Thermal Imaging in Wildland Firefighting

Who in the world would knowingly choose a career that offers hours and hours or days and days of strenuous physical labor, limited clean air, no access to large-diameter hoselines, occasional high-altitude working environments, a tinfoil pouch to serve as personal protective equipment (PPE) and fires measured in acreage as opposed to square footage? The wildland firefighter, that's who.

I have a great amount of respect for the wildland firefighter. It is truly a job that few people are physically capable of doing. To top it off, these men and women accomplish the task without the assistance of a large truck full of equipment. Instead they opt to work with whatever tools they can carry in. Fighting a multi-acre fire with a small shovel takes a special breed indeed. And, although wildland conditions can be drastically different than structural fires, a thermal imager (TI) can still be a valuable tool in wildland firefighting.

When used properly, thermal imagers can help wildland crews more effectively monitor fire conditions: keeping closer tabs on the flank and head of the fire, placing personnel in key areas to create control lines, enhancing safety during firefighting and improving the control of prescribed burns. Wildland firefighters can also use Tis to enhance their safety when navigating through smoke.

Thermal imagers are primarily being used in wildland firefighting in five ways:

  1. Monitoring the flank and head of the fire from the air - With a thermal imager, the fire's location and progress will be evident from an aerial position, regardless of sunlight or the smoke conditions. The TI enables precise monitoring of fire progress that would not otherwise be possible. The ability to monitor fire progress in low light or heavy smoke can help crews begin operations earlier in the day and end later in the evening, increasing efficiency. Continually monitoring the fire for growth, decay or movement can help predict travel and behavior, despite prevailing weather This benefit can help incident commanders make more informed decisions.
  2. Placing and monitoring personnel - In large operations particularly, the placement of limited personnel is critical to gaining control of the fire. With the enhanced visibility thermal imaging provides, wildland firefighters can be placed in key locations for construction of control lines. Proper placement enhances the ability of firefighters to protect exposures, including structures, threatened habitats and critical infrastructure. As ground crews deploy, airborne supervisors can monitor their locations and ensure a coordinated and effective response.
  3. Monitoring dangers and extinguishing hot spots on the ground With proper training on image interpretation, firefighters can use thermal imagers to monitor fire movement on the ground and in the trees above them. The direction and volume of firebrands can be tracked and monitored with a thermal imager. With practice, firefighters can identify snags, thereby helping to improve safety on the job. During mop up, crews with thermal imagers can scan burned areas to help ensure that the fire is out, basically overhauling an area the size of a football field.
  4. Managing prescribed burns - Controlled burns are critical to reducing fuel load and improving manageability of wildland fires. Using the heat picture on the TI, wildland firefighters involved in prescribed burning can monitor the direction of fire spread and manage mop up more effectively. A thermal imager can also reveal the travel of firebrands and embers from a prescribed burn, making spot fire easier to locate and control of the overall burn easier to maintain. This information lets firefighters protect exposures and keep these burns in a controlled state.
  5. Navigation - When firefighters travel by ground during active wildland fires, their vision may be obscured by smoke. A thermal imager used from a vehicle can assist the driver in navigating safely through thick smoke, avoiding fixed hazards as well as firefighters on foot. Firefighters on foot can use a TI to help identify safer travel routes based on terrain or fire movement. This can help crews move safely and effectively when smoke obscures their vision.

Firefighters should be aware that thermal imaging technology is not a replacement for basic tactics. There may be times in mop up when a thermal imager cannot detect a hidden heat source, such as when the heat exists deep within a tree trunk. There may also be times when the image on the TI appears inconclusive to the user. When the TI is not providing as much information as desired, firefighters should rely on traditional techniques. If there is still doubt after using the TI along with traditional techniques, firefighters should err on the side of caution.

As with any other application of thermal imaging, planning and practice are the keys to effective technology usage. Firefighters must not only understand what they are seeing on the TI, but they must learn how to use this information seamlessly with the topographical and locational information they already employ on the job.

BRAD HARVEY is the Thermal Imaging Product Manager at Bullard. He is a veteran of public safety as a firefighter, police officer and paramedic and is certified through the Law Enforcement Thermographers' Association (LETA) as a thermal imaging instructor. Harvey has worked as a high-angle rescue instructor and is a certified rescue technician and fire instructor. If you have questions about thermal imaging, you may e-mail him at