The Thermal Imager And Accountability

At most incidents, even relatively small ones, chiefs and officers face a difficult task of maintaining accountability for firefighters working at the scene. A number of tagging and marking systems are available to assist fire officers in tracking firefighters. A thermal imager (TI) can be an excellent tool to assist in this task, especially when visibility is poor.


Probably the best way a TI can help an officer with accountability is to monitor exactly how many firefighters are operating in a sector. Especially in the early phases of an incident, when companies are still arriving rapidly and deploying, officers can quickly lose track of how many people are under their watch. By regularly scanning the area with his TI, a sector officer can monitor the "head count" of those operating with him. This type of numbers-based accountability can help officers recognize sooner when firefighters may be separated or lost. It can also help find "missing" firefighters equally fast, as an officer will notice the extra firefighter within his of her view.

As always, officers using the TI for accountability must remember the limitations of the technology. The TI sees heat signatures of items and does not see visible light; therefore, it cannot differentiate colors of like items of a similar temperature. While the TI can be used in a "stand-alone" manner for accountability, it will most likely be used in conjunction with other tasks. Consider:

  • Shapes are easily identified with thermal imagers. Some fire departments have had success using different helmet styles to identify probationary firefighters from experienced ones: recruits receive contemporary helmets and transfer to traditional helmets after their probationary (or training) period. An officer using a TI in this system would easily identify the number of experienced firefighters working inside a structure.

Practice Makes Perfect

Consider using thermal imagers during live-fire training exercises to enhance training, as well as accountability. Not only is it great practice to use the TI during a burn, it has tremendous advantages for the training staff. An instructor equipped with a TI can monitor the entry, movement and activities of trainees. This can be especially important with recruits who are still becoming comfortable operating in zero-visibility while totally encapsulated.

By viewing the scene with a TI, the instructor can also monitor the location of safety crews and verify their condition. Because the TI sees heat, firefighters who are exposed to high levels of heat will appear in lighter shades on the TI display than those firefighters who have not been exposed. This level of accountability helps ensure that firefighters are cycled in a timely manner through interior positions, and that equipment and personnel do not suffer any undue stress.

Reflections can pose challenging issues with accountability, as officers may be tricked into counting firefighters that are not present. Because reflections can cause significant problems with TI use and interpretation, firefighters and officers should practice around the fire station, and elsewhere, to understand different reflective properties. Practice looking for clues that an image is actually a reflection:

  • A portion of the image is bordered by a frame, indicating a mirror, window or glass door.
  • The image appears similar to the user's surroundings or situation (i.e., three firefighters near a bed in a room).
  • The image mirrors activities occurring near or around the user (i.e., two firefighters pulling a ceiling, looking for fire extension).

Table Talk

Company officers can do several simple drills in the firehouse. First, they can use their thermal imager to determine what identifying marks and details are visible on their firefighters' gear. Does their TI differentiate enough (under ambient conditions) to identify unit numbers or decals on fire helmets? Can a firefighter's name on his turnout coat be read? Keep in mind that in many cases, the answer to these questions is, "No." It will be the rule, rather than the exception. This does not mean the department has a "substandard" TI; it just means that all of the temperatures are too equalized in the environment for the TI to detect a difference.

Firefighters can discuss options they have to make their gear unique, and therefore recognizable, for their officer. For example, firefighters who carry wooden wedges on their helmets can all carry them on the left, pointed toward the rear, to help identify them as a unit. Remember, shapes will be more evident with the TI under normal fire conditions.

Final Report

Tracking individual firefighters with a TI can be challenging. Unique identifiers may blend into the thermal scenery, making individual identification difficult. But, fire officers can use TIs to track firefighters in their overall tasks: an officer can verify that he entered with four members, advanced to the attic with four members and there are four members working in the attic. As always, planning and practice will greatly contribute to the success chiefs and fire officers have in using the TI to maintain firefighter accountability.

For more ideas on using the TI for accountability, visit the Technology Section of

Jonathan Bastian is a thermal imaging training consultant for Bullard. He is certified as a thermal imaging instructor by the Law Enforcement Thermographers' Association (LETA), the international public safety organization specializing in thermal imager certification and training. He is also the author of the FD Training Network "FireNotes" book, Thermal Imaging for the Fire Service. Educated at Brown University and licensed as a high school teacher in Illinois, Bastian served 12 years on the North Park, IL, Fire Department, including the last three as a captain. As health and safety officer, he led the development and implementation of the department's rapid intervention team SOG. Bastian is a certified Fire Instructor I and Firefighter III, and he spent 12 years as an EMT-I/D. He has taught classes on thermal imaging, rapid intervention teams and search and rescue operations. He is currently a public safety official in Central Kentucky. If you have questions about thermal imaging, please send them to