|Carl J. Haddon|
I’ve been asked the question, “How does the topic of encapsulator agent correlate with the column title ‘To the Rescue’?” Great question, easy answer.
Webster’s Dictionary and Google define “rescue” as “coming to the aid of; save from imminent danger or imminent harm.” Technical rescue equipment and apparatus are typically what come to mind when you see my column title. Read on while I explore the possibility of changing the title of this column … or not.
Those we are sworn to serve are not the only ones who need rescue. The nature of our chosen profession puts us in harm’s way and imminent danger at every turn. With the new and increasing dangers, threats, and especially cancers facing fire, rescue, and emergency medical service personnel daily, I have chosen to seek out new and innovative products and equipment that not only can help those we respond to but also can help minimize threats to our (emergency responders’) health and well-being. I hope to showcase these goods and services here in my column. This is the first installment.
Electrical transformer explosions and fires are nothing new. Solar panel arrays and solar panel covered rooftops (especially commercial) are becoming more and more common across the country. Fires involving (always energized) solar panels are also on the rise. The average age of electrical transformers in the United States is 40 years old. Have you ever really looked to see just how many transformers exist in your response area? Because of age and degradation, we are seeing more and more of them catastrophically fail with resultant fires. These fires are typically difficult to fight because of the extremely high temperature of the spewing, burning, heavy oil inside the transformer and the very high temperature of the metal encasing the oil. Remember, too, that when the oil inside the transformer catches fire, it expands, causing a spewing and flowing (three-dimensional) fuel fire. This is to say nothing of the fact that it may or may not be energized. The good news is that you can (usually) have the power to these transformers cut. The problem is that sometimes it takes a while to get that power cut. Until now, these fires would often take hours and hours to fight.
Unlike electrical transformers, solar panels are 100 percent live 100 percent of the time. Basically, if light (most any light) is reaching solar panel cells, they should be considered and treated as energized. These panels often now feed lithium ion battery banks (the subject of a whole other article), which pose a new and VERY challenging firefight. With the aforementioned hazards and makeup of these fires, it has been proven that water, foam, and dry chemical extinguishing agents are most often ineffective and often contraindicated because of the presence of electrical current feedback potential.
Unlike these other extinguishment tools, (real) encapsulator agents form a cocoon around the water molecules (spherical micelles), which allows the agent to contact the heat source first, thereby “insulating” the water molecules from both heat and (under approved conditions) electricity. In other words, this technology allows for super rapid cooling of the oil and metal by way of “thermal conveyance” as opposed to plain water’s steam conversion. This rapid cooling allows for lowering the autoignition temperature of the heat source. Additionally, because of the polarity of the encapsulator agent’s molecular structure, the agent solution (3 percent) “encapsulates” the hydrocarbon fuel of the mineral oil in the transformer, rendering it inert and inflammable. Simply stated, this technology extinguishes these fires by rapidly lowering autoignition temperatures and by breaking the free radical chain reaction in the fire tetrahedron. It also provides permanent burn-back resistance through encapsulation.
The Proof Is in The Pudding
I know what you’re thinking: This is too good to be true. Fortunately, the Fire Department of New York (FDNY) and ConEdison did some of the heavy lifting for us.
Case Study, New York, New York, July 24, 2009, Queens Box 33-6334. Much has been written about this transformer fire in Queens. For the purposes of this article, the important information is simply that having deployed all the relevant resources at its disposal (engines, aerials, Purple K truck, foam trucks, etc.), none of the FDNY’s conventional resources could extinguish this fire until it introduced an encapsulator agent that the department was testing. This encapsulator was inducted at 3 percent, flowed through standard nozzles (as opposed to foam nozzles), and applied like water. Initial fire knockdown occurred in less than three minutes of applying the encapsulator solution.
For those interested, this box alarm can be easily found online. The FDNY continued to test encapsulator technology, which it still employs today. It also went so far as to work with ConEdison to test using an encapsulator agent on charged high-voltage electrical components. This testing revealed that the encapsulator agent it chose can be used by the FDNY under its prescribed protocol on electrified components without harmful electrical current feedback through the stream to the nozzle.
ConEdison points out the following:
Energized Fires: You cannot extinguish an energized transformer fire. If the transformer is arcing, presents with blue flame, or has the electrical arcing sound, members should take cover and consider the bomb concept: If you can see it, it can see you. Crews cannot solve this issue and will require utility intervention to isolate the electric source prior to operating at the scene.
Class B/C Fires: In the absence of sustained arcing, the fire officer will be managing a class B fire in a class C environment.
Overspray: Although the transformer is deenergized, what if the surrounding energized bus or equipment is hit by a stream as a result of overspray or wind influence? ConEd’s testing helped determine safe standoff distances for both fog and straight streams.
Solid Stream/Fog: Solid streams keep firefighters the farthest from the fire but are the most conductive. Fog is the least conductive but places firefighters closer to the problem. Overall, ConEd suggests selecting fog because the small droplets are less conductive, provide greater cooling, and have limited runoff.
ConEd considered every appliance/pattern or apparatus that could be used to determine if they would influence conductivity. With solid streams as firefighters approach the energized target, current rise back to the nozzle is not linear – it’s exponential. You can go from nondetect current to high-current return to the nozzle within a few feet.
All of this good information begs the question: If this case study happened in 2009, why are we just hearing about this technology now? The truth is that this technology has been around since the late 1990s – I have used an encapsulator since 1998. Encapsulators have been, and continue to be, widely used throughout other parts of the world. Unfortunately, the National Fire Protection Association (NFPA) did not recognize encapsulator technology until 2011. To that end, we now have NFPA 18A, Standard on Water Additives for Fire Control and Vapor Mitigation, which addresses water additives such as (true) encapsulator agents.
The popularity of encapsulator agents and this technology continues to grow with fire departments throughout the United States because, in no small part, of its added benefit of drastically reducing cancer-causing toxins found in soot and smoke while also greatly reducing heat stress on attack personnel.
Introducing new technology that helps reduce the number of us who wind up with job-related cancer, trying to reduce the number of us who experience heat stress-related cardiac emergencies, and trying to reduce line-of-duty deaths is a true “rescue” mission statement for this column, “To the Rescue.”
CARL J. HADDON is a member of the Fire Apparatus & Emergency Equipment editorial advisory board and the director of Five Star Fire Training LLC, which is sponsored, in part, by Volvo North America. He served as assistant chief and fire commissioner for the North Fork (ID) Fire Department and is a career veteran of more than 25 years in the fire and EMS services in southern California. He is a certified Level 2 fire instructor and an ISFSI member and teaches Five Star Auto Extrication and NFPA 610 classes across the country.