Fire is a very hostile atmosphere for most people, including firefighters. When you have smoke that is so thick that you can’t see your hand in front of you, and you couple that with high heat, it’s an atmosphere that’s enough to scare the best firefighters. The key is being able to rely on the right tools that can help you get through that situation.
When you have a tool that allows your team to see through that smoke, it creates a comfort level that allows you to do your job more efficiently and safer than ever before. Thermal Imaging cameras or TIC’s have been around for a long time now and have been used in the fire industry for many years. These have always been handheld cameras but with technology advancement, the cameras have become much smaller with better resolution making them ideal to fit onto a drone.
Fire departments have always kept an eye on how new technological developments can enhance the safety of their team members and victims during firefighting operations and one of the latest developments is the use of drones fitted with a FLIR XT2 IR camera for a Birdseye view of either structural fires, forest fires or grassland wildfires.
Thermal imaging drone systems today provide firefighters with information that wasn’t readily available just a few years ago, such as structural integrity of a roof, true primary heat source location (versus chasing smoke), and drastically reducing the time for fighting the fire.
An Infrared camera can see through smoke making it a fantastic tool to be able to fight the fire. Add it to a drone flying high above the situation and the camera can see the fire crew on the ground and so can keep them safe, as well as being able to see the head and edge of a wildfire and allows you to see where best to position the fire crew to fight the fire.
The number of pilots and drones used on a fire varies based on the circumstances, but the average is two pilots, two drones and two visual observers. On small to medium structure fire, one drone team will often suffice, but on a very large wild fires then 4 or 5 drones may be deployed along the fire front with a fire crew fighting the fire.
Using a FLIR XT2 and DJI drone on a building or structure allows the operator to get a good idea of the roof integrity that a crew might be working on and so they are able to see how the fire has progressed through the building and how likely the roof is to cave in. They are also able to see how the smoke and fire travelling through the building or structure and so gives them information where to make an entry or where survivors might be located. The XT2 drone system can also be used in Hazmat conditions giving information about levels of liquids in vessels and tankers as well as detecting leaks before the crew enters the area.
Once the fire is out the drone can also be used for hot spot detection for mop ups showing the location of smouldering areas and tree stumps where the fire might flare up again. Thermal cameras are perfect for this application as they can cover such a wide area very quickly and the drone operator can guide the mop-up crew to the exact area or specific hot spot that may have been missed without an IR camera present.
I have heard many times stories of how a mop-up crews thought they had put out a wildfire or forest fire only to return to the same fire another 4 or 5 times that night due to flare-ups and with the IR camera on a drone, these areas can now be seen and extinguished once and for all.
The drone IR system can also help with finding missing persons and suspects. The thermal imaging capability allows the user to locate people where they otherwise would not have been found and in many cases, darkness becomes an advantage rather than a detriment due to less background noise from the sun. During a recent incident, an armed robbery suspect had scaled a two-story building to evade the K9 and ground search police. He was found hiding on a roof under an overhanging tree limb with the DJI M210 drone and the FLIR XT2 IR Camera. It should be noted that proper use of the FLIR Isotherm technology can greatly improve the chances of a find. The camera also now has a temp alarm, Heat Track, MSX, Isotherms, many colour pallets and temperature measurement.
FLIR recently launched the next generation drone camera called the FLIR XT2 and coupled with the DJI Matrice 200 series drone you have a state of the art aerial system to take into any fire application. The XT2 comes in a choice of either a 640×512 or 336×256 IR resolution and depending on the IR resolution can be purchased with either a 9mm,13mm,19mm or 25mm lens. The XT2 also has a built-in 12MP digital camera and is fully radiometric allowing the images captured to be analysed after the event on a PC and any pixel in the image can then be measured in deg C for the correct temperature of the object. The camera comes in either a 9Hz or 30Hz frame rate.
The FLIR / DJI drone system increases safety for the firefighter and /or police officers and makes them more effective and efficient at what they do. A fire department wouldn’t buy a water hose without a nozzle and a police department a firearm without ammunition. The same logic should apply to the thermal imaging equipment attached to a drone.
FLIR Handheld TIC’s
In addition to the drone system, FLIR also has a large range of handheld TIC’s from NFPA certified cameras to basic TIC’s for bushfire and Volunteer brigades. Professional full-time firefighting teams have been using thermal imaging cameras for structural firefighting ever since the technology was available. But now with the new cameras from FLIR, things have changed dramatically.
The thermal cameras allow you to scan an area very rapidly, which is of crucial importance. With older models of TICs, you were only able to search inside a structure, whereas with the new FLIR cameras, you have sufficient resolution to allow you to scan the inside as well as the outside of a building, so you have a complete idea of what is happening. Scanning the outside of a structure before a fire crew enters has become a standard procedure for many fire teams as it can guide them exactly to where they can be most effective.
Choosing the right thermal camera model is often a complex exercise of spec comparisons, such as image resolution, camera sensitivity and temperature range. Simply put, the temperature range indicates the minimum and maximum temperatures that a camera can measure. As an example, FLIR’s K-Series cameras accurately measure temperatures between -20°C and +650°C. Other brands will measure maximum temperatures up to +1,100°C, tempting the unwary buyer into a story of ‘more is better’. Although these numbers might seem spectacular to an equipment buyer, in today’s state-of-the-art thermal imaging technology, high temperatures come at the expense of image quality. And for a firefighter, image quality can make the difference between life and death.
What you should know about high-temperature ranges in TICs
1. Dangerous loss of image quality
The term ‘temperature range’ is a bit misleading. What is more important for a firefighter is the Effective Temperature Range (ETR), which measures the range of temperatures that a TIC can view while still providing useful information to the user. Specifically, extreme heat in the field of view tends to inhibit a TIC’s ability to discern surfaces having intermediate temperatures and details. This loss in image quality and reduction, in contrast, can have severe consequences for a firefighter, because there’s a chance of missing out objects that are located in the lower temperature range, such as victims or escape routes.
Firefighting cameras usually have a high sensitivity and a low-sensitivity mode. In absence of a fire, the TIC will operate in a high-sensitivity mode, presenting the thermal environment in all its detail. In the case of FLIR’s K-Series cameras, the high-sensitivity mode measures temperatures up to +150°C. In case of a fire incident, the camera will switch to low-sensitivity mode, which offers a well balanced and acceptable trade-off between lower sensitivity (less detail) and the ability to monitor higher surface temperatures. For FLIR’s K-Series cameras, low-sensitivity mode measures temperatures up to +650°C. Measuring even higher temperatures beyond +650°C would mean shifting to an even lower-sensitivity mode (a so-called third gain mode), where higher temperatures can be measured at the expense of image detail and contrast, leading to unacceptable image quality loss. A third gain mode might prevent firefighters from seeing victims, colleagues or escape routes, which is a serious safety and rescue issue.
2. Predicting melting steel structures?
Thermal imaging cameras are sometimes said to be able to predict when steel will start to melt and bend. This could especially be useful in firefighting scenes with industrial buildings which often have a steel framework. However, this would still be very difficult, even with thermal imaging cameras that can measure up to +1,100°C since the melting point of steel actually is a lot higher (around +1,400°C ).
Will my FLIR TIC survive higher temperatures?
K-Series TICs are designed to withstand the toughest firefighting conditions. They can take a 2-meter drop onto a concrete floor, are water resistant (IP67), and remain fully operational up to +260°C for a five-minute duration. The K65 complies fully with the NFPA 1801:2018 standard for firefighting thermal imaging cameras.
For more information, go to www.flir.com.au/instruments/firefighting/