The "Five Deadly Sins" Of Thermal Imaging

Every month, this column emphasizes how a thermal imager can make a firefighter’s job easier and safer. This month’s column is part one of a two-part series concentrating on training firefighters to use their thermal imagers in a safe, appropriate and competent manner. Departments must train on general safety principles to ensure that members do not become overconfident with or overly reliant on thermal imagers. Complacency is a killer and to avoid complacency, you must have a keen understanding of where problems can come from so you learn to avoid situations that can lead to tragic consequences.

As with any tool in the fire service, if a thermal imager is misused, the consequences can be disastrous. Firefighters using thermal imagers must understand the five general risks of their use and how to avoid traps. There are many other areas where mistakes can occur, but these five are the most common areas I have seen.

The “Five Deadly Sins” in thermal imaging are:

1. Standing and walking in unsafe environments

2. Abandoning traditional safe-search techniques

3. Advancing at an inappropriate speed

4. Misinterpreting images

5. Misapplying technology

Deadly Sin 1 – Standing and walking in unsafe environments. Firefighters are trained to stay low and crawl in hostile environments to avoid exposure to heat and unseen dangers while keeping a firm, four-point stance on the floor. Thirty years ago, firefighters had to stay low in fires – their protective equipment was not advanced enough to provide thermal protection from aggressive fires. Modern turnout gear, though, is durable enough to let firefighters stand and walk in all but the hottest environments.

Today, the inability to see is the primary force that pushes modern firefighters to crawl. To avoid injury, firefighters crawl to navigate around furniture and debris, up and down stairs and around any hazards that might exist in a structure. When equipped with a thermal imager, however, firefighters have the ability to “see” their environment, which fosters a natural tendency to assume that a structure can be safely navigated on foot.


Working in hazardous environments

The tendency to stand and walk in hazardous environments can have dangerous consequences. Superheated gases are still present and pose serious risks to firefighters and their equipment. Certain hazards may be difficult to differentiate on a thermal imager, such as a hole in the floor of an abandoned building or furniture in a temperature-stable room. Thermal imagers also lack a critical aspect of human perception: peripheral vision. Peripheral vision helps firefighters identify structural risks even when they are not staring directly at them. A thermal imager will not detect a potential risk unless it is directed at the risk; this gives the user tunnel vision.

Firefighters can take two key steps to battle the urge to stand and walk. First and foremost, don’t let it happen! Train frequently with a thermal imager in dark and smoky conditions, ensuring that members do not assume that their ability to “see” is an indicator that they are in a safe environment.

Second, teach all users how to overcome the thermal imager’s restricted field of view and avoid the tunnel-vision effect. Since an imager has no peripheral vision, the user must scan the entire room to evaluate fire conditions and search for victims. The simplest search method is a “Z-pattern.” The user moves the imager from shoulder to shoulder, scanning near the ceiling, then across the middle of the wall, then down at the floor. The shoulder-to-shoulder, high-middle-low scan creates a Z-shaped pattern. Consistent use of this procedure ensures that the majority of the room is scanned by the imager and gives the firefighter a complete view of the structure, room by room.

Deadly Sin 2 – Abandoning traditional safe-search techniques. The restricted visibility from smoke that firefighters typically experience in structure fires helps deter them from overextending themselves; however, a firefighter with a thermal imager does not have restricted visibility. The ability to “see” can raise the confidence level, often tempting the firefighter to engage in higher risk operations or to ignore danger signs.

Firefighters cannot confuse “visibility” with “safety.” Operations that are conducted with a hoseline or ropeline without a thermal imager should be conducted with a hoseline or ropeline even with an imager. Search patterns must still be consistent and easily reversible. At any point, a thermal imager could become unusable from loss or failure and firefighters must always be able to navigate their way out – with or without a thermal imager. Firefighters still must keep a mental map of the structure, ensuring they are aware of their approximate location inside the structure as well as their primary and secondary egress points.

To address safety concerns in hostile environments, supervisors must ensure that firefighters perform searches with and without a thermal imager. By incorporating the imager with other operations, leaders can emphasize that it is a tool to help with that function, not intended as a standalone operation. All training evolutions must be monitored by instructors or supervisors. Ideally, this is done with another thermal imager, so leaders have a means of verifying that safe habits are reinforced.

Thermal imager-based training should include random simulations of equipment failure. Instructors can take the imager (simulating loss) or remove its battery (simulating failure), then order the firefighters to continue operations or evacuate. By emphasizing both options, firefighters will learn that they can continue their work despite the loss of a thermal imager. By training regularly without thermal imaging as an aid, firefighters will also remain proficient with their standard skills in the event that no imager is available at an incident. n

Next: Three more “Deadly Sins”