Understanding Temperature Modes:
Firefighters need to understand that as temperatures increase within the Thermal Imager’s field of view it will eventually switch from high sensitivity to low sensitivity. It is important to note the following:
• Why the TIC does this?
• At what temperature and pixel count does this occur?
• How does this affect image clarity and decision making?
To gain a better understanding of this subject, please read the following article that we published in Gulf Fire Magazine:
gulffire.mdmpublishing.com/th...
Why does the TIC do this?
In order to “see” these temperature ranges effectively, manufacturers break up the temperature ranges into spans or temperature ranges. The majority of dual temperature mode fire service TIC’s break the temperature range down into the following:
• High Sensitivity: Zero-300 degrees Fahrenheit* (some switch at 200, 230, or 270 Degrees)
• Low Sensitivity: 300-1200 degrees Fahrenheit
As we can see, the second range is the Low Sensitivity Range which is defined by NFPA 1801 as: “The least thermally sensitive operational mode, used to increase the thermal imager’s temperature range” NFPA 1801 Section 3.3.24.1
To clarify this statement further, many fire service TIC’s when they switch to Low Sensitivity Mode loses discernible details in the lower areas below the thermal layer.
Important Note:
Firefighter’s need to be aware that their focal point or perspective will determine their level of severity. For example, a firefighter can be in a thermally severe environment (such as high heat conditions nearing rapid fire development) and have the TIC in high sensitivity mode by pointing it at the floor or away from the heat. And if their TIC has a low Distance to Spot Ratio (or a high pixel count requirement for the TIC to switch modes) they will NOT detect dangerous levels of heat until they are too close for comfort.
In other words, firefighters need to know more than just how to turn the thermal imaging camera on. There is so much more to thermal Imaging for the fire service, yet we barely scratch the surface in our training or in this article. Our goal is to inspire others to become intelligently aggressive and use this technology to their advantage. Notice in the following photos the differences between High & Low Sensitivity in regarding discernible details or image clarity in high heat environments. The following video will is our explanation of this concept. We are demonstrating it with the FLIR KXX series TIC switching from High to Low Sensitivity Mode. It is important to note that Low Sensitivity mode is indicated by the green triangle in the upper left hand corner in newer models of TICs.