KTF Society.. Why is temperature of 500 degrees F so important to the firefight? Our best fire gear begins to char at 572 degrees F; our communications begins to fail less than 300 degrees F. Our face piece fails at approximately 400 degrees F Note 3. These failures occur from the impact of heat flux not necessarily ambient temperatures. Most US firefighters do not have an understanding of heat flux Heat flux measurement is expensive to detect and record and not easy to measure. [insert] Figure 1 https://definedterm.com/radiant_heat_flux Temperature and heat flux are only correlative to a certain context. Temperature is easy to measure (albeit not always correctly measured). Thus we communicate in temperatures. Fire growth is tremendously expansive after 500 degrees F. In other words, it takes minutes for a fire to grow to 500 degrees F, though it will go from 500 degrees F to Flashover in seconds. [IInsert]
Figure 2 http://www.thefreedictionary.com/flashover A firefighter’s Gear (PPE) will not tolerate flashover conditions without serious injuries or death. The key to stopping a rapid fire event or growth is stopping flaming. Flame is the reason for extreme growth [insert]
[insert] Figure 4
Here are a few equipment failure facts that you may find interesting: •SCBA Composite Bottles 1700 degrees Fahrenheit for 10 seconds and still function. •SCBA Face piece: 446 degrees Fahrenheit Polycarbonate Melts (Fails at 20 kW/m2 heat flux). "SCBA lens's exterior surface temperature reached 280 degrees Celsius (536 degrees Fahrenheit), about the midpoint of the range of published polycarbonate melt temperatures. The lens developed a significant hole, according to the NIST report." (A Mensch, G Braga and N Bryner, Fire Exposures of Fire Fighter Self-Contained Breathing Apparatus Face piece Lenses. NIST Technical Note 1724, Nov. 2011. The report can be accessed atwww.nist.gov/manuscript-publication-search.cfm?pub_id=909917.) •Firefighter Radios- The failures occurred while the radios were subjected to a temperature of 160 degrees Celsius (320 degrees Fahrenheit), termed Thermal Class II conditions.** The temperature is representative of a fully involved fire or conditions outside a room when its contents burst into flames simultaneously, a phenomenon known as flashover. NIST Technical Note 1474http://fire.nist.gov/bfrlpubs/fire06/PDF/f06001.pdf From Andy Starnes FB Post 061917 on Tactical Thermal Imaging, for more contact Andy Starnes at KTF Without flaming or an active air track we rarely see temperatures above 500 degrees F in the smoke storage area (Plug) without an active air track in the smoke storage area. This makes the environment within our specifications of our PPE (Personal Protective Equipment) and lowers our thermal risk significantly. [insert]
The previous Figure 1 depicts the important variables in the KTF Fire Suppression Theory. Most US firefighters do not understand that the Fire Triangle is also a fire suppression theory. KTF’s theory is additional learning from the fire triangle. The KTF Theory is more focused on the fire suppression of High Release Rate fuels in vent limited conditions. This context best represents what our crews encounter in most fire responses. Theory of Fire
Very little is known in the US fire Service about anti-ventilation fire behavior sciences. The US service has been in the surface cooling arena for 60 years, not many classes taught Gas Cooling or its sciences in the last 6 decades prior. Often the classes that were taught were mis-leading and often not correct. Ventilation and Anti-Ventilation Links: http://cfbt-us.com/wordpress/?tag=anti-ventilation&paged=2 http://www.firerescuemagazine.com/articles/print/volume-9/issue-4/strategy-and-tactics/anti-ventilation-tactics-on-the-fireground.html The service moved its focus to teaching engine and truck company operations with only 1 theory of extinguishment for all fire attacks. The method was developed in the 50’s and 60’s and was a technique used for low release rate fuels which utilized vertical over the fire ventilation to release low over pressure gases and low megawatt heat (compared to today’s rate). These tactics have been optimized to deal with the exceptions or fatal over the years. (not so well) Unfortunately the fire loads gradually1 changed to high release rate fuels, mostly hydrocarbon based fuels with high megawatt heat capability. One overstuff chair is equivalent to a 5 gallon can of gasoline which can produce the amount of heat and fuels to produce a flashover in an average size house room in 4 minutes or less compared to a legacy age fire load of 30 minutes on average. Legacy vs. Modern home furnishing fire: https://www.youtube.com/watch?v=IEOmSN2LRq0 Flashover: https://www.youtube.com/watch?v=BtMmymOxdjc KTF Fire Suppression theory includes the KTF 6 functions of Fire Suppression
Each Function carries with it a set of skills and science understanding. For instance in function 4, to access a fire compartment the TIC provides critical information to the crew prior to advancing into a room or compartment attempting to make access to the target fire compartment. (Taken from Facebook, (Tactical Thermal Imaging), Andy Starnes. https://www.facebook.com/permalink.php?story_fbid=1733669096932045&id=1431857577113200¬if_t=like¬if_id=1497923836510282 “In KTF we advocate a Go/No Go Decision Model for making entry, moving from compartment to compartment (room to room), and we use the TIC as a part of this model to assist in our decision making. https://youtu.be/vgWNXMts9d4 In this example we can clearly see the neutral plane collapsing, the environment ahead is over 500 degrees, and we have turbulent gases moving over our head. These are all indicators of a No-Go. We must mitigate these factors before moving forward to keep the environment tenable for firefighters and to prevent rapid fire progression. In this video, pay close attention to when the mode changes from Medium to Low Sensitivity the overall color palette changes to mostly gray scale even though the temperatures increase. Many firefighters would be fooled into believing that this environment is safe when it is actually worse. We must be diligent in learning fire behavior, the cues and clues that are indicative of those changes, and how to interpret this data thermally through our Thermal Imaging Camera.” https://www.facebook.com/45892463260/videos/10154804822153261/ Here is a video of a crew doing a tactical 360 and making access to a concealed fire using the KTF RISK Model: https://www.facebook.com/45892463260/videos/10154783205053261/ [insert] Figure 7
Unknown Life Risk is a situation of completing a primary and secondary search of a structure that the life risk is not known or highly probable.
Highly Probable Life Risk is a situation where the information is highly probable that a person is in the IDLH area of the structure.
Savable Life Risk is a situation where the information of occupancy is credible. The Risk Model percentile is a statistical calculation of successful completion of tactical behaviors on previous fire ground responses.
In very simple terms, we as a service have the ability to manage temperatures in a vent limited type fire. KTF will continue strive to create a manageable fire suppression environment that will not burn or kill the fire crew accessing a fire room. If our tactic grows the fire, even at the beginning, the tactic should be questioned. A tactic that creates a short window of opportunity should be a last resort choice. The risk to the crew once the window of opportunity ceases, is at a very high cost (lives).
[insert] Figure 8 Control the Air for combustion. Velocity of gases is the key (correlative) to fire growth. The Curtain plugs the movement of gases thus greatly reducing fire growth. That is why controlling the door is so important. Door control ties up one firefighter for this task, as opposed to using a smoke block-aid curtain which works automatically. A door left open is over 21 square feet of intake and exhaust opening as compared to a 4 x 4 roof opening that is 16 square feet. The outside opening’s location is important to the location of the active flaming (combustion). A lower pressure point is usually associated with the lowest elevation of an opening unless the fire’s neutral zone has dropped to the lowest intake hole. We say at KTF, firefighters are afraid of the dark. The reason we say this is that most firefighters are not comfortable closing the door behind them. The Thermal Image Camera allows the firefighter to discern the layout of the compartment/s without optical visual sight. Streams provide cooling on the static smoke (gases) contracting the gases providing lift in the space. Stopping the movement of the confected heat currents slows the fire growth tremendously.. This contraction of gases along with the thermal capabilities of the TIC provides an opportunity to clear the space of a life hazards as the cooling and control of the space is achieved.
Air control is the variable that limits the fire growth and thus limits the amount of water it takes to control the temperatures.
[insert] Figure 9
If the fire can’t breathe in new air, it cannot grow. If it cannot grow, it takes less water to extinguish. The picture above the firefighter is using a “Fog Nail” using about 17 to 20 gallons per minute. How does this small amount of water put out the flames in this attic? Most of the water of the 17 to 20 GPM is converted to steam and it is not vented outside (note: steam is invisible). Steam and flame can’t exist in the same space. With the reduction of oxygen and the steam traveling into the flaming area of the combustion, the flaming ceases! Now the firefighter must stop smoldering combustion with surface cooling without adding additional air (oxygen) . Heat (temperature is reduced) and flaming cannot be sustained.
Now add the thermal data leg of the KTF fire 3 legged Stoll and we use the TIC to determine if we have hot spots that need to be surface cooled. This process does not add additional air and we extinguish the combustion and then restore the environment. KTF’s version of the use of the TIC is referred to as Tactical TIC.
“Why is Tactical TIC Use Important to Firefighters? By Andrew Starnes Since the late 90’s many fire departments have been using thermal imaging cameras: so what is “tactical thermal imaging” all about & why is it important? By definition the word tactical means: “relating to a maneuver or plan of action designed to quickly gaining a desired end or temporary advantage” (Merriam Webster). Tactical thermal imaging can be compared to a paradigm shift or a change in the way we view the fire ground. It is the knowledge, skills, and training we already have and then enhancing them by adding another perspective: the thermal perspective. Many incidents that firefighters encounter could be enhanced, made more efficient, and perhaps prevent the loss of lives by using this added perspective. Thus, Tactical Thermal Imaging can be defined as the usage of a TIC to better diagnose the IDLH environment we are in for the purposes of strategic decision making. Why is this training necessary? As the overall fire environment has changed, the fire service has responded by improving firefighters gear with higher thermal protective performance thereby shielding them from thermal insult longer creating an illusion of superiority in a rapidly progressing thermal environment. Many firefighters are not aware of the amount of heat they are being subjected to and how close they are coming to actual injury. In their research to evaluate the temperatures that firefighters are exposed to and their equipment, Donnelly states: “The advent of the new equipment and technology has greatly improved the personal protective gear worn by firefighters. The disadvantage to this is that firefighters are now able to enter more dangerous conditions than they previously did and this can mean more risks and dangers to the firefighters. Firefighters may be relying more heavily on their technology to warn them of dangers they cannot “feel” and to safeguard them in the event of an emergency. The equipment may be subjected to more dangerous conditions than in the past and a heavier reliance on the equipment calls for a better understanding of its limits”(NIST Technical Note 1474, p. 5) (photo courtesy of Globe). In many instances firefighter’s aren’t aware of what the thermal protective performance (TPP) of their PPE is and how well they are protected. The fire service has provided some of the best PPE & equipment to date for firefighters but they must be aware of its limitations. So How Do Firefighters Measure Heat? Today’s thermal environment of higher heat release fuels demands a diagnostic tool that allows firefighters to prevent thermal insult, identify & locate the fire’s severity, and locate any victims or firefighters in danger more quickly than ever before. And those who still advocate that firefighters should wait to feel the heat to indicate their level of safety should read and remember the following: The equipment we use to protect ourselves or work in these superheated environments are designed to operate at only a Thermal Class III for a maximum of five minutes which equates to 500 degrees or less of moving heat convective currents before our PPE and equipment begins to fail. Researchers and product developers have divided the environments that firefighters operate into four thermal classes which are shown in the above infographic. It is important to note how long we can operate in these temperatures Figure 10 without our PPE & equipment failing. In addition to this data: Most fuels, or contents, begin off-gassing between 300-930 degrees Fahrenheit. Carbon Monoxide ignites at approximately 1100 degrees Fahrenheit. The Polycarbonate of a SCBA Mask begins to fail at 446 degrees Fahrenheit (it begins to soften at 300 degrees Fahrenheit). And Firefighter PPE (Turn-out gear) begins to fail 572 degrees Fahrenheit. The Minimum Thermal Protective Performance of turn-out gear (PPE) provides 17.5 seconds of protection before a firefighter receives a second degree burn in flashover temperatures. This is rating is for brand new PPE. In addition to this, the human body receives a second degree burn at 130 degrees Fahrenheit and at 140 degrees Fahrenheit; the human body’s pain receptors “are turned off” thereby preventing firefighters from feeling any pain or heat at above this temperature. How then are firefighters recognizing the true thermal severity of these events without a diagnostic tool such as a thermal imaging camera? Therefore, inherent problem with our training is that we rely on visible cues or “feeling” to recognize rapid fire progression in an environment with limited visibility and very little sensory ability. These fire behavior phenomenons shown in the photo above are taught to firefighters in classrooms or in burn buildings where the environment is well ventilated and controlled in order for the student to visibly see these conditions. Yet when firefighters actually face these conditions, they are often in near zero visibility and often fail to recognize the indicators of rapid fire progression until it is too late. Therefore there has never been a greater need for firefighters to be trained in understanding fire behavior, thermal severity, and how to interpret this data through tactical thermal imaging.” Author is Andy Starnes
IF we use all 3 legs of the KTF Fire Suppression bar stoll we enhance our ability to suppress large fires and protect our crews from thermal injuries. Enhanced Water Streams delivered effectively (directed by a thermal Imager) provide the crew and the customer with thermal protection beyond any capability we have demonstrated in the history of the fire service.
An Enhanced Water Stream improves surface cooling capabilities several times that of a non-treated water stream. This science is more than a vapor barrier science that is the most commonly used in foam training science with class B fuels today.
Moisture and flaming do not exist in the same spot in ambient air oxygen content. An untreated water droplet molecule has greater rigidity and will maintain its shape and rigidness. The droplet is more affected by gravity and will not deposit water effectively on a surface as it travels due to slope and gravity.
The small amount of treated water in the 2 Liter container photo will control more heat and for a longer period of time than an equal amount of non-treated water. [insert] Figure 11
KTF tests consistently and easily demonstrate almost 4 times the coverage and staying power of enhanced water vs unenhanced water. Every delivered gallon of enhanced water appears as a 4 gallon equivalent of non-treated water.
Moisture does the work when delivering Enhanced Water Stream, not the agent. The agent enables the water to stay and do the work.
KTF advocates conditioning (wetting with EWS) surfaces of materials to increase the moisture of the exposed materials thereby slowing the speed of the fire growth in the affected area. Here are two tests comparing water with enhanced water: Regular Water: https://www.youtube.com/watch?v=5tdaeqo3-mE&t=11s Enhanced Water https://www.youtube.com/watch?v=RcXn_tK56Xw To support a fire growth condition, the fire must remove the moisture to enable rapid fire growth. As you can see the enhanced water hangs out much longer than regular water. This gives the fire crew a longer window of opportunity to suppress the fire and prevent a rapid fire event such as flashover or backdraft. Water that stays- works: https://www.youtube.com/watch?v=sHZKESmY914
Why are streams directed into the upper thermals first? UL encourages the fire crew to place the stream in the ceiling and rain it down on the fire. This will kill the fire growth with enough water (GPM). It is Not the most efficient use of the moisture. The Gas or Vapor space is a replenished fuel space from the burning contents of the room (which in a residential structure is mostly 48 inches and down in the living space. Most firefighters do not have an understanding of contraction and under-pressure vapor movements.
Wind speeds above 4 MPH influence fire pressures, thus speed of fire growth.
[insert] Figure 12 The air track is a result of the phase of the fire, context (LxWxH) or (Cubic feet) of the fire , fuel of the fire, available outside air and outside pressure (wind) and phase change of the fire growth. Notice the high window on the Delta side. As the neutral zone passes below this window and if the window is a single pane glass; any flaming at the NZ passes will break this glass and cause a bi directional flow to develop at this level which will result in active flaming at this level. Fire growth will exponentially increase. So you can see that there are many variables that can influence fire growth. The main point to remember is that high release rate fuels need tremendous amount of air to reach the heat potential of the fuels. Control the air and you can control the fire growth.
The flaming of a fire is the piece of the phases of fire that cause the extreme or high growth of temperatures. Fully developed phases of fire require a two part extinguishment, 1st: stop the flaming, 2nd: surface cool the smoldering combustion areas to fully extinguish the fire in that order. Moisture is the kryptonite to flaming. Again the 3 principles of Modern Fire Attack are: ·Always know the Temperature ·Moisture goes First ·Always Dampen the Air intake High release fuels generate an overabundance of fuel when off gassing begins. By overabundance, we mean that the product produces more fuel than the ambient available oxygen can support a fuel limited fire (combustion.) High release rate fuels need high velocity air movement to support the rapid fire growth seen in many fires. They require a turbo (symbolically) to supply the air needed to rapidly burn the fuel created. As the heat rises the pressure increases and the speed of the exhaust increases. The exhaust is liken to a person exhaling. The chest rises on the inhale which is liken to the fire temperature creating pressure to exhale. As the fire exhales, the lungs create a negative pressure to allow air to enter. If the fire cannot exhaust, it cannot intake enough air to support combustion.
Here are a few scenarios:
[insert] Figure 13
The first scenario is a room and contents fire with minimum staffing with a perpendicular wind source Upon arrival of the first Engine, 1. Engine arrives on the scene (staffing of 2 and 1 command buggy with 1 command officer) Assumption and confirmation of Command (Benchmark – Command Established 2.Tactical 360 with TIC is conducted by the Command officer. IC closes doors as the T360 is completed with a quick thermal evaluation. The fire is showing out the window of the Alpha Side with a 50% use of the window space used by the exhaust of an approximate 1000 square feet. The flaming is totally outside the room. The alarm was called in by a passerby and there are no automobiles in the driveway. There are no toys or bicycles in the front or rear. 3. Engineer sets up pump (1250/1000 pump and tank) as Tactical 360 is being completed. First attack line is deployed (1 “ 200 feet35 GPM Enhanced Water) by engine company officer. 4.The IC gives the size up with the IAP (remembering next in companies) and establishes a fixed position Command. 5.The Engine officer makes an under pressure attack into the window of the fire room knocking down the flaming in the room. (benchmark – Water on the Fire) 6.The 2nd Engine arrives on the scene and prepares to make entry into the structure for the primary. 7.E2’s crew hangs a smoke blocking curtain on the access door, advances a 1 ¾” line and 3 D’s the door prior to entry. 8.The 3rd Engine arrives on the Scene and goes on-deck with RIT responsibilities and 1 FF connects 2nd booster tank water to attack engine and takes engineer responsibilities for Engine 1 9.Engine 2’s crew conducts Go/ NO Go and controls temperatures upon entry. Their responsibility is to isolate the fire from the remainder of the house and drop internal thermals under 150 degrees F with contraction sciences. 10.Engine 1 advances line into the structure to extinguish the fire. 11.Engine 2 completes the primary. (benchmark - all Clear) 12.Rescue arrives and establishes Refresh and Rehab. (conditional – no victim) 13.Remaining fire ground responsibilities not noted here.
Insight Training LLC & Project Kill The Flashover Introduction to Tactical Thermal Imaging
Instructor Andy Starnes:
Andy is a lifelong student of the fire service and has been involved with the fire service as a volunteer since 1992 and as a career firefighter since 1998. He is a fire service website contributor on the topics of thermal imaging, fire behavior, leadership, behavioral health, and faith based devotions. He also is the founder of www.bringingbackbrotherhood.org,, a nonprofit organization designed to encourage and provide guidance for firefighters in the area of behavioral health, counseling, and more. Andy is passionate about Fire Behavior and assisting in instructing others on understanding the complex terminology of modern fire behavior on a regular basis. He has been featured on the Firefighter Training Podcast, moderfirebehavior.com, and presented tactical thermal imaging courses at internationally, in 28 states, and at numerous fire service conferences across the U.S. He currently serves as a Captain on an Engine Company in a large career department in NC, as the Deputy Chief for KTF Burns Division, and a Thermal Imaging Subject Matter Expert (Level I Thermography Certified) consulting & teaching in the areas of Tactical Thermal Imaging. He is a certified NC Fire Officer III and has a Bachelor’s Degree in Fire Science Administration. @KTFBurnsDC Instructor
Andy Starnes 704-507-7156 Insight Training
Table of Contents I. Introduction-Before We Apply, We Need to Know Why! II. Understanding Your Thermal Imager III. Five Key Attributes of Thermal Imaging IV. Application-Tactical 360 V. Go/No-Go Decision Making VI. Enhanced Stream Placement VII. Enhanced Search Methodology VIII. Fire Station Training & Implementation IX. Thermal Imaging Needs Assessment/Purchasing Guidelines X. Thermal Imaging Definitions-A to Z
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Insight Training LLC
Project Kill The Flashover
5 I. Introduction
Since the late 1990’s many fire departments have been using thermal imaging cameras across the world; but what is “tactical thermal imaging” all about? Why is it important to firefighters? By definition the word tactical means: “relating to a maneuver or plan of action designed to quickly gain a desired end or temporary advantage” (Merriam Webster). Tactical thermal imaging can be compared to a paradigm shift or a change in the way we view the fire ground. Therefore, it’s the knowledge, skills, and training we already have thereby enhanced by adding an unseen perspective by the human eye: the thermal perspective. Many incidents that firefighters encounter can be enhanced, made more efficient, and perhaps prevent the loss of lives by using this added perspective with proper training. Thus, Tactical Thermal Imaging can be defined as the usage of a TIC to better diagnose the IDLH environment we are in for the purposes of improved strategic decision making. Insight Training LLC Project Kill The Flashover 6 But why is it necessary? As the overall fire environment has changed due to modern construction and high heat release rate fuels, the fire service has responded by improving firefighters gear with higher thermal protective performance thereby shielding them from thermal insult longer. This often creates an illusion of superiority in a rapidly progressing thermal environment with simultaneous sensory deprivation. Many firefighters are not aware of the amount of heat they are being subjected to and how close they are coming to actual injury. In research to evaluate the temperatures that firefighters are exposed to and their equipment, Donnelly stated: “The advent of the new equipment and technology has greatly improved the personal protective gear worn by firefighters. The disadvantage to this is that firefighters are now able to enter more dangerous conditions than they previously did and this can mean more risks and dangers to the firefighters. Firefighters may be relying more heavily on their technology to warn them of dangers they cannot “feel” and to safeguard them in the event of an emergency.
Insight Training LLC Project Kill The Flashover
The equipment may be subjected to more dangerous conditions than in the past and a heavier reliance on the equipment calls for a better understanding of its limits” (NIST Technical Note 1474, p. 5) (photo courtesy of Globe). This leads us to yet another educational void in the fire service which is the failure to understand the limitations of a firefighters P.P.E. In many instances firefighters aren’t aware of what the thermal protective performance (TPP) of their Personal Protective Equipment (P.P.E) are and how well they are protected. The fire service has provided some of the best P.P.E & equipment to date for firefighters but they must be aware of its limitations. Each piece of personal protective equipment has to be tested in regard to the environment that it will function in. Each piece has its defined parameters, limitations, and known failure rates that are often overlooked nor understood in regard to temperature, duration of exposure, and heat flux. (Heat flux examples and definition are provided by the infographic by NIST FIRE) Insight Training LLC Project Kill The Flashover 8 In regard to firefighter training, very little applicable information is taught in regard to TPP, THL, thermal classifications, and how high heat release rates combined with heat flux limit the amount of time that firefighters actually are protected. The fact that each piece of equipment is designed to perform under certain temperatures for a certain duration isn’t considered in how long crews should remain inside for the attack effort. Depending on conditions, firefighting crews can saturate their gear with heat at lower temperatures and become burned after long exposures and have no signs of damage to their PPE whatsoever. So How Do Firefighters Measure Heat? Today’s thermal environment of higher heat release fuels and demands a diagnostic tool that allows firefighters to prevent thermal insult, identify & locate the fire’s severity, and locate any victims or firefighters that are in danger more quickly than ever before. And those who still advocate that firefighters should wait to feel the heat to indicate Insight Training LLC Project Kill The Flashover 9 their level of safety should read and remember the following: The equipment firefighters use to protect themselves or work in these super-heated environments are designed to operate at only a Thermal Class III for a maximum of five minutes which equates to 500 degrees or less of moving heat convective currents (of 10 kW/m2 of measured heat flux or less) before their PPE and equipment begins to fail. Researchers and product developers have divided the environments that firefighters operate into four thermal classes which are shown in the above infographic. It is important to note how long firefighters can operate in these temperatures without their PPE & equipment failing. In addition to this data: Most fuels, or contents, begin off-gassing between 300-930 degrees Fahrenheit. Carbon Monoxide ignites at approximately 1170 degrees Fahrenheit. The Poly carbonate of a SCBA Mask begins to fail at 446 degrees Fahrenheit (it begins to soften at 300 degrees Fahrenheit). And Firefighter PPE (Nomex Turnout gear & hoods) begins to char at 572 degrees Fahrenheit: PBI P.P.E fails at 1000 degrees Fahrenheit. Insight Training LLC Project Kill The Flashover 10 In basic firefighter training, there is little focus or time spent on understanding thermal severity. Firefighters are taught the life cycle of fire, the fire triangle and fire tetrahedron but often aren’t given an in-depth understanding of the power of heat, temperature, and heat flux. This text aims to provide firefighters with a better understanding of thermal severity and how it affects their performance & success or failure on the fire ground. The following quotes come directly from Fire & Emergency Manufacturers and Services Association (FEMSA) User Information Guide which comes with every brand-new set of Firefighter Protective Garments. The following information should be read and understood by all firefighters. • “If your protective ensemble is exposed to radiant, convective, or conductive heat, you may be burned underneath with no warning and no sign of damage to the protective ensemble. Be constantly alert to the possibility of exposure to radiant, convective, or conductive heat and other hazards” (FEMSA User Guide p. 2-4). • “Burns are a function of time and amount of heat transferred to the body. You can be burned in relatively low temperature environments. If your Insight Training LLC Project Kill The Flashover 11 protective ensemble is exposed to heat or flames long enough. Similarly, you can be burned over a very short period of time if your protective ensemble is exposed to relatively high temperatures” (FEMSA User Guide p. 2-4). Such as a Thermal Class II Environment of 320 degrees Fahrenheit for 15 minutes. • “Heat can build up and be stored in your protective ensemble element to the point that where your skin burns. Your skin burns at temperatures far below the burning point of your protective ensemble. Do not be misled by absence of thermal damage to your protective ensemble. Even without such damage, you may still be burned suddenly and without warning” (FEMSA User Guide p. 2-4). • “Convective Heat Burns: Convective heat is transferred by hot gases. You do not have to come into contact with flames in order to be burned. If your protective ensemble is exposed to heated air or gases at a fire scene you can be burned” (FEMSA User Guide p. 2-5). Notice in the photo, the thermal convective heat currents coming out of the room on the firefighter’s left. This can be compared to cooking in a Insight Training LLC Project Kill The Flashover 12 convection oven. A convection oven cooks food in ½ the time due to moving heated air. If firefighters fail to control the flow-path, fail to cool the superheated areas where they are going, then they are in effect crawling in a convection oven. There are numerous LODD reports where firefighters have died in uni-directional flow paths which are exhausts. These superheated gases overwhelm the firefighter’s PPE and in many LODD cases, firefighters did not have enough time to transmit a May-Day (see the San Francisco LODD report in the resource section). It is critical that firefighters understand and stop the transfer of heat, stop fire growth, and control the air to the fire (photo courtesy of Bullard). Insight Training LLC Project Kill The Flashover 13 The photo above shows the weakest link in a firefighters PPE (the face-piece lens). This material is made of polycarbonate, is 2-3 mm thick and begins to soften at 300 and failed completely at 500 degrees after 148 seconds in 15 kW/m2 heat fluxes (moving convective heat currents). This information comes from the NIST Technical Note 1785 Thermal Performance of Self- Contained Breathing Apparatus Face piece Lenses Exposed to Radiant Heat Flux (p. 10). Firefighters need to understand the importance in controlling temperature, mitigating/controlling flow path, and staying ever alert to changing conditions. Firefighters need to understand that the mask doesn’t just fail at 447 degrees but it begins long before that as the radiant heat flux begins to soften the material without any visual sign. Heat Flux-More Than Just Temperature! “Once the polycarbonate Reaches its glass transition temperature, it begins to lose all integrity and becomes vulnerable to physical impact.” NIST Technical Note 1724 Fire Exposures of Firefighter Self Contained Breathing Apparatus Face piece Lenses. P. 28 500 Degrees F @20 KW/m2 at 148 seconds Insight Training LLC Project Kill The Flashover 14 This includes live burn instructors (as shown in this adjacent photo courtesy of Insight Training LLC) who often stand up or stay in superheated environments for an extended period of time thereby shortening their PPE’s ability to withstand any rapid changes. In many cases, in training accidents, the live burn instructors are the first to be burned due to their gear being saturated with heat. Notice in the photo below by Bullard the firefighter is crawling near 1000 degree temperatures without injury. The firefighters PPE is absorbing heat at a rapid pace without any sensory alert until it’s too late. The Minimum Thermal Protective Performance of turn-out gear Insight Training LLC Project Kill The Flashover 15 (PPE), which is 35, provides 17.5 seconds of protection before a firefighter receives a second degree burn in flashover temperatures. This is the rating is for brand new PPE and in many departments the baseline TPP is an average of 40 which provides 20 seconds in flashover temperatures. “Even armed with this information, many firefighters have not considered the cumulative heating effect high heat has on their gear as they progress towards their objective. The built-in safety factor (or TPP) is often exhausted without any sign or recognition as firefighter’s crawl in superheated convective heat currents that gradually absorbs into their PPE. Then when a rapid-fire progression event occurs, firefighters do not have 17-20 seconds or more of protection due to their PPE being saturated with heat” (Euro Firefighter, p.339). In addition to this, the human body receives a second degree burn at 130 degrees (which occurs when the TPP of a firefighter’s PPE is saturated with heat) Fahrenheit and at 140 degrees Fahrenheit; the human body’s pain receptors “are turned off” thereby preventing firefighters from feeling any pain or heat at above this temperature (data courtesy of NIST Fire Research). This information comes from the “Stoll Curve” which is based on research performed by Alice Stoll in Navy Sailors volunteered to be burned on their forearm. “The Stoll Curve determines the rating of the transfer of heat Insight Training LLC Project Kill The Flashover 16 energy (calories) based on the time of transfer and the level of heat energy produced. Ideally, protective garments and equipment will delay the transfer by absorbing the heat energy at increased heat fluxes. Standards determine ratings as the amount of energy absorbed in cal/cm2 before the time of transfer to human tissue and the result of a predicted crossing of the Stoll Curve criteria (which, for short, standard writers and test houses call a “burn”). For example, per NFPA 2112: Standard on Flame-Resistant Garments for Protection of Industrial Personnel against Flash Fire, Section 7.1.1: Heat Transfer Performance, a garment is required to absorb 6.0 cal/cm2 of heat energy before the time to second degree burn in a ‘spaced’ exposure using the Thermal Protective Performance method” (Kirby, p.1). How then are firefighters recognizing the true thermal severity of these events without a diagnostic tool such as a thermal imaging camera? Therefore, the inherent problem with fire training is that we rely on visible cues or “our feeling” to recognize rapid fire progression in an environment with limited visbility and very little sensory ability. These fire behavior phenonmeon shown in the photo aboveare taught to firefighters in classrooms or in burn buildings where the environment is well ventilated and controlled in order for the student to visibly see these conditions. Yet when firefighters actually face these conditions, they are often in near zero visibility and often fail to recognize the indicators of rapid fire progression until it is too late. Therefore, there has never Insight Training LLC Project Kill The Flashover 17 been a greater need for firefighters to be trained in understanding fire behavior, thermal severity, and how to interpret this data through tactical thermal imaging. Understanding How A Thermal Imaging Camera Works: Before we address YOUR thermal imaging camera and how it can be used to enhance a firefighter’s strategies and tacitcs we must first understand how a thermal imaging camera works. Thermal Imagers work by reading heat signatures displaying contrasting temperatures upon a viewable screen based upon many factors. The camera then translates infrared waves into a radiometric signal which is translated into an image upon a screen for the end user to interpret. This occurs through five components: • Optic system-This is the lens or where the IR energy enters the TIC • Detector-This is also known as the FPA or Focal Plane Array. There are numerous detectors on the fire service market today but the most common are Amorphous Silicon (Asi), Vanadium Oxide (Vox), and Lepton (smaller than a dime, very inexpensive, and can fit inside a smart phone). • Amplifier-This amplifies the signal • Signal processing-This is the engine or speed of the processor. • Display: This is the viewfinder which is often a different resolution than the detector or FPA is. (schematic courtesy of NIST Technical Note 1499, p.18) Insight Training LLC Project Kill The Flashover 18 The TIC then interprets the data through 5 key attributes: • Field of View (FOV): This is the observable world through the vertical and horizontal view of the TIC. It is measured in degrees vertically and degrees horizontally and are often very narrow (averaging 37 x 50). • Distance to spot ratio: This is the distance that dictates the effective range that a TIC can measure a known parameter (or spot size). TIC Distance to Spot Size Ratio’s vary and are not typically consistent. • Modes & Color Palettes: A thermal imaging camera has temperature sensitivity modes and in some case application based modes. Every TIC will have at least a dual sensitivity temperature mode or a High and Low Sensitivity Mode. The Low Sensitivity Mode is indicated by a green triangle that is visible in the upper left-hand corner of the viewfinder and is typically indicative of at least 300 degrees Fahrenheit within the F.O.V. for the TIC to switch to low sensitivity mode. Application based modes are based on a specific use and typically have a special filter and dynamic range applied to each application based mode. • Resolution: Resolution is indicative of the total number of pixels that the detector or FPA has. In short, a TIC with a high number of pixels will produce a more detailed the image, a more accurate temperature measurement, and will be provide a more usable/discernable image at longer distances from the target. • Emissivity-This is the ability of an object to emit, absorb, or reflect Infrared Energy. Most Fire Service TIC’s are set at .95 Emissivity. The Optic System: The TIC receives an IR (infrared signal) through a Insight Training LLC Project Kill The Flashover 19 germanium metal lens. The optic system is what determines the TIC's Field of View, F.O.V, or its perspective. "Firefighters may need to utilize a thermal imager to maneuver within a burning structure. Therefore, a wide field of view is beneficial." [NIST Technical Note 1499, p.1] This can be compared to the eyes of the TIC. When you point a camera at a heat source the optic system picks up the heat and infrared radiation and starts the rendering process to the display. Optical System Factors: We need to be aware that our normal range of vision (Field of View) with our eyes can be up to 170 degrees but with a TIC it will vary between 37-55 (diagonally) degrees Field of View. We also need to be aware that the optic system is going to be very prone to getting covered up with smoke and soot which will affect the TIC's ability to accurately read the temperatures around us. As we work our way through the building and we wipe our face piece off we should take our gloved hand and wipe the optics off. Also consider, keeping the charging points clean after use will help to insure it charges properly. Optic System: Germanium Lens Infrared Energy enters through a 2 mm thick germanium metal window. This window can become covered with soot/debris/trash and can negatively impact the TIC’s ability to render a discernable image. The Optic System Insight Training LLC Project Kill The Flashover 20 “FOV is the largest area that a TIC can see at a set distance. It is listed numerically with the first number being the vertical view and the second number being the horizontal one. It can be compared to the windshield that a firefighter views the fire through.” It is not however, the size of the viewfinder or the screen size (Fluke Thermography, p.1). (photo Bullard T4 Max Courtesy of Insight Training LLC). The majority of the TIC's on the market today can be divided into two categories pertaining to Field of View (FOV) between 37 degrees and 50-55 degrees. The first number listed in the F.O.V. is the TIC’s vertical perspective or window and the second number is the horizontal dimensions. These numbers determine the windshield or area that a firefighter will be able to see through the device. Firefighters must understand that this diminishes our vision substantially. Insight Training LLC Project Kill The Flashover 21 The Detector (Sensor): This can be compared to the nose of the TIC. The detector is what detects the heat signal from the infrared radiation signal that the optic system is picking up. This is the most critical part of the camera. In general, there are two types of detectors: cooled and uncooled. Firefighting cameras are typically uncooled sensors because they require less maintenance and cost less. Once the detector picks up a heat signal it will send that signal on to the third part of the camera. It is vital for the user to understand the differences in the detectors in relation to their individual performance. “A micro bolometer is a specific type of bolometer used as a detector in a thermal imaging camera. Infrared radiation with wavelengths between 7.5-14 µm (or microns which is one millionth of a meter) strikes the detector material, heating it, and thus changing its electrical resistance. This resistance change is measured and processed into temperatures which can be used to create an image. Unlike other types of infrared detecting equipment, micro bolometers do not require cooling”. (www.wikipedia.com) *It’s important to note than the TIC only sees wavelengths within this range Insight Training LLC Project Kill The Flashover 22 There are four types of detectors that are commonly available: A) VoX technology (Vanadium Oxide): was first available in a military technology/use. B) ASi technology (Amorphous Silicon): is currently the predominant detector on the market due to availability and cost. C)Lepton technology: This is a relatively new detector to the fire service market. It is very inexpensive, smaller than a dime, and typically has a 160x120 resolution capability. C) BST technology-(found in older thermal imaging cameras and no longer in production) The two most common types of detectors on the fire service market are Vanadium Oxide and Amorphous Silicon. These two detectors are very similar in the way that they work but there are differences in their performance. Both detectors are very common on the market but ASi is increasing in its use due to availability. The Amplifier: The third part of the camera is the amplifier. This can be compared to the ears of the TIC. It takes the signal that has been received, detected, and it is strengthened. The signal amplifier takes the heat signal that optic system and detector picked up and amplifies it. Amplifying the signal Insight Training LLC Project Kill The Flashover 23 makes it easier the end user to be able to differentiate between certain heat signatures. Signal processing-: This can be compared to as the brain of the TIC. The fourth part of the camera is where the signal is processed before the end user sees the visual display. This is made-up of a small computer it takes the data it receives and turns it to the display for the end user. Different cameras on the market will process the data at different speeds, therefore a firefighter must understand this so their speed of movement doesn’t exceed the TIC’s capability to process and deliver the information. In addition to this, the thickness of the germanium window (which is part of the optic system) will vary which may allow the IR energy through faster or slow down the IR energy to the detector (the most common thickness is 2 mm). The human eye processes information at a rate of 27 Hz. One Hertz (Hz) is equal one frame per second. Therefore, never buy a thermal imaging “decision making camera” that operates at less than 30 Hz as it will be very slow to respond or lag. This will frustrate firefighters and cause them to miss valuable thermal cues. Insight Training LLC Project Kill The Flashover 24 For example, the most common processor speeds (frame rate/refresh rate) that are on the market today are: 9 Hz: This is a very common processor speed in low cost situational awareness thermal imaging cameras. 9 Hz is also a very common processor speed due to ITAR, otherwise known as the International Traffic in Arms Regulations and EARExport Administration Regulations laws. These laws or regulations restrict the export or use of thermal imaging cameras greater than 9 Hz due to the fact that thermal imaging cameras are first and foremost viewed as a military item. A TIC with a processor speed of 30 Hz or greater in the wrong hands could be used for harmful purposes thus there are many restrictions on these with faster processor speeds. Also, you will notice that many manufacturers offer 9 Hz processor speeds available for purchase because they can easily ship these internationally without the restrictions. 30 Hz: This is the minimum processor speed that a fire service TIC should have due to the human eye processes information at 27 Hz. 60 Hz: The majority of the high-resolution fire service TIC’s fall into this category. This is a very fast processor that works well with the fast changing environment that firefighters are facing today. Insight Training LLC Project Kill The Flashover 25 Display This can be described as the face of the thermal imaging camera. Our reactions are displayed upon our face and the ultimate picture that is translated through the processor of the TIC is ultimately displayed on the display screen of the TIC. The end part of the thermal imaging camera is the visual display. When you raise the camera up and look at the screen you are seeing a visual representation of infrared radiation on the screen. The size of the screen makes a difference in our ability to discern finite details. Smaller screens, even with higher solutions, can be a deficit to the end user due to the smaller objects may be even more difficult to recognize such as a small child's hand. However, it’s important to note that regardless of the screen size the greater the resolution the better the image quality. In addition to this, a firefighter should be able to hold the TIC at an arm’s length in smoke conditions and clearly see the display. If they cannot, the brightness level of the display is inadequate and should be calibrated. The user needs to be aware that image quality can make a significant difference in locating victims and reading the thermal environment correctly Insight Training LLC Project Kill The Flashover 26 II. Understanding Your Thermal Imaging Camera:Bullard Models: Bullard TIC’s: The Bullard T3, T4 & Eclipse Models operate very similarly, they share the same color palette, and are NOT intrinsically safe (which means they may be an ignition source in a flammable environment). Both are turned on via a power button located either on the front of the TIC below the screen at the Bullard T4, or on top of the Bullard Eclipse. The screen takes 4 seconds to power on and the user should always have a full battery before entering an IDLH environment. Both TIC’s may be equipped with two additional features: super red hot and Electronic Thermal Throttle (ETT). Super Red Hot-beginning at 500 degrees objects are colorized beginning with yellow, to orange, and progressing to red in color in the upper most temperature range. Electronic Thermal Throttle-The Thermal Throttle allows a firefighter in a NON-FIRE activity to identify hot spots during overhaul, locate overheated electrical equipment, to identify hazardous scenes, and can be used in size-up to assist identifying the location or severity of the fire but it is designed to be used in AMBIENT temperature situations. Insight Training LLC Project Kill The Flashover 27 Bullard T3, T4 & T4 Max Information: Bullard T3, T4 & T4 Max TIC’s operate by a centrally located power button below the viewfinder. The dynamic range of the TIC is Zero degrees to 1200 Fahrenheit which is shown by a RHI or Relative Heat Indicator Bar, that goes up and down based on the overall temperature within the TIC’s Field of View. The Bullard T4 Series has a very narrow vertical Field of View (F.O.V.) which is only 32 degrees vertically. Once the overall temperature within the TIC’s F.O.V. is over 300 degrees the TIC will switch to Low Sense Mode which will be indicated by a green triangle in the upper left-hand corner. If equipped with X-factor (Image Enhancement) the resolution of the camera is substantially greater allowing for better decision making and improved situational awareness. Insight Training LLC Project Kill The Flashover 28 The Bullard T3: The Bullard T3 is identical to the T4 & T4 Max with the following exceptions. It has a lower resolution detector (160x120) and has a 30 Hz processor. The TIC’s specifications are listed in the adjacent infographic. Eclipse LD, LDX, & LD320: (three available models in 9 different colors): The Bullard Eclipse LD is a very popular and prominent TIC due to its low cost, ease of use, and light weight almost flashlight size. This TIC is very simple to operate with the power button located in the center of the device. If equipped with the Electronic Thermal Throttle (ETT) it will be located toward the optic lens (or front) of the device. It is important to note that not all Bullard Eclipse LD are the same as this TIC is available in three different grades of resolution: 80x60, 160x120, or 320x240. In regard to fire service TIC’s the NFPA minimum resolution recommendation is 320x240 resolution. Eclipse LD-3 Models • F.O.V-31 x 42 degrees • MODES/TEMP-1 Mode/2 Temperature Modes (High/Low). • Color Palettes-1 • Resolution-One of three models: 80x60, 160x120 or 320x240 • Refresh rate- 60 Hz • DTS Ratio: 30:1 • Emissivity: .95 • Over temperature failure: 175F • NOT Intrinsically safe! • Electronic Thermal ThrottleOptional Bullard T3 Max • DYNAMIC RANGE:0-1100 DEGREES F • F.O.V: 37 X 50 • Temperature Modes: H/L • Color Palettes: (1) • Resolution: 160 x120 (20,000 Pixels) • DTS: 30 to 1 • Refresh Rate:30 Hz • Emissivity: .95 • Over Temperature Failure: 500 F • NOT INTRINSICALLY SAFE! Insight Training LLC Project Kill The Flashover 29 Electronic Thermal Throttle Feature: To activate the Thermal Throttle option, locate the two black buttons on the top of the TIC. Press the down button (the button closer to the front of the imager) to activate the Thermal Throttle. The Electronic Thermal Throttle will automatically sense the hottest area in the scene and color it blue. Continuing to press the down button (or holding it down) will further engage the Thermal Throttle and will color more of the scene blue, eventually coloring even the coolest objects blue. Each TT number has no temperature equivalent but simply increases the TIC’s sensitivity, thus this allows the end user to search for specific heat signatures. In the event, the TT is engaged during firefighting press both buttons at the same time to deactivate or reboot the TIC and it will default to standard firefighting mode. This feature is NOT to be used during firefighting as it will colorize the entire F.O.V. blue and provide no contrast for firefighters to “see.” It is recommended for use in Size-up, lost persons, overhaul, or locating overheated objects. As the above photo shows, the firefighter can clearly see areas that need to be overhauled whereas in the standard firefighting mode the temperature differences may not be significant enough to produce enough contrast to draw their attention to it. Insight Training LLC Project Kill The Flashover 30 REMEMBER! A Thermal Imaging Camera will not help a firefighter in a flashover! If used and interpreted properly it can help mitigate and prevent rapid fire progression. If firefighters ignore or fail to use it correctly they can be burned or killed. The following photo illustrates what can occur when a search crew pushes past the hose team up a thermal column (the stairs above a fire) without considering thermal severity. They were ultimately chased out of the environment and received second degree burns. The housing of this TIC would have been in excess of 1000 degrees for it to melt. Our P.P.E is not fire proof nor will it withstand superheated convective currents for long durations. Fortunately, these firefighters escaped with their lives and were able to live to learn from this incident. Insight Training LLC Project Kill The Flashover 31 The Five Key Attributes of Thermal Imaging: Field of View: (F.O.V.) The ability to see a field of view is the very windshield that the TIC views the incident through and NOT the size of the screen or viewfinder on the TIC. This windshield view is often between 37 degrees (vertically) and 50 degrees (horizontally). The human eye sees approximately 170 degrees F.O.V. which means we are missing a large part of the incident scene if we do not scan the area accordingly. In the following image, notice the difference between the F.O.V. between the TIC’s view and the helmet cam’s view. This emphasizes the importance of understanding the F.O.V of your TIC. Notice the diminished F.O.V of the TIC versus the helmet cam. Insight Training LLC Project Kill The Flashover 32 Modes and Color Palettes: The Temperature Modes and Functional (or Application) modes of the TIC determine the range of the color palette and its specific usage. For example, there are many TICS’ currently available with up to eight functional modes (user specific) and up to three temperature modes (Most TIC’s fall into the two categories: High & Low Sensitivity –or- High, Medium, & Low Sensitivity). This can become confusing and detrimental if the organization doesn’t have a standard operating guideline on which function mode to use in specific situations and if firefighters aren’t well trained to the color palette and associated temperatures. A fire department that trains its firefighters on the same functional mode, to understand the associated color palettes, and understand the varying temperatures in each mode will be successful in implementing Tactical TIC usage. Key Point: “It is critically important that a firefighter be trained to interpret the image based on the functional mode of the TIC and the associated color palette dependent upon the temperature mode that it is in.” (photo courtesy of Bullard). Insight Training LLC Project Kill The Flashover 33 The previous image displayed is a Bullard Eclipse LDX (with X Factor Scene Enhancement) in the Low Sense mode with arrows superimposed to assist the firefighter in better understanding the overall image. The RHI-Relative Heat Indicator is on the Right-Hand Side and ranges from zero to 1200 degrees. To make rapid strategic decision making easier the temperatures are associated with specific colors that are easy for the firefighter to remember. Firefighters who learn the specific color palette of their TIC in the low sensitivity (indicated by an EI or L symbol in some older models) mode would benefit from memorizing the temperature and associated color range to better diagnose the thermal severity of the environment. It is of utmost importance for firefighters to see the difference and loss of detail in the image as TIC switches to Low Sense Mode. The TIC will adjust to see the heat source better but typically there will be “noise” on the surrounding edges which obscure any finite details such as doors, windows, and potential victims. Insight Training LLC Project Kill The Flashover 34 In most thermal imagers, the Low Sense Mode will be indicated by any of the following: EI Mode: stands for electronic integration and in this case, it tells the end user that the overall F.O.V. is over 300 degrees Fahrenheit. This mode is generally indicated by noting a green triangle that appears in the upper left-hand corner of the display. This is found in older thermal imaging camera models such as the Bullard T3. L Mode: Low Sense Mode in older models the user may see an L in the lower lefthand corner (for example the older MSA series TIC’s) indicative of overall F.O.V being over 300 degrees Fahrenheit. Low Sensitivity Mode in newer model TIC’s, especially NFPA 1801 Certified TIC’s will have a green triangle in the upper left-hand corner indicative of overall F.O.V. being over 300 degrees Fahrenheit. Insight Training LLC Project Kill The Flashover 35 Certain temperature ranges are color associated so that firefighters can make quick decisions about the environment they are approaching. • Yellow: 500-799 F • Orange: 800-999 F • Red: 1000-1200 F Understanding the Language of the TIC: For this example, a Bullard thermogram, or thermal picture, of a fire room will be used. Each TIC has a specific “language” Insight Training LLC Project Kill The Flashover 36 of its own. It is critically important that a firefighter understand the screen symbols and the associated temperatures with each temperature mode of the thermal imaging camera. As seen in the photo below, firefighters can gain valuable information from proper interpretation of the image displayed on this Bullard TIC screen. One can see that the TIC is in Low sense mode due to the Triangle symbol in the upper lefthand corner which equates to the majority of the Field of View being over 300 degrees Fahrenheit. Firefighters can see the fires severity as the thermal convective heat currents are moving from left to right with the fire’s location being to the left. The image also shows that there is significant radiative feedback that is causing the neutral plane or thermal gradient to descend downwards heating up the contents of the room. The thermal gradient or neutral plane is at 75% of the room height indicating the fire is growing and spreading laterally across the ceiling towards the air and cooler spaces as fire travels from hot to cold. Core Over Temperature Indicator: A red triangle in the top center of the image display will appear and flash when the internal core temperature of the TIC is approaching a level that will damage its components. The TIC will shut down automatically to protect itself typically within 30-60 seconds of the indicator appearing. If a firefighter is not oriented and this occurs there are two concerns Insight Training LLC Project Kill The Flashover 37 they need to address. First, if the internal core temperature of a well-insulated, vacuum sealed, thermal imaging camera is reaching close to 500 degrees the environment the firefighter will lead to their injury or death if not dealt with or retreated from. Secondly, the if the firefighter has failed to stay oriented and the TIC shuts down they are now in a MAY-DAY Situation. Temperature Target Area (DTM or Spot Temperature): This is the focal point of the TIC which displays the Temperature Target Area located in the lower right corner. Warning! This is a small area of measurement and should not be used to make decisions about the overall environment. TRAINING IS REQUIRED BEFORE USE. DO NOT use the TEMPERATURE INDICATOR readings as exact measurements. DO NOT make a critical decision based solely on a temperature reading. However, it can be used for overhaul and checking the temperatures of overheated equipment. Spot Temperature • Spot Size Ratio or Distance to Spot Ratio is the distance from the TIC to the target, COMPARED to the size of the spot being measured. • We have to remember the measurement result is an average of the whole spot. (usually 3-5 pixels) • Overheated equipment, light ballasts, etc. ? Insight Training LLC Project Kill The Flashover 38 Resolution: If a firefighter doesn’t know the resolution of their TIC it can mean the difference between making a save and missing one. For example, a crew searching a 12x12 bedroom using the directed search method could possibly miss a small child’s hand if it were more than 7 feet away. The image would present itself as blurry and may be difficult to discern in the environment firefighters regularly face. What other reasons should resolution matter to us as firefighters? What if we miss a small hand of a child? Notice the differences in how my daughters hand is visible at varying distances in the image to the left. Or a small ember burning in the wall or attic in overhaul? Remember! The higher the resolution the better our chances will be to see the finite details of an environment where missing one small cue may be the difference between life and death and extinguishment or rekindle. Insight Training LLC Project Kill The Flashover 39 Distance to Spot Ratio: is the TIC's ability to successfully measure a spot temperature (the cross hairs or focal point) from a specific distance. The effective range that the majority of TIC’s measure accurately is at the focal point; which is typically a 12-inch circle. This can be compared to a flash light beam. As one stands closer to the wall with the flashlight the beam is more focused and intense (more accurate). And as one walks further away the spot becomes larger and less intense (less accurate). An individual holding a TIC should be aware of the TIC’s distance to spot ratio to accurately diagnose the thermal environment and read the entire image not merely the spot temperature. For example, a firefighter viewing a structure 30 feet way may see temperatures at 71 degrees but when within 10 feet the temperatures are 300 degrees! This is due to IR energy dissipates due to distance and other factors along with the TIC’s ability only to “see” effectively within a certain distance. Key Point: Isn’t Thermal Imaging just point and shoot? What’s wrong with reading the spot temperature or Direct Temperature Measurement?) Because it’s a spot temperature measurement not the overall thermal environment and many firefighters have suffered for failing to recognize this! (Photo credit Project Kill the Flashover). This photo shows a spot temperature of 87 degrees Fahrenheit and it is quite obvious the environment within the Field of View of the TIC is approximately 500 degrees Fahrenheit or more! Insight Training LLC Project Kill The Flashover 40 The Importance of Emissivity: Merriam Webster defines Emissivity as “the relative power of a surface to emit heat by radiation.” But as firefighters, have we considered that the materials we are viewing emit heat at differing rates? Do they all “look” the same to the thermal imaging camera? Firefighters need to understand that fire service thermal imaging cameras are set at .95 emissivity rating which is the common number for most construction materials, human skin, soot, and most objects that are made of carbon. All materials are between an emissivity between zero and one. Objects that have an emissivity closer to zero are considered a “perfect mirror” that reflect infrared energy whereas objects that are closer to one are considered a “perfect emitter.” But there are numerous materials in our homes with varying emissivity values that will cause the TIC to show a temperature that isn’t accurate. For example, a polished aluminum pot that is boiling water on a stove could show up at near room temperature because its emissivity value is 0.05 which makes it almost a perfect mirror. The “shiny” aluminum pot reflects IR energy even though it is quite hot. The TIC will display that the “shiny” object is closer to the relative temperature of the environment around it. What objects are in household’s today that would lead a firefighter to view the temperature incorrectly or be unable to accurately identify the environment? Consider the increase use of stainless steel in appliances, glass, shiny floors, etc. all would prevent a firefighter from interpreting the image correctly. As a general rule, if it reflects or it is shiny, it needs to be checked as the TIC will NOT read the temperature correctly. Insight Training LLC Project Kill The Flashover 41 IV. Application: Tactical 360 In the realm of firefighting, if we don’t offer an experientially relevant example to our firefighters the subject matter will ultimately lose all of its relevance. In other words, if they don’t have a way that they can apply this information then it will fail to be applied. Before we can address the issue of fire ground application we have to overcome another barrier: the failure to carry the TIC. In teaching this course internationally, a common thread emerges: the TIC stays on the fire apparatus more than it is actually used. If we are going to apply the TIC to maximize and enhance our strategies and tactics we must incorporate it as a part of our PPE. In other words, a firefighter would not wear an SCBA without a PASS device; neither should a firefighter whose department has purchased and trained them on Tactical TIC use would leave their tool sitting in the charger. Sadly, in the majority of the LODD’s that have been researched show that out of 38% of those incidents the TIC stayed on the charger on the fire apparatus. Once we understand its importance and understand how to interpret it now it’s time to use it! Let’s start with where we start on the fire ground: Our Size-Up. A tactical 360 is a 360-degree survey of a structure on fire from three perspectives: Tactically, Thermally, and Three dimensionally. Whereas a traditional 360 is walkaround survey of the incident scene that allows the Incident Commander to better formulate their Incident Action Plan based on the “big picture” and all of the critical fire ground factors that are specific to that incident. The Tactical 360 is an enhanced version of the standard 360-degree survey. Insight Training LLC Project Kill The Flashover 42 Tragically we already know that many firefighters have died because of hidden or unseen dangers. Therefore, incidents can often be deceptive from a onesided view and hide critical factors that can and will kill firefighters. Also, the Tactical 360 allows the Incident Commander to see a side of the fire previously unseen: the thermal severity, thermal cues, and thermal progression of the fire. The Tactical 360 can aid in possibly locating victims, the location & severity of the fire, identify the flow path, and the opportunity to control any critical fire ground factors that may go unnoticed such as closing open doors to prevent fire growth, controlling utilities as they walk around, and possibly removing an occupant that may be just inside a door or hanging out a window. The Tactical 360 doesn’t discard nor discount this information, but enhances what we know thereby building upon it. As a firefighter, we already have a foundation and understanding of the concept now we will build upon this skill by viewing the 360 from three perspectives. Our first perspective is to view the incident tactically. The infographic below displays a common acronym taught to us by John Norman using the COAL WAS WEALTH mnemonic. The letters that are highlighted in red are areas that can be enhanced by using the TIC. The fire service currently does a great job performing the necessary tasks based upon the conditions presented to them. Insight Training LLC Project Kill The Flashover 43 An Incident Commander can quickly identify the type of construction which in can range from colonial, rambler or ranch, Cape Cod, split foyer, split level, balloon frame, hybrid, McMansion/estate homes, and cluster homes. In the colonial example “typically has two stories above ground with a front door leads into the main entry & stairwell for the structure” (Single-Family Dwelling Manual, 3rd Edition p.2). This type of construction is common across the United States as “new construction” which is typically light weight wood frame construction. This type of construction will be well insulated and are required to be pressure tested to receive their energy efficiency rating. Firefighters who carry their TIC can quickly identify thermal bridges (areas where energy is being transferred via conduction) and areas where doors, windows, or pipe chases are sealed with very flammable insulation. This insulation fails under fire conditions and provides an easy to identify thermal cue of the location of the fire such as the photo below. In this photo, there is 1000-degree Fahrenheit fire behind this window with only this small thermal signature on the top of the window. (photo courtesy of Project Kill the Flashover) Insight Training LLC Project Kill The Flashover 44 In the case of a Ranch or a Rambler home is “typically one and half stories above ground” (Single-Family Dwelling Manual, 3rd Edition p.3) and are typically brick construction with dimensional lumber. In regard to noting thermal signatures, the Incident commander would be wise to look at the roof line, gable vents, dryer vents, doors and windows, and look for crawl space vents as shown in the photo below. (Photo Courtesy of Max Fire Training) We can clearly see high heat signatures in the majority of this photo but the key thermal cues to note are the ones that are underneath the structure. Numerous LODD reports state the recommendation that a 360 should be completed and a TIC should be used to locate & identify the severity of the fire. This is value of the thermal perspective that is often overlooked because of our failure to carry the TIC or interpret the data correctly. Notice the Crawl Space Vents! Insight Training LLC Project Kill The Flashover 45 Learning to Predict the Fire’s Progression: We will now improve the incident action planning by also viewing the incident from a tactical perspective instead of merely an extinguishment perspective. In a matter of seconds, an Incident Commander must consider a myriad of possibilities. By dividing this planning into four areas of time it helps to prioritize the critical fire ground factors. These four areas are the NOW, NEXT, FUTURE, PAST Decision Model which are similar to many RPDM (Recognition Prime Decision Making) models that are taught today that quickly determine the problem, find a solution and implement that solution based on prior experiences. This four-quadrant model consists of: Right NOW, then what is NEXT with a prediction of the Future while considering the Past experiences and the speed of the fire growth in front of the Incident Commander. What do we have? As we arrive we are viewing the current position of the incidents progression. Next, a proactive Incident Commander is always thinking two steps ahead of the incident. Therefore, we are attempting to forecast where a fire is progressing towards either in a positive or negative way and planning accordingly. Then we Insight Training LLC Project Kill The Flashover 46 are attempting to view a glimpse into the Future. For example, after arriving on the scene of a one story 1200 square foot single family dwelling, consisting of light weight construction, with fire visible from the A-side windows we can predict that we have roughly a few minutes or less to identify, defend, or kill the extreme fire behavior based on our knowledge of light weight construction and fire dynamics. Our past learnings tell us that buildings of this type fail or collapse quickly under heavy fire conditions so our Incident Action Plan will address the conditions accordingly. As the Incident Commander completes their Tactical 360, they can compare the initial view of the incident to the current view and predict fire growth, severity, and direction of travel. This information should be communicated to the crews on the fireground in order to aid in their strategies and tactics. Insight Training LLC Project Kill The Flashover 47 Implementing the Tactical 360: A properly trained Incident Commander who conducts a Tactical 360 will view the incident tactically looking for standard tactical considerations: life hazards, construction, location of fire, basements, etc. As they view each division they will then pause and view it through the eyes of the Thermal Imaging Camera. As the Incident Commander begins their Tactical 360 it is important to note the areas of where the occupant may normally use for entrance/egress. We must remember the resident will be trying to escape from the fire and the initial attack teams typically find the victim as they are going towards the fire. Therefore, the initial size-up and 360 should begin by checking the entrance/egress point for victims as they are typically found within 5-7’ from the door. In addition to checking the entrance/egress point the officer needs to check the door for heat prior to opening it, once the door is open they would look for the location of the fire, the configuration or lay-out of the structure, and then close the door while the initial attack crew is getting their line deployed. This initial information is critical as the Incident Commander now has an idea of the interior lay-out of the structure. As the officer completes their 360 they are looking for the thermal cues or thermal bridges where heat energy is being transferred from the interior which provides an indicator of the fire’s location. As we can see in the photo above (courtesy of Insight Training LLC) the crew leader is checking for victims, confirming the fire’s location/severity, and determining the lay-out of the structure with the TIC. Insight Training LLC Project Kill The Flashover 48 Thermal bridges are a concept that building engineers try to eliminate as they allow energy to leak out of a building. Therefore, from a strategy & tactics perspective, many times firefighters have smoke visible from numerous parts of a structure but when viewed thought the TIC they can see the areas that have high surface temperatures as TIC’s do not read gas or smoke temperatures. One can then deduct that if the surfaces are superheated enough to transmit heat through the structure that there is significant fire/heat behind it. This can enhance the strategic decision making of the incident commander in regard to: • Initial attack line placement • Search & Rescue Efforts • Ventilation Efforts • Location & Severity of the fire • Exposure Fire Concerns • Fire Below Grade (basements, crawl space, etc.) Insight Training LLC Project Kill The Flashover 49 In the diagram above, we can see many examples of thermal bridges that may show indications of fire location such as bath fan vents, fireplace vents, dryer vents, range hood vents, pipe chases, drain lines for HVAC, gas lines, crawl space vents, gable vents, etc. Notice, in the photo below the metal door knob is over 300 degrees Fahrenheit but there are no other thermal indicators through the insulated steel door. This is a good example of a thermal bridge from a sizeup perspective. If a metal has a shiny surface, a fire service TIC will not read the surface temperature accurately unless the metal is nearing its melting point! Insight Training LLC Project Kill The Flashover 50 V. Go/No-Go Decision Making: This is one of the most misunderstood concepts that is being shared by many fire service instructors today. Project Kill the Flashover first introduced this concept with not just a phrase but with a four-part decision model based on data & not opinion. This model was conceived in order to help firefighters make more informed decisions prior to moving forward. However, we must emphasize that the Go/No-Go decision model doesn’t mean Never Go; it simply means we must mitigate the factors or variables that will cause us thermal insult or lead to rapid fire growth prior to moving forward. There are too many variables to have one absolute model that guarantees success on an ever-changing fire ground. The Go, No/Go Decision Model consists of four components but can be applied in the following manner: 1) The Tactical 360:(We first begin by looking for Thermal Cues)-First Identify the flow path (Ventilation Profile), location & severity of the fire, look for cold spots (and areas of low pressure) as this is where the fire may travel next, and any signs of a victim. Firefighters need to be constantly aware of the dangers of entering into an uncontrolled air track (flow path) as many LODD’s and injuries have occurred from not being aware of the flow path and its progression/direction. Next, we should look for heat signatures on the top of window frames and doors as the frames will indicate thermal cues. Also note the temps of Side A and compare it again when the firefighter completes their 360. Also, one should check to ensure that their distance is the same so that the Insight Training LLC Project Kill The Flashover 51 temperatures will be consistent and that we are within the optimal distance of the TIC's range. As the first due officer, one may choose to open the front door and make a quick check for victims, confirm the layout of the home, and the location of the fire. Is so, use an extinguisher to 3-D the door which is to place moisture where the heated gases will spill out upon entry thereby cooling them and preventing/slowing vent point ignition upon opening the door. Firefighters are trained to bleed the air from their attack line and check their nozzle pattern prior to making entry but in many cases the water is wasted by discharging it upon the ground. By applying it copiously to the door frame it accomplishes the task of bleeding the line, checking the pattern, and once the door is opened it slows the fire growth by cooling any superheated gases that exit the opening. A well-trained crew leader will be aware of the fire’s location, and its severity by the completion of their Tactical 360. They would take into account that if the fire is three rooms away from their entry point and they are entering on a cooler area that the fire will move from Hot to Cold and if the door remains open the fire will move towards the air. Therefore, the access point is cooled prior to opening to slow the fires progression and to allow time to assess the environment before directing their crews. As the above photo illustrates, the attack crew is well aware that there is significant heat behind this door. They do NOT open the door until their PPE is fully donned and their attack line is charged. Insight Training LLC Project Kill The Flashover 52 Otherwise they will allow the fire to grow and intensify. (photo courtesy of KTF Burns). 2) Access or Making Entry: If prior to entry the following variables are noted: Turbulent and High Velocity Smoke, a rapidly descending neutral plane that is occupying more than 50% of the access opening, temperatures at or above 500 degrees (or of the overall space in front of the firefighter), and if they are not able to observe any data through the Thermal Imaging Camera due to saturation or overtemperature which means the temperatures of the environment are beyond the capabilities of the TIC and also our PPE; then all of these are indicators of a No-Go scenario. The crew leader would have the nozzle man positioned away from the opening so they are not in the exhaust. And direct the stream to properly cool the environment down within the acceptable working range of our PPE. The key in directing the nozzle man’s efforts is to effectively use the reach of the stream prior to reaching the superheated areas. By Insight Training LLC Project Kill The Flashover 53 cooling where they are and where they are going they are maintaining a ‘survivable space.’ Other examples of mitigation efforts could include cooling the environment below 500 degrees, controlling the air (by use of door control, hanging a curtain or smoke blocker), and/or changing the focal point of the TIC to a lower height to observe the thermal severity of the environment to more accurately determine the conditions they are facing. As we can see in the adjacent photos, these are two examples of NoGo scenario’s initially. The overall temperatures in the first photo are over 1000 degrees Fahrenheit which need to be cooled prior to making entry and this photo reinforces why we scan a room prior to sending our firefighters into it. This photo was taken 1 minute prior to flashover or rapid-fire progression. (photos courtesy of Bullard). In the second photo, we see turbulent smoke with a neutral plane lower than 50% of the opening. Both are indicators of rapid fire growth that need to be mitigated prior to making entry. Insight Training LLC Project Kill The Flashover 54 Why 500 degrees Fahrenheit? (260 Degrees Celsius) In the beginning of the text, we discussed the importance of understanding heat and temperature. Firefighters need to understand how their PPE works, what its limitations are, and how temperature & duration of exposure affects their protective ensembles ability to protect them. A quick study of our PPE & fire behavior phenomenon reveals a common number at which changes/failures occur and that is 500 degrees Fahrenheit. Our PPE begins to char at 572 degrees Fahrenheit (Nomex material) and PBI begins to char at 1000 degrees Fahrenheit, our SCBA face piece lens (made of 2-3 mm of polycarbonate) begins to melt at 447 degrees Fahrenheit, and the fires growth increases exponentially after 500 degrees Fahrenheit. Insight Training LLC Project Kill The Flashover 55 Why control the air to the fire? In the U.S. fire service, we have operated under a ventilation paradigm for many years. Unfortunately, with the introduction of high heat release rate fuels (which are synthetics derived from gasoline or petroleum derivatives) the fire’s growth is now exponentially faster than in the past. By controlling the air, we thereby control the fire. Many ventilation-induced flashovers are actually caused by the fire department after their arrival by “opening up” without controlling the environment (e.g. doors being opened, windows failing or being broken out). Thus, preventing air to the fire decays the fire and slows the turbulence/air entrainment to the fire. In many cases, the firefighters fail to read the building, identify the flow path, and how their efforts can negatively affect their suppression efforts or fail to use a model such as the VP: BE-SAHF model. In many cases the neutral plane (or interface layer) is only identifiable at an opening from the exterior. But what happens when firefighters are in zero visibility? How can they identify when this interface layer is beginning to descend? In thermography, overall radiant heat layer forms a thermal layer which is easily identified through a TIC. This is known as a thermal gradient. This image or thermal gradient varies dependent upon the TIC, its resolution, and the associated color palettes. In general, a firefighter will be able to notice the heat beginning to descend by this thermal gradient which is an indication of rapid fire progression as the overall heat becomes closer to the fuel load in the room the chances of ignition increase exponentially. Insight Training LLC Project Kill The Flashover 56 Why is the Neutral Plane important? The neutral plane is a valuable indicator of the fire’s growth, location, and the area where the fire’s intake and exhaust is separated. In many cases it isn’t easily visible with the naked eye thus the TIC makes it easier to identify. A neutral plane that is rapidly collapsing/descending is indicative of fire growth, is often accompanied by turbulent (fast moving) smoke and is also an indicator that the fire is attempting to convert that opening into an exhaust. Many firefighters have perished in unidirectional flow-paths (exhausts) and our PPE will not withstand moving convective heat currents for very long without thermal insult. The infographic to the right illustrates a bidirectional flow with the neutral plane (zone). The firefighters in this image are advancing into a bi-directional flow which is exhausting superheated gases into their PPE. This would have been prevented/mitigated through the Tactical Use of a TIC as part of the Go/No Decision-Making Model. Insight Training LLC Project Kill The Flashover 57 Go/No Go decision making isn’t merely for when firefighters are making entry into the structure. When used properly, it should serve as a guide prior to advancing forward. A trained crew leader should scan the environment they are about to enter, mitigate those four variables, and then move to their next designated point within that area they just cooled. And then the process should be repeated. For example, a crew could move from one threshold to another threshold of a room, mitigate the environment in front of them, and then move forward. This isn’t a guarantee that conditions will worsen but with the use of technology and our training it creates a more stable environment (Thermal Class II) in which our PPE is meant to function for longer durations without thermal insult. Once these variables have been addressed the firefighters should see: A) Slow moving smoke. B) Neutral plane rising C) Temperatures below 500 degrees. E) Observable data on the TIC. By practicing this model not merely at the access point but as firefighter’s transition through the structure they can maintain a thermally survivable space. This process must be continually repeated to confirm that their suppression efforts are working and the conditions are not worsening. Insight Training LLC Project Kill The Flashover 58 Key Points in understanding the Go/No Decision-Making Model: A common misconception of firefighters is that Thermal Imaging Cameras read air/gas temperatures. However, Fire Service TIC’s do not read air temperatures; they read infrared radiation or surface temperatures. Technically, Fire Service TIC’s see IR energy within a specific wavelength of light at a preset emissivity and only three gases fall into that range: Hydrogen Cyanide, Ethane, & Ethylene. As the adjacent photo illustrates, we can see convective heat currents such as these radiating from the Max Fire Box. This allows firefighters to see these fire behaviors in a safe environment and trains them to recognize them when they see them in an actual fire ground incident. One should be aware that even with a TIC we are not seeing everything: “Note that even though CO, CO2, and water vapor are not visible to us in the visible spectrum, and in parts of the infrared spectrum they block out significant quantities of the infrared radiation” (NIST Technical Note 1499, p.13). Notice the smoke and gases are not easily visible through the eyes of the TIC once the door is controlled in the Max Fire Box Photo. Insight Training LLC Project Kill The Flashover 59 Thermal Imaging Camera’s work based on contrast or reading temperature differences (which is one of the performance metrics in determining resolution we will learn about later regarding NFPA 1801). If there is no temperature difference in the environment in front of the firefighter, for example, an environment that is uniformly heated, there will be no contrast or visibility. Firefighters can “create” contrast or temperature differences by cooling the environment, and by pointing the TIC at an object of a different temperature. It’s important to note that as firefighters operate in a fire environment that the temperatures around them may be much hotter due to the gas temperatures. This is why we advocate controlling the air and not allowing smoke or convective heat currents to be moving around firefighters. Firefighters need to also be aware that color isn’t always indicative of thermal severity with a TIC. As in the photo below, there is turbulent gray heat currents above the firefighter’s head which are an indication of fire growth. (photo courtesy KTF Burns). Insight Training LLC Project Kill The Flashover 60 In the next photo, we see turbulent gray scale heat currents above the firefighter’s head. In many cases there are convective heat currents visible in the view of the TIC that are in ‘gray scale’ which are indicative of rapid fire growth. Many firefighters have failed to identify these and suffered the results of rapid fire growth in the result of critical burns or line of duty deaths. A crew leader should be constantly reassessing the environment in front of them, where they are, and behind them to ensure thermal stability. And if they feel that something isn’t right(conditions rapidly changing), or they feel heat, and the TIC is registering the environment as cool; trust your training and respond accordingly. The changes in the modern fire environment happen in seconds, and this requires a diligent, disciplined, and situationally aware crew leader who is monitoring conditions in order to prevent them from overwhelming Insight Training LLC Project Kill The Flashover 61 their firefighters. We recommend live fire training, training evolutions such as with the Max Fire Box, and viewing thermal imaging videos in order to be better prepared for the challenges of today’s fire ground. Experiencing fire behavior phenomena should occur under the instruction of a senior instructor before a firefighter witnesses these events on the fire ground. Without this training, firefighters may fail to respond until it’s too late. In summary, we offer three modern principles while assessing each compartment during firefighting efforts: 1)Know the temperature! 2) Stop the Air! 3)Send Water Ahead! (photo courtesy KTF Burns & Chief Joe Starnes) Insight Training LLC Project Kill The Flashover 62 VI. Enhanced Stream Placement: Tactical Thermal Imaging allows firefighters to direct their streams more efficiently toward where the water is needed most rather than all over or missing superheated areas. In many cases, of watching firefighters on standard training fires I have noted that firefighters only briefly open the nozzle before advancing and there are often temperatures of 800-1000 degrees still behind them. A trained crew leader can guide the efforts of the stream and ensure that superheated areas are “erased” and not merely penciled. In the above photo, the entry team moves in and briefly flows water with a straight stream to the ceiling before moving forward. The superheated ceiling temperatures that are left behind were in excess of 900 degrees Fahrenheit. If the air isn’t controlled and the fire reignites, it will rapidly progress to flashover conditions and could trap, injure, or kill firefighters or victim’s due to the failure of truly extinguishing not just the fire but the heat. In enhanced stream placement, it takes coordination and communication between the crew leader and the nozzle person to ensure its overall effectiveness. Insight Training LLC Project Kill The Flashover 63 Why Most Fire Streams are Ineffective: In our training as firefighters, we are taught fire stream application based on a methodology or a pattern (such as a T, Z, or an O). In most cases, the emphasis is not placed on cooling the environment where they are and where they are going efficiently. In the he majority of training fires, the firefighters are taught to briefly ‘pencil’ the ceiling prior to moving towards the target area. Unfortunately, this method fails to adequately reduce the temperatures around them and prevent any rapid-fire progression from occurring. By implementing tactical thermal imaging, a crew leader can guide the nozzle man’s efforts and effectively ‘erase’ the superheated areas around them thereby preventing rapid fire progression. As seen in the photo below, this stream is being used to “erase” the heat rather than pencil the ceiling. Insight Training LLC Project Kill The Flashover 64 Crew leaders can confirm that their efforts are working through enhanced stream placement. By guiding the nozzle man prior to moving forward, the water is placed where it is needed and the temperatures are reduced & confirmed prior to moving forward. This accomplishes many powerful and impactful objectives: • The environment is cooled producing more survivable temperatures for victims and firefighters. • After a few moments of proper water application visibility will increase which can allow firefighters to locate victims more efficiently. • A crew leader can locate the fire and after applying water they can tell if they are reaching the target room (the seat of the fire) of if they are cooling the access path. • In many NIOSH LODD reports, they indicate the prior to the loss of a firefighter the report states that they were having difficulty locating & extinguishing the fire. When properly applied, this tactic eliminates this concern. Insight Training LLC Project Kill The Flashover 65 As a trained crew leader, there are several points to mention in Enhanced Stream Placement: • Always communicate in terms that can be understood in zero visibility such as telling the nozzle man to direct their stream from their 10 o’clock to their 2 o’clock position. We don’t recommend saying “to your left or right” because they may be turned differently and the nozzle man doesn’t have a TIC to see what you’re seeing unless you take the time to show them. • When directing the stream, we advocate beginning with a sweep of the floor. First, TIC’s have difficulty in discerning holes in floors due to uniform temperatures or lack of contrast. As water enters the fire environment, it cools this area creating contrast which shows several points to consider that otherwise may go unnoticed: holes in the floor, potential victims, and it cools the surfaces that firefighters are about to crawl onto. Lloyd Layman’s work proved that if water is directed into where the air is entrained it will reach areas that a fire stream will not be able to reach. Therefore, when a crew leader directs the nozzle man to flow water across the floor, this is also considered an under-pressure attack which directs moisture into the fires intake. Project Kill the Flashover’s research has shown that this technique decays the fire, cools the temperatures, and provides less thermal upset by beginning low then directing the stream to the superheated upper layers. • Never allow the crew to go anywhere that water doesn’t go first: A crew leader will direct the stream with the TIC and then direct the crew to move to a designated position within the area that was just cooled & confirmed the temperatures have been reduced. Each compartment is cooled, checked, confirmed and the process is repeated. Insight Training LLC Project Kill The Flashover 66 • Use the reach of the stream: A typical nozzle can extend water 30-60 feet. Enhanced stream placement takes advantage of the fact that the heat is erased prior to firefighters being underneath of it. By cooling the areas before they get there it reduces the thermal insult and cumulative heat exposure to their PPE. VII. Enhanced Search Methodology & RIC The use of thermal imaging cameras has enhanced the firefighter’s overall effectiveness particularly in the area of searching for victims or downed firefighters. In the late 90’s several large and well-known fire departments were invited to participate in a study. They were given two identical search scenarios: one search evolution was conducted without a TIC and the other search evolution was conducted with a TIC. The results were staggering. Without the use of a TIC the search crews missed the victims 60% of the time whereas they found the victim with the TIC while searching 99% of the time. In addition to this the total search time was greatly reduced. A staggering fact that came out of this study is this: Every firefighter trained and equipped with a Thermal Imaging Camera made it out of the structure 100% of the time! This fact alone should cause firefighters to carry our TIC. Therefore, our enhanced ability to conduct a search through the use of a TIC is an overall improvement but before we move forward into that we must discuss the dangers of over reliance on the use of a TIC while conducting a search. In addition to this, many firefighters are trained incorrectly when searching for a victim or downed firefighter they are often looking for a white hot victim. When in fact, the victim or downed firefighter will Insight Training LLC Project Kill The Flashover 67 present on the TIC display based on the overall temperature of the environment within the Field of View. Firefighters should be training on the following method: • Simultaneous Fire Attack & Search: Statistically, the initial attack team will have the best opportunity to make a rescue. Prior to starting their Tactical 360, the attack crew should take a quick look at the primary acces point. This quick look provides valuable information such as fire location, building lay-out, and the possiblity of locating a victim as many our found within 5- 7 feet from a doorway. Remember, they are running away from the fire and we are moving toward it. Our paths may intersect so be ready and be watchful! A victim can be hard to spot based on the focus and temperature mode of the TIC. The Crew leader should consider scanning high, medium, and low heights and letting the TIC adjust. Firefighters can be directed to check areas between where the hose has been advanced, the adjacent wall, or within the space that has been cooled by their enhanced stream placement. This enhances their efforts as they are moving hose and searching the area that they are moving through. Insight Training LLC Project Kill The Flashover 68 For example, if a crew is searching a 12x12 bedroom and the crew leader is directing their search with a TIC from the door way while staying oriented; the crew leader should scan the room high prior to their entry to check for thermal threat. The crew leader checks for superheated temperatures, signs of structural failure (such as exposed & deformed trusses). (photo courtesy of Scott Safety). The crew leader then scans again at medium height gaining valuable Insight Training LLC Project Kill The Flashover 69 information such as egress points, room & furniture layout, and possible victim locations. The crew leader can then give the go signal for the search to begin. By using gas cooling techniques, or short bursts of water into the upper environment, this creates two benefits during the search. First, it creates visibility for firefighters by contracting the gases and second it creates contrast or a temperature difference which may be the difference between firefighters finding the victim or missing them. The crew leader then scans at low heights taking time to allow the TIC to adjust to the lower temperatures at the floor. This allows the camera to switch to a higher sense mode (a lower temperature range) which will show more details. Many older Thermal Imagers can take up to two seconds to adjust thus our scans should be slower while our searching efforts should be quick. The Crew Leader will also be looking for thermal cues on the floor such as signs of fire beneath their crew, radiative feedback on the flooring that may cause thermal insult to the crew. Notice the superheated floor temperatures and the indicators of pyrolysis on the furniture in the next photo that is courtesy of Kill the Flashover. Insight Training LLC Project Kill The Flashover 70 A well-trained crew leader will know the resolution of the TIC which also dictates the effective range of the TIC. This will cause a crew leader to stay within the optimal range to be truly effective (most often is between 7-20'). For example, if the area that is to be searched is outside of the optimal effective range of the TIC; the crew leader directs the search within the optimal effective range, picks a new point of orientation (and also locates a secondary means of egress while searching) and then directs the search within that next effective optimal range. This may be seen as meticulous but if we are searching for a victim our efforts should be almost surgically precise. Understanding the importance of a resolution success chart could be the difference between making a save and missing one. When determining the effective resolution of a Thermal Imager it was based on the ability of the end user to identify a small child’s hand from a preset distance. This is important to note as when searching for victims we may only see one small part of their silhouette outlined in the thermal imager. This can be made more relevant by stating that if firefighters are using a T3 Bullard (160 x 120 resolution) then their effective range is 7 feet versus a T4 increases their effective range to 15 feet. Insight Training LLC Project Kill The Flashover 71 Rapid Intervention: In the event of a May-Day scenario, it is important to note that when searching for firefighters we will not typically find them in the same places as a victim nor will they present or be as easily identifiable in our thermal imaging display. (see the adjacent photo from KTF Burns & Seek Thermal) First, we must realize that any victim or firefighter will present on the thermal imaging display based on the overall temperature of the environment. For example, thermal imaging cameras display temperature differences or contrast that allows the end user to see the image. If we enter an incipient stage fire room and the room is around 100 degrees at the floor level a 98.6-degree body will not be easily identified. The crew leader could instruct the nozzle man to apply water to the ceiling or gas cool which will create a temperature difference thereby creating contrast allowing better visibility through the Thermal Imaging Camera. Insight Training LLC Project Kill The Flashover 72 Firefighters will often appear dark in superheated environments as they may be the coolest object in the room. Thus, we should not only be concerned with heat signatures but cold spots (darker areas). We should be training ourselves to investigate the dark areas on our display and look for outlines such as helmets, boots, SCBA bottles as seen in photo 8 courtesy of Scott Safety. Also, an SCBA bottle will often be the first object that is easily identified due to it will be the coldest object in the room. In the adjacent photos, note the appearance of the firefighters entering the doorway and the firefighter’s SCBA bottle hidden under the palettes. They are dark as they are the coolest object presented on the display in an area that is well over 300 degrees Fahrenheit. Insight Training LLC Project Kill The Flashover 73 Enhanced Rapid Intervention Training: Several studies have pointed out the following consistent findings in regards to firefighter MAY-DAY’s & LODD’s: • We become disoriented and lost in zero visbility environments and lose situational awareness. With Tactical TIC use, the enhanced size-up (Tactical 360) incorporates the firefighters training where they read the building (its floor-plan, fire location & severity, and locate secondary means of egress) prior to making entry. Once inside, by staying oriented (up to four ways: hose-line, search rope, a wall, or another firefighter) the TIC assists in locating secondary means of egress. In our enhanced search methodology portion, the fire attack crew is instructed to “draw” the doors and door frames with water as they move past them. When viewing the doors through the eyes of a thermal imaging camera, the crew- Insight Training LLC Project Kill The Flashover 74 leader is always aware of a secondary means or egress or area of refuge within a few feet of their crew. • Communication: In almost every LODD report, we see that failed communications or poor communication is a contrtibuting factor. In our training, we teach the crew leader to consistently communicate the following data: fire location, severity, building lay out, and secondary means of egress. • Rapid Intervention isn’t Rapid: It takes on average 12 firefighters to rescue 1 firefighter and 1 in 5 members of the rescue team will experience an emergency of their own. Studies have also shown that the majority of rescuing downed firefighters are made by the crews already inside. Our training incorporates this concept, by staying situationally aware, monitoring air (or ROAM-Rule of Air Managment), and slowing the progression of the crew so they move together as a unit. Each area is cooled, checked, communicated, and critical information is communicated to the crew before moving forward. The crew doesn’t move anywhere that the crew leader Insight Training LLC Project Kill The Flashover 75 hasn’t checked first and sent water ahead of them to ensure a thermally stable environment. In the event of a RIC scenario, it is imperattive that not only the firefighters working inside are able to not only begin rescue efforts but reenforce firefighting efforts. In many cases, fire attack efforts are abandoned thereby allowing the situation to worsen creating additional MAY-DAY situations. By equipping the nozzle man with a situational awareness TIC. They are able to staff the line, flow water where needed to protect the crew members who are effecting a rescue, and protect their movement as they extricate the downed firefighter. As seen in the adjacent photo, firefighters can stay situationally aware in zero visibility of the conditions around them. Insight Training LLC Project Kill The Flashover 76 The Danger of Uniform Temperature Environments: In many cases, firefighters may enter a room that has been heated all to one temperature such as the room adjacent to the fire room that has no ventilation. When a TIC views an area of uniform temperatures (areas that are all heated to approximately the same temperature) it sees very little discernable details. For example, a 98.6 degree victim in an incipient stage fire room that has temperatures just above 100 degrees Fahrenheit may blend in within the environment (as you can see in the photo courtesy of Insight Training LLC) due to a lack of contrast or temperature difference. Whereas, a downed firefighter trapped in a superheated room will present dark on the TIC display due to their overall temperature will most likely be the coldest object in the room. If a firefighter is lost or trapped, if they are still on air, their SCBA bottle will present dark along with their regulator lines. This is due to the compressed air Insight Training LLC Project Kill The Flashover 77 being very cold in comparison to the temperatures of the fire environment. If a Rapid Intervention Team is properly trained in Tactical Thermal Imaging they can assess a downed firefighter’s needs before they lay hands on them by noting if their regulator line is cold (the firefighter has air), if their mask is on,etc. In summary, with enhanced search methodology via Tactical Thermal Imaging, here are a few key points to remember: 1) Crew Leaders should NOT move too fast due to overconfidence with the TIC. Their crew may become lost or disoriented resulting in a May-Day. Remember, they are not seeing what you are seeing! Practice this technique: Scan, communicate to our crew, move, check crew integrity, reassess, and repeat the process. There are documented cases of MayDay’s where crew leaders went “running ahead” with a TIC thereby losing their firefighters behind them who became lost. Whether a lead search or directed search is performed, it should be done so intentionally and communication is key. 2) Pay attention to cold areas and shapes: Victims in a superheated environment will most likely be one of the coldest objects in the room. Therefore, be on the lookout for dark objects and shapes that resemble body parts, firefighter equipment or gear such as SCBA bottles which will appear dark, and thermal latency which is a thermal footprint. Notice the firefighter is hard to see in the following photos. And in the next photo we Insight Training LLC Project Kill The Flashover 78 can clearly see his SCBA bottle is the darkest or coldest object within the field of view. 3) Know the resolution of the TIC! This dictates the effective range of the TIC. This will cause a crew leader to stay within the optimal range to be truly effective (most TIC’s are between 7-15'). For example, if the area that is to be searched is outside of the optimal effective range of the TIC; the crew leader directs the search within the optimal effective range, picks a new point of orientation (and locates a secondary means of egress) and then directs the search within that next effective optimal range. Insight Training LLC Project Kill The Flashover 79 VIII. Thermal Imaging Training: After learning and comprehending the components of this program it is recommended that thermal imaging become a required component in all aspects of a fire departments firefighting training. Here are a few recommendations that will assist in the development and implementation of Tactical Thermal Imaging: • “Training should occur using the equpment specific to the department” (Whitty, p.16). Firefighters should be well versed and trained on the particular brand of thermal imaging camera they currently use. A general understanding of the five key attributes, the TIC specific application modes, Temperature Modes and associated color palettes must be understood for proper use. If the TIC has various application modes, the department should mandate a specific mode for fire ground usage in order to prevent confustion and misinterpretation as in the photos below. Insight Training LLC Project Kill The Flashover 80 This Drager TIC is set at Heat Seeking Mode, in the left photo, which shows no contrast because the max dynamic range is 300 degrees Fahrenheit whereas the photo on the right is in the standard mode which has varying thermal gradients (or shades) because it’s maximum dynamic range is 1700 degrees Fahrenheit. By standardizing the mode usage on the fireground, the fire department will eliminate any mode confustion and avoid misinterpretation of the thermal data. In many cases, if the department isn’t going to provide in-depth application based training on thermal imaging then a one button fire ground thermal imaging camera is recommended. This eliminates the possibility of improper mode usage and the chance of changing modes accidentally with a gloved hand while in a fire environment. This is shown in the adjacent photo of the Scott/ISG X380 (1 Button) model. Insight Training LLC Project Kill The Flashover 81 • Training should consist of Understanding NFPA 1801: What is NFPA 1801? NFPA 1801 is the standard on thermal Imagers for the fire service (2013 Edition) and it provides performance standards for firefighters using thermal imaging cameras in regard to: Resolution: NFPA 1801 requires that the TIC have a discernable image of such resolution that allows firefighters to interpret the data better based on: image contrast, spatial resolution, and thermal sensitivity. Image Contrast or Contrast Transfer Function (CTF) measures the difference between hot and cold objects. Spatial resolution is the number of pixels used to construct an image. Low spatial resolution TIC’s will have not be able to differentiate between two objects that are in close proximity. Thermal Sensitivity is the TIC’s ability to differentiate between objects of different temperatures. This is often defined as MRTD or minimum resolvable temperature difference. A TIC with a low MRTD (in mK or thousands of a degree measurement) will be able to differentiate or “see” the difference between items of relatively similar temperatures such as a human body and clutter. These three factors come together to produce a more defined, detailed, temperature specific image that assists firefighters in making better decisions. As a general rule, fire departments should not purchase anything lower than 320 x 240 resolution for their thermal imaging decision making cameras. This provides approximately 80,000 pixels of resolution which allows firefighters to discern a small child’s hand at approximately 15 feet away. Each individual pixel can be compared to a heat flux gauge. In short, the higher the number pixels (accompanied with a high-speed processor) will allow for more accurate diagnosis of the thermal environments that a firefighter will face. Durability: In order to meet the NFPA 1801 Certification the thermal imaging camera is put through various demanding tests to ensure it will not only survive Insight Training LLC Project Kill The Flashover 82 within the fire environment but also function at it designed parameters. The tests involve flame impingement, drop tests, and placing the TIC into a device that tumbles the TIC for a certain duration. Interoperability-This is one of the most important features of the NFPA 1801 certification. Every TIC that meets this certification will be easy to notice. It will have the following: It will have the following: (as shown in the image) •A green power button. •Universal Screen Symbols: (as shown in this adjacent photo) • Four battery bars (each indicative of 25% power), • TI Basic colorization, • Spot temperature in Celsius or Fahrenheit, Low Sensitivity Mode indicated by a green triangle in the upper left-hand corner. By purchasing NFPA 1801 approved thermal imaging camera’s a department will not have to “re-train” their members on how to operate or interpret the TIC. As the operation and color palette are all standardized. The TI Basic colorization allows firefighters to see indications of thermal severity at 300 degrees Fahrenheit whereas many TIC’s do not show any colorization until 500 degrees. Intrinsic Safety: With the many hazards that firefighters face daily, the last concern that should be on the back of their mind is the issue of intrinsic safety. Insight Training LLC Project Kill The Flashover 83 Are the tools and devices that they carry into IDLH safe or are they a potential ignition source? A TIC that meets the NFPA 1801 Certification will be intrinsically safe and meets the following criteria: ANSI/ISA 12.12.01 Class 1 Division 2 requirement: According to “the NEC and CSA define hazardous locations by three classes: Class 1: Gas or vapor hazards Class 2: Dust hazards Class 3: Fibers and flying’s Two divisions: Division 1: An environment where ignitable gases, liquids, vapors or dusts can exist Division 2: Locations where ignitable are not likely to exist” (retrieved from: https://www.blackbox.com/en-us/products/black-boxexplains/the-ansi-isa-standard-and-hazardous-locations) If the fire department plans to use the thermal imaging camera outside of the fire ground or in any other potentially hazardous environments then an NFPA 1801 certified TIC is the minimum standard that they should consider. TIC’s that are used in Hazardous Material environments that are not intrinsically safe are a potential ignition source. And in many cases, departments are not aware of this and have been deploying them into IDLH environments placing firefighters in additional harm’s way. (photo courtesy of FLIR) Insight Training LLC Project Kill The Flashover 84 . Insight Training LLC Project Kill The Flashover 85 IX. Thermal Imaging Needs Assessment/Purchasing Guidelines: I. Decide upon purchasing either a Situational Awareness TIC (mask mounted/SCBA mounted or small low cost/low resolution) or a Decision-Making TIC (High Resolution, High Dynamic Range, Fast Processor Speed, Multi-Application Use). II. Decide Upon TIC’s Primary Purpose: Firefighting only or firefighting, hazardous material response, USAR, etc. TIC’s that are designed for other uses outside of standard fire & emergency response have different criteria that need to be considered. Consider NFPA 1801 Compliance as a MUST HAVE! In the research paper “Maximizing Thermal Imaging Use in Emergency Services, author & firefighter Michael Whitty sums it up well: “Fire departments that buy NFPA 1801 approved TIC’s will not be forced to go back and use the same model as previously purchased (and be trapped by replacement pricing an outdated technology) because the standard will mean their responders will be able to use a TIC from any manufacturer that meets the standard without retraining. This is a way of future proofing your training and TIC purchase” (Whitty, p.13).Due to the constant demands upon fire department training divisions of constantly battling for enough time to maintain CEU’s, ISO hours, EMS training and more this certification allows one less training burden upon the department’s schedule. Insight Training LLC Project Kill The Flashover 86 A Decision-Making TIC that meets this certification will be easy to recognize. It will have the following: •A green power buttons. •Universal Screen Symbols: (as shown in this adjacent photo) • Four battery bars (each indicative of 25% power), • TI Basic colorization, • Spot temperature in Celsius or Fahrenheit, • Low Sensitivity Mode indicated by a green triangle in the upper lefthand corner. This standard also guarantees the following criteria are met for the department: •High resolution-320 x 240 resolution * •Intrinsically Safe •Durability: The TIC is placed through a series of demanding tests including flame contact, water immersion, and a 6’ drop onto concrete and the TIC must function properly after each test. Insight Training LLC Project Kill The Flashover 87 Resolution is one of the most important criteria for a Decision-Making TIC. There are currently many ranges of resolution available on the fire service market but the most commonly found are: • 160 x 120: 20,000 pixels • 320 x 240: 80,000 pixels • 384 x 288: 110,582 pixels Each pixel is equivalent to a temperature measurement. Therefore, a higher resolution TIC (with more pixels) will produce a more detailed image, allow for better decision making, and see temperature progressions that could be missed with a lower resolution TIC. This could be the difference between missing a victim and saving one. For example, a firefighter equipped with a 160 x 120 resolution TIC can effectively discern a small child’s hand at 7 feet away whereas a firefighter with a high-resolution TIC (384 x 288) can effectively discern a small child’s hand up to 20 feet away. Insight Training LLC Project Kill The Flashover 88 Thus far, we covered three out of the five minimum criteria for a department purchasing a Decision-Making TIC. Thermal imaging allows firefighters to make more informed decisions if they are trained properly. A Decision-Making TIC with a low MRTD (higher sensitivity) will allow the user to discern smaller details in uniform temperatures. Why is this important? Because TIC’s display images based on temperature differences. If there is a uniform temperature environment within the firefighter’s field of view the TIC is blind. Many fire service TIC’s have very low MRTD or minimum resolvable temperature difference ratings. These lower ratings allow the TIC to see fractions of a degree. In layman’s terms the lower the number, the more defined the image will be. These numbers are usually found in mK (thousandths of a degree). As the image above illustrates (courtesy of Project Kill the Flashover) a higher sensitivity (lower MRTD) allows a firefighter to be easily viewed in this image. All of these criteria for a Decision-Making TIC hinge upon the least understood which is the Frequency, commonly called Processor Speed, or Frame Update Rate. It is extremely important that any fire department purchasing a TIC understand that the minimum frequency they should purchase is 30 Hz. Why is this important? Because many thermal imaging cameras are available at 9 Hz due to an international trade law that prevents the ‘bad guys’ from buying Infrared Cameras at the sporting goods store. The human eye sees at 27 Hz and Insight Training LLC Project Kill The Flashover 89 our TV’s in our home’s display images at a minimum of 30 Hz. Why? Because 1 Hz is one cycle per second and anything less than what the human eye sees will produce a lag. This dramatically slows down the efficiency and effectiveness of the firefighter using the device. A firefighter who scans a room left to right will find that a 9 Hz TIC’s image will “freeze” for a long duration allowing the processor to catch up. In other words, it cannot process the Infrared Radiation fast enough to keep up with the demands and speed of the firefighter. In regard to Decision Making TIC’s, most of the one’s available today are 60 Hz which are very fast thereby producing an almost continuous display of information. In summary, an organization looking to purchase a thermal imaging camera must first decide on whether they are purchasing a Situational Awareness TIC or a Decision-Making TIC. Once this is completed, they must decide on its overall use. If it is for any purpose outside of firefighting, special criteria must be considered that are not mentioned in this article. For further information on this subject please check out the resources listed in the works cited section (specifically pages 12-20 in the Maximizing Thermal Imaging Use in the Emergency Services by Michael Whitty). Once the criteria for the selection is reviewed, the organization would do well to review the wealth of manufacturer literature online on the TIC’s they wish to test. Once they are well informed they can make a better decision about their purchase. They should not purchase a TIC based on its performance on the sales floor. The TIC selected should be tested in live fire evolutions and compared to the other devices. Insight Training LLC Project Kill The Flashover 90 Works Cited: Fire And Emergency Manufacturers and Services Association (20170. FEMSA User Guide. (ppP.2-4, 2-5). Fluke Thermography (2010). Thermography Terms Explained: FOV, IFOV, IFOV measurement. Thermal Imaging Blog. (p.1) Retrieved from: http://thermalimaging-blog.com/index.php/2010/03/10/thermography-terms-explained-fovifov-ifovmeasurement-on-your-infrared-camera/#.Wame4K2ZOt9 Goldfedder, Billy (2010). You & Your Bunker Gear Part 1. Firehouse Magazine. Retrieved from: http://www.firehouse.com/article/10464586/lodds-and-closecalls-near-death-on-the-fireground-fire-and-ems-emergencies-rapidintervention-teams Grimwood, Paul (2017) Euro Firefighter 2-Firefighting Tactics and Fire Engineers Handbook. D & M Heritage Press. (p.339) Kirby, Jill (2015). The Stoll Curve and PPE for an Arc Flash Rating. (p.1). Retrieved from: http://arcwear.com/blog/the-stoll-curve-and-ppe-for-an-arcflash-rating/ Mora, William R. (2003). U.S. Firefighter Disorientation Study 1979 – 2001. (p.6). Retrieved from: http://glo-jo.com/wp-content/uploads/2014/07/PDFFirefighterDisorientationStudy.pdf NIST Technical Note 1499 (2008). Performance Metrics of Firefighting Thermal Imaging Cameras – Small- and Full-Scale Experiments. NIST. (pp. 13, 18, 26-72). NIST Technical Note 1474 (2006). Thermal Environment for Electronic Equipment Used by First Responders. NIST. (p.5). Insight Training LLC Project Kill The Flashover 91 NIST Technical Note 1785 (2013). Thermal Performance of Self-Contained Breathing Apparatus Face piece Lenses Exposed to Radiant Heat Flux. NIST (p.10). Whitty, Michael (2010). Maximizing Thermal Imaging Use in Emergency Services. (p.13). retrieved from: http://fire-safety-for-all.sustainable-design.ie/wpcontent/uploads/2016/09/TIC_Maximizing-Use-in-Emergency-Services_WhittyMFB_2010.pdf Definitions were quoted from the following sources: http://v1.bullard.com/V3/resources/glossary/#Temperature Infrared Training Center. Level I Thermography Course Manual Photo Credits: Beaver Lane Fire & Rescue Volunteer Department Bullard Globe Manufacturing Project Kill The Flashover Max Fire Box & Max Fire Training Scott Safety Insight Training LLC Project Kill The Flashover 92 X. Glossary: Thermal Imaging Definitions: From A to Z Absolute temperature: Absolute zero is the lowest temperature that can be obtained in any macroscopic system. Absolute temperature means temperature measured on a scale with absolute zero as 0. This conventionally measured in units Kelvin. Absolute zero: At absolute zero, a hypothetical temperature, all molecular movement stops. All actual temperatures are above absolute zero. Absolute zero would occur at -273.16 degrees Celsius, -459.69 degrees Fahrenheit, or 0 Kelvin. Absorption: The ratio of how much infrared radiation is absorbed by a surface, and later emitted, as a percentage of the total amount of energy exposed to the surface. The percentage of absorption is basically equal to its emissivity. Accuracy: A measure of the similarity of an instrument reading to the actual value for that reading. The accuracy of temperature measurement indicators on thermal imagers is affected by emissivity, the distance from the object, the angle of the object and a number of other factors. Ambient Temperature: The temperature of the surrounding air and environment, which can impact the heat transfers around an object. Most temperature indicators on thermal imagers do not measure ambient air temperatures. Amorphous Silicon: material used to create infrared detectors. These types of detectors are used in a number of fire service thermal imagers. Angstrom: A unit of measure equal to one-thousandth of a micron. Insight Training LLC Project Kill The Flashover 93 Anomaly: The deviation of the value of a parameter, such as temperature, from its average or normal value. This is often mentioned in qualitative thermography where they are not looking for exact temperature measurements but rather temperatures outside of normal ranges. ANSI: American National Standards Institute ASNT: American Society for Non-Destructive Testing. All thermal imaging curriculum has meet the requirements of this organization. Aperture: A hole or opening that limits the amount of infrared radiation that reaches a detector. Bullard’s Thermal Throttle on the TIC and TI Commander is also called an aperture control. This is also found on manufacturer’s specification sheet as an alpha numeric designation such as f/1. When you hit the shutter release button of your camera a hole opens up that allows your cameras image sensor to catch a glimpse of the scene you’re wanting to capture. The aperture that you set impacts the size of that hole. The larger the hole the more light that gets in – the smaller the hole the less light. Aperture is measured in ‘f-stops’. The smaller the number the larger the opening. Aperture has a big impact upon depth of field. Large aperture (remember it’s a smaller number) will decrease depth of field while small aperture (larger numbers) will give you larger depth of field. Insight Training LLC Project Kill The Flashover 94 Apparent Temperature: The uncompensated reading from an IR camera where emissivity is set to 1.0 and distance is set to 0. This is the common term used when describing readings from Fire Service IR Cameras as they are generally not able to adjust their emissivity settings. Aspect Ratio: The ratio of the horizontal width to the vertical length of a display. Many video displays are 4:3, as are the infrared detectors. This is the ratio of the common television. Some newer displays have a 16:9 aspect ratio. Atmospheric Attenuation: A decrease in the intensity of Infrared Radiation due to absorption and scattering in the atmosphere. –or- The amount of signal reduction that occurs when infrared radiation travels through the atmosphere between the target and a thermal imager. Dust, humidity and precipitation can all reduce the effectiveness of the thermal imager, and the accuracy of any surface temperature measurement device. Auto Image Adjust: Automatic camera or software function that adjusts Level and Span based on image content. Background Noise: The noise naturally present in an infrared detector, independent of the signal strength or ambient temperature. This is usually masked by software, but it may occasionally appear as image graininess in very bland scenes. Blackbody: A theoretical object that radiates the maximum amount of energy at a given temperature, and absorbs the entire energy incident upon it. An ideal thermal radiator, normally used as a testing standard. The most common can be set to a specific temperature as the device emits almost 100% of the infrared radiation expected at a given temperature. Emissivity ratings are essentially a percentage value, compared to the blackbody. ( Emissivity = 1.0, Reflectance = 0.0, Transmittance = 0.0) An object that absorbs Insight Training LLC Project Kill The Flashover 95 all electromagnetic radiation that falls onto it. No radiation passes through it and none is reflected. Bland Scene: A very stable scene viewed by a thermal imager. The scene is characterized by little temperature variation and a lack of strong emitters. Bland scenes can be difficult for thermal imagers to generate quality images. Bolometer: A temperature measuring instrument using a strip thermistor to achieve higher sensitivity than a simple thermistor. Unlike thermistors which are used for contact temperature measurements, bolometers have been used to measure radiation levels. BST (Barium Strontium Titanate): A material used to create infrared detectors. These types of detectors are used in a number of fire service thermal imagers. (no longer available) BTU: British Thermal Unit-The amount of heat required to raise the temperature of 1 pound of water by 1 degree Fahrenheit. Bucket Head: A material used to create infrared detectors. These types of detectors are used in a number of fire service thermal imagers. Calibration: The process of adjusting an instrument to read accurately under specific conditions. Calorie: The standard unit of energy measurement in nutrition. Equal to one kilocalorie or 1,000 calories. Calorie: Energy unit; a single calorie is the amount of heat needed to increase the temperature of one gram of water by one degree Celsius. Insight Training LLC Project Kill The Flashover 96 Celsius (Centigrade): A scale for measuring temperature, where Absolute Zero is -273.2° C, water freezes at 0° C, and water boils at 100° C. Certification: A written testimony of qualification. Chopper Wheel: A small wheel that rotates rapidly in front of a BSTbased infrared detector. The wheel has a spiral cut out that partially blocks different portions of the detector momentarily. This process generates fluctuation in the amount of infrared energy reaching the detector, allowing it to create an accurate thermal image. Color palette: Scheme that assigns colors to various image gray levels. Condensation: The change of phase of a substance from a vapor to a liquid. This is the opposite of evaporation. The process of condensation releases energy; this energy is known as latent heat. Conduction: The transfer of heat energy through a solid. Convection: The transfer of heat energy through a liquid or gas due to the motion of that liquid or gas. Insight Training LLC Project Kill The Flashover 97 Crosshair (and spot temperature): The intersecting vertical and horizontal line superimposed on the thermal imager display. It is commonly used to indicate the approximate area from which a thermal imager is taking a surface temperature reading. A small “+” shape that aids in aiming a thermal imager for temperature measurements. This is also known as the spot temperature which is usually displayed in the lower right hand corner of the display. It is important to note that this is an approximate measurement of a defined area and NOT the entire image. Notice the spot temperature in the image to the right. It is obviously hotter than 87 degrees Fahrenheit but the TIC is measuring the temperature of the concrete wall of the burn building within the cross hairs. Degree: An increment of temperature measurement. Detector (Infrared): The individual chip or wafer that senses infrared energy. Diffuse Reflection: The random reflection from a rough surface, which results in a fuzzy scattered reflection. Insight Training LLC Project Kill The Flashover 98 Distance to Spot Ratio(or Spot Size Ratio SSR): A measurement of the area a pyrometer or radiometric thermal imager views from a specific distance. A 10:1 ratio indicates the surface temperature measurement taken at 10 feet is averaging an area of 1 square foot. Electromagnetic Radiation: The field effects given off by accelerating a charged particle in a magnetic field. Depending on field strength and speed of acceleration, many types of electromagnetic radiation are created. Electromagnetic Spectrum: A plot of the range of wavelengths and types of electromagnetic radiation found to exist from subsonic waves to cosmic rays. Radio waves, infrared energy and visible light are all portions of the spectrum. Emissivity, Emission: What is emissivity and why is it important to the proper use of a TIC? Emissivity is an objects ability to emit heat. Emissivity ratings are defined as fraction of energy (rated between zero and one) in comparison to a perfect black surface which has an emissivity value of 1. Insight Training LLC Project Kill The Flashover 99 A TIC detects thermal radiance from solid surfaces and from gases that radiate in the 8-14 um spectral range. Emissivity affects the radiation in a way that can make the surface or gas appear to be a temperature that is different than it actually is. In general surfaces that are black and rough in surface texture tend to have a high emissivity’s and surfaces that are shiny/smooth have lower emissivity’s. Emissivity is the single most important attribute necessary for thermal measurement. Fire Service TIC’s do not generally offer adjustable emissivity settings. The majority of TI manufacturers have the TIC preset at .95 which is the most common emissivity of materials made from carbon. As a general rule, any object that is shiny or reflective, will have a low emissivity and the temperature measurement displayed upon the TIC screen will be inaccurate (can be off by several hundred degrees in some cases). Energy: is the ability to do work (the application of force through distance). There are three types of energy that strike a thermal imaging detector: emitted, reflected, and transmitted. Engine: The core component of a thermal imager. This includes the FPA, the circuit boards that run the FPA, and the software that controls the FPA and interprets the signals to generate a thermal image. Equilibrium: A system is in equilibrium when its temperature properties are uniform and not changing with time. Insight Training LLC Project Kill The Flashover 100 Evaporation: The process whereby atoms or molecules in a liquid state gain sufficient energy to enter the gaseous state. This takes thermal energy and cools the surface where evaporation is occurring. This effect is noted when observing a structure from the exterior when winds are above 3 mph. This results in a 50 percent decrease in radiated energy observed through the IR camera. F-number (f/#): The ratio of focal length to aperture for a lens assembly. Smaller numbers represent faster lenses, which means that scene changes are conveyed to the detector more rapidly. Fahrenheit: A temperature measurement scale, in which Absolute Zero is - 459.7° F, water freezes at 32° F and water boils at 212° F. Far Infrared: The longest wavelength of infrared radiation, measured as roughly 8 to 14 microns. This is the range used by fire service thermal imagers. Also referred to as Long Wave Infrared. Ferroelectric: The physical property of a material that leads to thermal detection. This refers to the material’s ability to polarize as a direct result of temperature change. The stronger the relationship between temperature change and polarization, the better the material’s ability to function as a detector. The most common ferroelectric TIis BST-based. What does ferroelectric mean? A TIC’s detectors that are ferroelectric in nature detect heat by storing it as a value on each individual pixel. BST and pyroelectric vidicon tubes are examples of ferroelectric detectors Insight Training LLC Project Kill The Flashover 101 Field of View (FOV): The total field, measured as an angle, within which objects viewed by a thermal imager. Narrower FOVs generate more life-size images and distances, while wider FOVs place more image on the display. The most common FOV for fire service TIs is about 50°. • HFOV: Horizontal Field of View • VFOV: Vertical Field of View • IFOV: Instantaneous Field of View • MFOV: Measurable Field of View FORD: An acronym in thermography that states in order to have a good thermogram to analyze it must be in Focus, Range (proper temperature range), and Distance FPA (Focal Plane Array) The infrared detector itself, usually a thin wafer less than 1” square. The most common fire service FPAs are 320x240 pixels or 160x120 pixels. Higher resolution FPA’s are becoming available as high as 640x480. Frequency (or Frame Update Rate): The number of cycles an operation occupies per period of time. The normal unit of measurement for frequency is Hertz (Hz), or cycles per second. The human eye sees images at 27 Hertz. Any fire service Thermal Imager should therefore be at least 30 Hertz to avoid lag. This is also called “refresh rate” Refresh rate (or frame update rate) is the number of times per second that a new image is “created” by the sensor. The refresh rate is determined by mechanical attributes (eg. chopper wheel), where applicable, and the speed of the electronics. Insight Training LLC Project Kill The Flashover 102 Fusion: A mode that allows a TIC to perform picture in picture. This allows a thermogram and an optical in the same shot. This is an industrial application often used for inspections. Photo from FLIR Germanium: Why do TICs have a Germanium window on the front of the camera? The Germanium window allows thermal energy to transmit through it (unlike glass) and provides impact protection for the internal lens (also made of Germanium) that focuses the thermal image onto the detector’s focal plane array. In certain cases, the Germanium lens is coated with AR (an AntiReflective Coating) and excessive cleaning can remove the AR Coating causing more transmission loss and resulting in calibration error. Heat: The energy or sensation that humans associate with infrared radiation. Also known as the form of energy that is transferred by a difference in temperature. Heat Capacity: The amount of heat required to raise the temperature of a specific quantity of a substance by one degree. Heat Flux: the rate of heat energy transfer through a given surface per unit time. The SI derived unit of heat rate is joule per second, or watt. Heat flux density is the heat rate per unit area. This is commonly measured in failure ratings of firefighter PPE and measured in Kilowatts/meter squared. Heat Sink: A device for dissipating heat; it absorbs heat by conduction from heat producing devices and dissipates heat by means of convection. Heat sinks are common inside older fire service thermal imagers to help maintain proper operating temperatures. Insight Training LLC Project Kill The Flashover 103 Heat Transfer: The flow of thermal energy from one object to another, by means of conduction, convection or radiation and also condensation and evaporation. Also known has Heat Flux. Hertz (Hz): A unit for measuring frequency. One Hertz is one cycle per second. High Resolution: What makes a quality high resolution thermal imaging picture? Thermal imaging picture quality is determined by a number of factors: 1. The quality of the lens that focuses the thermal image onto the FPA. One measurement of lens speed is the f-number. The smaller the f-number, the wider the lens, and the better the image quality. Generally, the main constraints to lens quality include weight and size (the better the lens, the bigger and heavier it will be). 2. The number of pixels on the FPA. With all other thermal system components being equal, the more pixels on the FPA, the finer the image details that can be resolved. 3. Whether it’s micro bolometer or BST. BST pixels are mechanically interconnected, whereas micro bolometer pixels are mechanically isolated. The thermal energy seen by an individual BST pixel can therefore “bleed” onto nearby pixels, but isolated micro bolometer pixels sense independently and provide clearer, crisper image lines. 4. The electronic signal processing (video enhancement electronics). Most fire service thermal imaging cameras are controlled by microprocessors, which not only monitor the system but also “enhance” the thermal Insight Training LLC Project Kill The Flashover 104 image. For example, some cameras are able to generate near 320 x 240 FPA performance by using a 160 x 120 array and “averaging” to generate the remaining image points. Others are able to determine if a pixel is not functioning properly and approximate its correct output using surrounding pixels to generate a smoothed image. 5. The MRTD. (See definition) 6. The NETD. (See definition) 7. The Dynamic Range. (See definition) 8. The amount of system signal noise. Signal processing and components may add noise (or “snow”) to the image. The cleaner the system, the better the image (difficult to measure but easy to see). 9. The display used to interface with the user. The better-quality display provides a better image. Hot Spot Tracker/Cold Spot Tracker: A feature/option offered by Fire Service TIC manufacturers that is borrowed from Industrial applications where the IR camera seeks out the hottest/coldest pixel within the Field of View. Imager: A fully incorporated infrared detecting system that contains the detector, optics, processor, power source and display. Incident Radiant Power = Emitted Radiant Power + Transmitted Radiant Power + Reflected Radiant Power; Which is the total radiation going to an object. Insight Training LLC Project Kill The Flashover 105 Infrared (IR): electromagnetic radiation which occupies the band from 0.7 microns to 100 microns. infrared radiation is between the visible spectrum and microwave radiation. Infrared thermography: is the process of acquisition and analysis of thermal information from non-contact thermal imaging devices. Or in layman’s terms, it is the ability to detect heat off of a surface. Infrared-window: A protective cover, transparent to infrared radiation, placed on the front of a thermal imager to help protect the primary lens from damage. Many fire service thermal imagers use a germanium window. This is also a term used in industry known as an IR window for inspection purposes. Many industrial machines and components will have an IR window were a thermographer can inspect those components without opening up the machine or electrical panel. Isotherm: The isotherm is the oldest of the measurement tools, appearing in the earliest measurement cameras from the 1960’s. An isotherm is a measurement tool highlighting the same areas of the same thermal radiation intensity. In fire service applications, this is found in the Bullard TIC with the Thermal Throttle, Drager UCF 9000, and FLIR K55-65 series. Kelvin: The temperature scale used by scientists. The scale is based on the Celsius scale increments, but 0° is Absolute Zero rather than the freezing point of water. LCD (Liquid Crystal Display): A flat panel display system, common on many modern thermal imagers. Lens: An optical component constructed of transparent substance with one or two curved surfaces of different curvature that has the ability to change the Insight Training LLC Project Kill The Flashover 106 direction of beam travel. Infrared lenses are used for focusing the detector at a distance of interest and for modifying the size and distance of the focused field of interest. Light: The region of the electromagnetic spectrum which is visible to the human eye. This is usually considered the region from 0.39 (violet) to 0.77 (red) microns. Long Wave Infrared (LWIR): The longest wavelength of infrared radiation, measured as roughly 8 to 14 microns. This is the range used by fire service thermal imagers. Also referred to as Far Infrared. Micro bolometer: A type of infrared detector that is capable of measuring absolute energy levels on each pixel of the FPA. Surface temperature measurement can be done directly from a micro bolometer’s FPA. Uncooled Micro bolometer: A micro bolometer is a specific type of bolometer used as a detector in a thermal camera. Infrared radiation with wavelengths between 7.5-14 µm strikes the detector material, heating it, and thus changing its electrical resistance. This resistance change is measured and processed into temperatures which can be used to create an image. Unlike other types of infrared detecting equipment, micro bolometers do not require cooling. A micro bolometer is the latest type of thermal imaging FPA, which consists of materials that measure heat by changing resistance at each pixel. The most common micro bolometer material is vanadium oxide (VOx). Amorphous silicon (ASi) is another relatively new micro bolometer material. In addition, the ASi model has poor dynamic range and isothermal scene performance which limits the current version(s) for many fire service applications. Although micro bolometers do not require a chopper to refresh the image, they must occasionally be recalibrated for the pixels to provide a consistent output and to Insight Training LLC Project Kill The Flashover 107 avoid oversaturation. The device that occasionally (every 30 seconds to 5 minutes) and automatically recalibrates the FPA is called a “shutter” Micron (micrometer): A metric measurement equal to one-millionth of a meter. Mid Infrared (or Mid-wave Infrared, MWIR): Infrared radiation with wavelengths of roughly 3 to 5 microns. MWIR infrared camera’s detect up to 90% of the radiation in the atmosphere. Minimum Resolvable Temperature Difference (MRTD) This number expresses the sensitivity of an infrared detector. It defines the smallest temperature difference the detector can differentiate. The lower the number, the more sensitive the unit is. Units with high levels of sensitivity (lower MRTD) tend to produce better, more defined images, especially in bland scenes. Near Infrared: The shortest wavelength infrared radiation, measuring approximately 1 to 3 microns. This is also referred to as Short Wave Infrared. (more common in military applications) NETD (Noise Equivalent Temperature Difference) This is a technical measure of sensitivity for a thermal imager, similar to the MRTD. Generally, a lower NETD will equate to more usable images, especially in bland scenes. What does Sensitivity (NETD) mean when applied to a Thermal Imager? Sensitivity expresses the ability of an infrared camera to display a very good image even if the thermal contrast in a scene is low. Put another way, a camera with good sensitivity can distinguish objects in a scene that have very little temperature difference between them. Insight Training LLC Project Kill The Flashover 108 Sensitivity is most often measured by a parameter called Noise Equivalent Temperature Difference or NETD, for example, NETD @ 30 C : 80mK. A Kelvin degree is the SI base unit of thermodynamic temperature equal in magnitude to a degree Celsius, so mK means thousandths of a degree (80mK = 0.080 K). ASTM E1543-00 Standard Test Method for Noise Equivalent Temperature Difference of Thermal Imaging Systems . Non-Contact Surface Measurement: A thermal imager uses remote sensing by detecting IR energy from a target without actually having to intrude upon or affect the target. In many cases the components are hazardous to touch. NUC (Non-Uniformity Correction) this is where the TIC corrects minor detector drift that occurs as the scene and environment change. It is normal to hear a click and the image may freeze momentarily. The Camera will perform a NUC on its own when needed from every 30 seconds to up to several minutes. It will initially happen at shorter intervals when the TIC is first powered up. Operating Temperature Range The acceptable temperature range for an infrared detector to remain calibrated and function properly. This refers to the temperature of the detector itself, not the ambient environment. The use of heat sinks, insulation and construction will affect how well a detector stays in its operating range, especially in a fire environment. Properly designed fire service thermal imagers will have other components that have a similar operating range as the detector. Pixel (Picture element) The smallest location size on a display or in memory. FPAs are measured in pixels, with each pixel generating a small portion of the thermal image. Insight Training LLC Project Kill The Flashover 109 Pyrometer An instrument used for non-contact measurement of surface temperatures. BST-based thermal imagers with temperature measurement have a pyrometer interlaced with the infrared detector. Qualification: comprises demonstrated skill, demonstrated knowledge, documented training, and documented experience. Reverse Polarity: A filter/color palette option that is designed for industrial applications in which it makes all target items that are hot appear black/cold. There are a few fire service TIC’s that offer this feature. This is not a recommended feature for firefighting. Radiation: Heat transfer of energy in the form of electromagnetic waves. Forms of radiation include cosmic rays, gamma rays, x-rays, ultraviolet radiation, infrared, visible light, radio, audio and subsonic. Radiometric: The ability of an infrared detector to measure, pixel by pixel, the actual scene temperature and display the results. Micro bolometers can be radiometric. This is important to note if the TIC can store a radiometric image versus a Jpeg image. A radiometric image can be analyzed pixel by pixel for temperature measurements by a trained professional. Reflectance (Reflectivity): The amount of total infrared radiation reflected by a surface. This value is frequently the inverse of the Absorption (Emissivity). Saturation: The point at which an FPA or pixel cannot register any more infrared radiation. Saturated pixels will automatically be displayed as the hottest indicator (white, red, etc.) on the system. Also defined as the condition in which a further increase in infrared radiation produces no further increase in the displayed image. Insight Training LLC Project Kill The Flashover 110 Sensitivity: A measure of the minimum amplitude of input signal change to which an instrument will respond. On a thermal imager, this is a measurement of the smallest temperature differences the unit will detect. Sensor: The component that converts radiation into electrical signals. This can refer to the detector itself, the engine or the entire thermal imager. Thermal Imaging Camera Sensor Materials: Amorphous Silicon: Amorphous silicon (ASi) is another relatively new microbolometer material. In addition, the ASi model has poor dynamic range and isothermal scene performance which limits the current version(s) for many fire service applications. Vanadium Oxide: Vanadium oxide thin films may also be integrated into the CMOS fabrication process although not as easily as a-Si for temperature reasons. VO is an older technology than a-Si, and for these reasons its performance and longevity are less. Deposition at high temperatures and performing post-annealing allows for the production of films with superior properties although acceptable films can still be made subsequently fulfilling the temperature requirements. VO2 has low resistance but undergoes a metalinsulator phase change near 67 °C and also has a lower value of TCR. On the other hand, V2O5 exhibits high resistance and also high TCR. Many phases of VOx exist although it seems that x≈1.8 has become the most popular for micro bolometer applications. BST: BST stands for “barium strontium titanate,” and this type of detector was developed by Raytheon Corporation. It is a ceramic-like thermal energy sensing material is used to make BST focal plane arrays, which measure heat by storing it as a fixed value (similar to a capacitor) at each pixel. When the grid of pixels, or focal plane array, is monitored simultaneously, a thermal image is Insight Training LLC Project Kill The Flashover 111 generated. Because of their fixed-image properties, BST pixels must be refreshed regularly in order to maintain the perception of real-time imaging. BST isn’t widely used anymore because of: • The size of the sensor (too large) • Could not incorporate color • White Out Short Wave Infrared (SWIR): The shortest wavelength infrared radiation, measuring approximately 1 to 3 microns. This is also referred to as near infrared. Shutter: A small device that repeatedly obstructs the FPA in a micro bolometer thermal imager. The shutter covers the FPA, stopping all infrared energy from reaching the FPA. During the period the FPA is covered, the thermal imager verifies its calibrations. When this occurs, the image on the display will freeze momentarily. All micro bolometers have a shutter. A shutter is a mechanical device, generally shaped like a flag, which closes in front of the detector to activate the calibration for a uniform temperature (or black body). This automatic, periodic calibration is necessary because pixels in micro bolometers drift and cause image degradation. This is also known as NUC’ing (Non-Uniformity Correction) where the TIC corrects minor detector drift that occurs as the scene and environment change. It is normal to hear a click and the image may freeze momentarily. The Camera will perform a NUC on it’s own when needed from every 30 seconds to up to several minutes. It will initially happen at shorter intervals when the TIC is first powered up. Spatial Resolution: the clarity or fineness of detail attained by an infrared camera in producing an image. This can also be expressed as DPI or dots per inch, pixels per line, or lines per millimeter. Thus, it is a measurement of how detailed or fine an image is. Insight Training LLC Project Kill The Flashover 112 Spectral Response (What range of light the TIC actually sees): Thermal imaging sensors are designed to detect long-wave infrared radiation between 8 to 14 microns. This energy, unlike visible light, can pass through smoke and is undetected by the naked eye. There are LWIR detectors and SWIR detectors. SWIR: See Short Wave Infrared. Temperature: An expression of thermal energy density, or how hot or cold an object is. It is also stated as a measurement of the average kinetic energy of the molecules in an object in a system. Temperature Range: The maximum to minimum temperature display capability of a system. This can be affected by the FPA, the engine’s software program or manufacturer’s selection. Thermal Radiation: Electromagnetic energy whose natural wavelength fall between .7 and 100 microns, also called infraredradiation. Thermistor: A device which measures temperature. The sensor for the thermistor is a semi-conducting resister whose resistance changes significantly with temperature. Thermocouple: A device that measures temperature through conduction. The device reads temperature difference by measuring the difference in potential generated at the junction of two dissimilar metals. Thermoelectric Cooling: A solid-state device that converts current into a temperature difference between two junctions. It is possible to put thermoelectric junctions in series or parallel to increase either the overall temperature drop or their power. Insight Training LLC Project Kill The Flashover 113 Thermography: The study of remote temperature measurement. Thermoplastic: A general term used to describe a plastic that will hold up to high temperatures. TI (Thermal Imager): A packaged, independently powered unit that detects infrared radiation and portrays that information on a video display for the user to interpret. TIC (Thermal Imaging Camera)See TI. Transmittance (Transmissivity) A measurement of the ability of a material to pass radiation from one side to the other without absorbing or reflecting it. Infrared transmittance for most materials is near zero. Therefore, absorption/emissivity and reflectivity are usually inverse values. Vanadium Oxide: A material used to create infrared detectors. These types of detectors are used in a number of fire service thermal imagers. Wavelength: The distance between the two peaks of an energy wave cycle. Very long wavelengths may be measured in Hertz, or how frequently the peaks occur per second. White Out (or Over-Saturation): A condition that afflicted older infrared detectors (vidicon tube technology) . When the detector was exposed to strong infrared sources, such as fires, the thermal imager would generate completely white images on the display. Sometimes this was intentional in an effort to protect the detector from Insight Training LLC Project Kill The Flashover 114 damage; sometimes it indicated damage to the detector. Modern thermal imagers do not white out; they may experience saturation. White-out or oversaturation occurs when a thermal imaging detector is subjected to too much thermal energy, and the image, which appears as a white cloud, no longer identifies fine details in the scene. Most thermal imaging cameras have an automatic iris or appropriate software to adjust system controls to avoid white-out immediately after intense thermal energy hits the detector. Pointing the TIC directly at superheated sources, such as the sun, is not recommended and may damage the detector. If experiences “white out” it is often due to condensation on the lens. The TIC cannot see moisture so it appears white on the screen. Simply wiping the lens will resolve the issue.