes:

An auto accident?
A tanker truck rollover?
A suspected arson?
A chemical spill at a factory?

On Scene

Applying the skills and practice in real life is the final exam. Figure 1 is a digital image from an actual structure fire. Figure 2 shows the key points highlighted. Before examining figure 2, “read” what figure 1 is showing. Try to determine how advanced the fire is, where it is and where it is going. Decide if this is a building that can be “saved”.

This image is a digital capture from a thermal imager. It shows the A side of a structure fire at a carpet retailer (right occupancy) with exposure to a restaurant (left occupancy). Heavy black and brown smoke is pushing from the carpet store’s door (side D). The building is a Type III structure, approximately 60’ x 60’ (18.5m x 18.5m). The first-due engine and truck have just started operating and hydrants lines are being laid out. The weather: rain and 55°F (12.5°C). Photo courtesy of Bullard.

This image shows the key points in the size up. 1) The roof is extremely hot, especially given the weather conditions. Heat has spread along the red curved line, showing that the fire is traveling above the drop ceiling and is working into the restaurant. 2) The hot windows at the carpet store show heavy heat inside the building. This has not spread completely into the restaurant. The windows are very white, down to about 3-4’ (90-120cm) above the ground, showing that the heat layer has dropped significantly. 3) Heat columns are pushing from the door on side D. The bright white below the heat columns could be fire hidden within the smoke. Photo courtesy of Bullard.

Final Report