Temperature-How do we as firefighters measure heat?
Thermal Protective Performance- TPP is what defines the thermal insulation of structural firefighter protective clothing. The test result is based on the predicted elapsed time that will occur before an average individual will sustain a second-degree burn (130 degrees). The actual TPP rating is this time multiplied by the energy level of the test exposure. In this case, the exposure level is at 2.0 calories per square centimeter per second. This represents the amount of heat energy that a firefighter would face while being in the same room during a flashover or backdraft. Thus, the minimum TPP rating of 35 is 2.0 cal/cm2-sec times 17.5 seconds. The 17.5 seconds is the time that a firefighter would have to escape from the environment under that exposure condition before sustaining second-degree burns.
Thermography-The study of remote temperature measurement. How is this done? How effective is it? E.G. How does a TIC work?
The Human Thermometer: Understanding Temperature, TPP, and Thermography all lead up to this: Temperature is a measurement of heat. How do firefighters measure heat? By their ears, their contact points, the air in their bottle? Once our TPP is maxed out and our gear is saturated our skin is 130 degrees. At 140 degrees, our skin goes numb. There goes our thermometer. At 162 degrees our skin is destroyed. Wait, we hadn’t got to 212 yet to steam the victim? See where this is going?
Recognizing Fire Behavior Phenomenon’s: Incipient Stage Fires: The tips of flames are between 600-800 degrees but the room temperature may be significantly less dependent upon fuel, geometry/configuration of the rooms/fuels, and ventilation.
Growth Stage Fires:500-800F Fully Developed/Flashover: 900 and above. The ignition temperature of CO is 1128 F
Decay:1000 and below. Flow Path: the movement of heat and smoke from the higher air pressure within the fire area to all other lower air pressure areas both inside and outside of a fire building. Neutral Plane: The point in a flow path where the pressures are neutral (between the intake and exhaust). This is an indicator of fire growth based upon its height which is easier to identify via a TIC
Thermal Cues: Signs of heat indicative of a possible problem/fire that deems worthy of investigating.
Key Attributes of Thermal Imaging: Field of View: Modes (Temperature/Function) Colorization of Palette Resolution Distance to Spot Ratio Emissivity Language of the TIC: Mode Indicator Overheat Indicator Relative Color Bar Focal Point (DTM)-Direct Temperature Measurement
Contraindications of TIC: False Positives: Reflections Blocked Optic Lens Intrinsically Safe? Incorrect Interpretation-Scanning too fast, reading the spot temp instead of the palate. Over-temperature Failure
Exterior offensive attack followed by an aggressive interior offensive extinguishment. The fire service uses the term "transitional attack" which is similar to this video. The difference is the opening of the single intake to increase the air intake and then ensuring the solution (stream is applied into the air intake only (under-pressure).
Here is a video conducted in KTF 2011 led by Khris Garcia using Positive Pressure Attack. This tactic is very effective in eliminating flashover conditions in access path of the fire suppression crew. At the end of the video you will see Kriss standing at the doorway of the fire room and the temperature of his harness of the SCBA harness is 6 degrees hotter than the outside air (66 degrees).
This video shows the exterior thermal imaging video as seen from the ISG E-380 thermal imager during Kill the Flashover 2013 Burn 19-2. This fire attack was a traditional fire attack using an 1 3/4" attack line flowing 40 gpm of 0.40% Novacool solution. A total of 7 gallons of foam solution was utilized to control the fire. The fog stream was moved aggressively around the fire room which allowed the fuels to be quickly cooled, reducing the thermal insult to the firefighters. The interior thermal imaging video can be found on the KillTheFlashoverProject YouTube page. As time progresses we will be posting numerous angles from this burn as we had 19 cameras recording on each burn we conducted during Kill the Flashover 2013.
Here is the interior thermal imaging video as seen from the ISG E-380 thermal imager during Kill the Flashover 2013. This fire attack was a traditional fire attack using an 1 3/4" attack line flowing 40 gpm of 0.40% Novacool solution. Observe the aggressive nature of the nozzleman. The fog stream being moved aggressively around the fire room allowed the fuels to be quickly cooled reducing the thermal insult to the firefighters.
This is a quad screen showing two ISG E-380 thermal imagers and one CCD camera . The video shows the interior conditions while crews place a curtain on the exterior door opening and then make entry into the fire area. The fire attack was a Novacool wetting agent solution attack with a maximum flow of approximately 20 gpm. The total amount of solution flowed to control the fire was less than 10 gallons of solution.
This video demonstrates the use of the door to control the air intake to reduce thermal insult to fire personnel and better control the fire. When you watch this video observe the area inside the door and above the attack position. The fire attack was done with a low expansion foam tube flowing 20 gpm of 0.40% Novacool solution through a 1" attack line. When the door is open the fire continues to grow as the amount of air flowing into the room allows the fire to overcome the 20 gpm Novacool solution stream. The thermal insult to the firefighter is great during this attempt to control the fire. When the door is totally closed there is no visible fire in the attic area. The lack of an air intake greatly slows the fire spread in the attic. When the door is cracked the fire in the attic becomes visible and grows.
The nozzle is placed into the opening of the cracked door flowing towards the bottom of the room. The fire attack with the door cracked allows the 20 gpm Novacool solution stream to overcome the fire and nearly eliminate the thermal insult to the firefighter.
This is the thermal imaging video of the fourth burn of Kill The Flashover 2012. This burn is the same burn as featured inhttp://youtu.be/d037juQs6Vc as seen from an ISG E380 thermal imager. The fire attack was done using 0.40% Novacool solution into the under pressure area of the fire window. The line was flowed into the under pressure as an exterior offensive fire attack and then stopped. The attack crew then moved to the interior to extinguish the fire.
This video was shot during a recent training burn at the Albemarle, NC Fire Department. The footage was obtained using a hand held ISG XR Thermal Imager. The fire attack was a traditional fire attack advancing from the unburned side to the seat of the fire. This video clearly demonstrates the amount of heat the fire attack crew is exposed to while conducting a traditional offensive fire attack.
Here is a traditional fire attack as seen through an ISG XR thermal imager. This video was recorded during a recent training burn at the Albemarle, NC Fire Department. The fire attack was done with no instuction given to the attack crew other than to put out the fire. Compare the amount of exposure attack personnel take in the traditional fire attack in relation to the transitional fire attack.
These videos were taken as the house utilized for training was allowed to burn. The videos are played in progressive order. The clock on the video will show the amount of time that lapsed throughout the video. The videos were taken using an ISG XR thermal imager.