It Wasn’t That Hot?
This is the most common statement we hear from firefighters before conditions suddenly changed without warning.
Or was there a warning?
What is the problem with our subjective measurement of heat?
What does the victim think about our “measurement of heat” while they are wearing pajamas while we are over-insulated in the best PPE ever made?
What is also a common statement mentioned in NIOSH LODD reports?
“Reading Fire Behavior Indicators & Recognizing Fire Conditions Serve as the Basis for predicting likely and potential fire behavior”
In other words, we failed to recognize changing fire conditions and were unable to predict the pending rapid fire development that occurred.
Why?
We offer the following reasons:
* 50% of the time the Thermal Imaging Camera is left on the charger of the fire truck.
* Firefighter PPE is built to such a high standard and firefighters wait until they feel pain before mitigating the thermal threat. At this point, it is far too late.
* TIC Misinterpretation: Firefighters who carry the TIC fail to properly interpret the image. Common mistakes that are made are as follows: Firefighters read the spot temperature instead of interpreting the entire scene. Firefighters fail to recognize gray scale (hot moving convection currents) as a threat. And in many cases, certain models of thermal imaging cameras fail to show colorization until 500 or even 1000 degrees Fahrenheit!
We have had more firefighters fail to interpret the image correctly due to a lack of training and they don’t properly interpret gray scale. As shown in the video, by using a different application mode (such as Search & Rescue Mode in the FLIR K55) it shows colorization beginning at 200 degrees Fahrenheit instead of 302 degrees Fahrenheit.
Many would argue against early colorization but they have failed to take into account the following:
* Firefighters have seconds to scan and interpret an image. If they misinterpret the thermal data they could be unaware of the impending rapid fire development.
To assist with combating this problem, NFPA 1801 (in the new 2021 standard) has removed the spot temperature from the initial start-up application mode known as TI-Basic. However, NFPA still allows manufacturers when to engage colorization. We offer the following examples of various models to demonstrate how this issue has made interpreting the thermal image more complicated.
MSA 6000: This model shows colorization in High & Low Sensitivity beginning at 270 Degrees Fahrenheit in High Sensitivity but doesn’t show colorization until 1000 degrees Fahrenheit in Low Sensitivity.
Drager UCF 9000: This model shows colorization in both High & Low Sensitivity. It complicates matters by showing red at 270 degrees Fahrenheit in High Sensitivity but then showing red at 1500 degrees in Low Sensitivity.
Scott X380: This model has Tri-mode sensitivity which shows color/temperature correlations in three separate modes. High Sensitivity begins showing colorization at 300 Degrees Fahrenheit. Medium Sensitivity begins showing colorization at 400 degrees Fahrenheit. And Low Sensitivity begins showing colorization at 600 degrees Fahrenheit.
Bullard QXT/NXT: This model simplifies color/temperature colorization by only showing colorization in Low Sensitivity but fails to show colorization until 500 degrees Fahrenheit.
Argus MI-TIC series: This model has Tri-Mode sensitivity consisting of High, Low, and Extended Low Sensitivity but simplifies interpretation by not changing the color scale as the TIC adjusts to the amount of heat within the field of view. It begins showing colorization at 392 degrees Fahrenheit.
Leader: This model has Tri-mode sensitivity consisting of High, Low, and Extended Low Sensitivity but simplifies interpretation by not changing the color scale as the TIC adjusts to the amount of heat within the field of view. It begins showing colorization at 392 degrees Fahrenheit.
FLIR K33-K65: This model simplifies color/temperature colorization by only showing colorization in Low Sensitivity and it shows it early at 302 degrees Fahrenheit. As demonstrated in the video, this model initially displays the image in TI Basic and the firefighters see no colorization whereas when switched to Search & Rescue Mode (which is a single gain mode the begins showing color at 200 degrees Fahrenheit) firefighters can quickly identify areas that would have been normally missed.
We hope that this general overview decision making TIC’s currently on the market has “sparked” your interest to learn more. As each TIC varies in its color/temperature association, required pixel count to switch from High to Low Sensitivity, Distance to Spot Ratio and more.
Therefore, if your department is using various models and different brands simultaneously, this could be a recipe for failure. Firefighters need to have an easy to understand color palette, high resolution, and colorization that engages early to provide an early warning of the conditions around them.
Stay Intelligently Aggressive.
Instructor Andy Starnes
Insight Training LLC
Level II Thermography Certified
