Ultra-High Pressure Firefighting: The Fastest Attack New technology is no stranger to the fire service. Consider our protective gear, SCBA, PPV, thermal imaging cameras, water additives, automatic proportioning systems and CAFS to name just a few. Ultrahigh pressure (UHP) firefighting is yet another new revolutionary technology that will forever change the way we fight fires. One of the best tools on the market for taking advantage of UHP is the PyroLance. This unique system installs in any fire vehicle to allow firefighters to gain access to interior fires by blasting a 3 mm hole through any wall, roof or other type of barrier. Once a barrier is penetrated, the PyroLance continues to shoot a UHP water fog to aggressively attack the gaseous phase of the fire. This effectively knocks down the fire and rapidly cools the environment, thereby allowing for a safe entry to conduct search and rescue as well as overhaul operations. Let s take a closer look at how PyroLance is changing firefighting by using ultra-high pressure to pierce barriers, then rapidly cool and extinguish fires at their source. THE BACKGROUND Traditionally, we have always attacked the fuel phase of the fire. Several years ago, researchers in Sweden began experimenting with flashover simulators and the gaseous phase of fire behavior. What the researchers discovered was that by flowing an ultra-high pressure water fog into a fire s thermal layer, they were able to inert the fire gases without introducing oxygen. As a result, the interior heat dropped significantly in a matter of seconds. With the fire controlled, the risk of flashover eliminated and the temperature reduced to a safe level, crews could now make a safe entry into the fire area. Subsequently, other groups have conducted their own research to evaluate the cooling and suppression capabilities of UHP. All had similar findings.
UHP THEORY Up to this point, the industry has not formally defined what ultra-high pressure is with respect to mobile firefighting applications. For this discussion, we will use the following definitions: Normal Pressure: Under 500 PSI (<35 Bar) High Pressure: 500 to 1,000 PSI (35 to 70 Bar) Ultra-High Pressure: Over 1,000 PSI (>70 Bar) The second point we need to understand is water droplet size. Water droplets are typically measured in microns. A micron (µ or m) is one millionth of a meter (0.001 mm) or 1/25,400 inches. A micron is also referred to as a micro meter. Generally, water droplets flowing from a Normal Pressure hand line range in size from 700 to 1,000 µ. By contrast, the droplet size flowing from a UHP line will typically fall in the range of 80 150 µ. For a given volume of water, therefore, the surface area of UHP droplets is significantly greater than for Normal Pressure droplets. This greater surface area enables faster and more efficient cooling. Oil Fog Smoke Optimum UHP droplet size Typical Normal Pressure droplet Sea Fog Mist size Rain Clouds Drizzle 0.1 1.0 10 100 1000 Aerosols Nozzles Sprinklers Fine Sprays The smaller droplet size found in UHP streams tend to have a greater hang time in the air, thus enabling the water to better saturate the air and increase the humidity. This effect can readily be seen in a side-by-side comparison using a Normal Pressure hand line and a UHP hand line. When you point both streams up in the air and then simultaneously close both nozzles, the UHP water fog will hang in the air much longer than the Normal Pressure droplets. We know if we can build the humidity to 30%, combustion ceases. The additional hang time of UHP coupled with the smaller UHP droplet size make this possible. In theory, with greater surface area and a longer hang time we would expect UHP streams to outperform Normal Pressure streams. In fact, that is exactly what the tests demonstrate. 2
THE EMPIRICAL EVIDENCE Since the early 1980s, the U.S. Air Force has relied on the Model P-19 as their first response ARFF vehicle. The drawback with this apparatus is that only one vehicle can fit into the cargo area of a C-130 aircraft. In the early 2000s, the U.S. Air Force began looking for technologies that could provide as much or more punch as the P-19, only on a smaller platform. Their ultimate goal was to carry two of the replacement vehicles on a C-130 aircraft. The U.S. Air Force Research Lab conducted extensive testing involving UHP technology in 2006-07. They ran over 100 tests comparing a UHP-equipped P-19 vehicle flowing 300 GPM (1135 LPM) to a Normal Pressure P-19 flowing 700 GPM (2650 LPM). Some of the video footage of those tests are available on the PyroLance website at www.pyrolance.com and the complete AFRL report is available at www.aviationfirejournal.com/pdf/uhpp-19finalreport[1].pdf. The goal of the tests was to obtain equal or greater punch on a smaller platform. The video footage on the PyroLance website shows side-by-side attacks on similar pit fires by the two test vehicles. The results are typical for the findings and conclusions of the AFRL report: UHP P-19 Normal Pressure P-19 Time To Knockdown: 31 seconds 43 seconds Total Water Consumed: 151 Gallons 525 Gallons (572 Liters) (1987 Liters) These results show UHP knocking down a fire with less than 29% of the water in 72% of the time than with Normal Pressure on a similar fire! UHP vs. Normal Pressure testing has shown similar results on wildland and structural fires. The following chart illustrates the findings for UHP vs. Normal Pressure in wildland, hydrocarbon and structural applications: Water Usage Comparison Wildland Fuel Structural Fire Fire Fire NORMAL PRESSURE ULTRA HIGH PRESSURE (UHP) The AFRL study also concluded the following: Optimum Droplet Size: 90-100 m Optimum Droplet Velocity: 125-150 m/s UHP provided faster knockdown than Normal Pressure UHP required less water than Normal Pressure UHP required less water additives than Normal Pressure 3
UHP THE PRACTICAL APPLICATION When a droplet from a Normal Pressure water stream enters a fire area, it has the potential to convert all of its mass to steam. In reality, only about 10% of that mass will convert to steam and cool the fire. When a droplet from a UHP water stream enters a fire area, that droplet will convert about 90% of its mass to steam. This explains the significant difference in efficiency between the two streams. Together, the smaller UHP droplets comprise more surface area than Normal Pressure water droplets. This is why they have the ability to cool more efficiently. So, let s compare a 100 GPM (380 LPM) Normal Pressure hand line at 10% efficiency with a 20 GPM (76 LPM) UHP hand line with 90% efficiency. The total volume of water flowed by the two streams over time is illustrated in the following chart. Total Water Flowed in Minutes (Gallons / Liters) Normal Pressure UHP 1,000 / 3,800 2,000 / 7,600 200 / 760 400 / 1,520 3,000 / 11,400 600 / 2,280 4,000 / 15,200 800 / 3,040 5,000 / 19,000 1,000 / 3,800 6,000 / 22,800 1,200 / 4,560 0 10 20 30 40 50 60 The volume of water for the Normal Pressure stream exceeds the UHP stream by a factor of five. Now let s compare the volume of water in the two streams that is actually cooling. Remember, the efficiency for the Normal Pressure stream is 10% while the efficiency of the UHP stream is 90%. The comparison looks like this: Effective Water Flowed in Minutes (Gallons / Liters) Normal Pressure UHP 180 / 684 360 / 1,368 200 / 760 540 / 2,052 300 / 1,140 720 / 2,736 400 / 1,520 900 / 3,420 500 / 1,900 1,080 / 4,104 600 / 2,280 100 / 380 0 10 20 30 40 50 60 4
What we can see from this example is that while the Normal Pressure stream flowed five times the volume of water as the UHP stream, the UHP stream actually outperformed the Normal Pressure stream by 80%. This can be a significant advantage when one considers the resources (both equipment and manpower) required to flow the added volume of water, the weight of the added water on a structure and the subsequent water damage to that structure due to the added water volume. We discussed the improved efficiency of UHP, but now let s also look at some of the additional benefits that should be considered by anyone investigating UHP technology: Safety Ergonomic 60-85 (18-26 m) throw range Ease of use Immediate knockdown Reduced weight Hydraulic ventilation Quick in-service and take-up time Environmental Design 90% water efficiency Compact less weight to carry Less water runoff Small installation footprint Less damage Easy to customize A number of manufacturers are now marketing UHP technology for attacking and cooling. However, there is another side of UHP technology, proprietary to PyroLance, which enables fire crews to punch through virtually any material in a matter of seconds. PENETRATING WITH UHP PyroLance perfected and patented the technology to penetrate walls and other barriers by flowing water at 10 GPM (38 LPM) with a pressure of 1,500 PSI (100 BAR) at speeds of 400 MPH (650 KPH) through a specially designed lance that integrates granite abrasive. This combination allows firefighters to pierce or cut virtually any material at a phenomenal rate. Once a barrier is penetrated, the operator continues to use the lance to inject UHP water fog into the thermal layer of the fire area. The UHP water fog shot through the lance can reach as much as 35-40 (10m- 12m), with a heat absorption capacity in excess of 6,000 BTU/sec. And the lance does this while allowing fire crews to operate from a safe exterior position! This explains why UHP firefighting is such a paradigm shift from the way fire crews have traditionally operated. Working with the PyroLance system is more efficient, more effective and safer than Normal Pressure. 5
In a series of tests conducted in Oklahoma City, fire was started and allowed to burn in a second story apartment until the interior temperature reached 1,380 F (750 C). (Video footage of this burn can be seen on the PyroLance website at www.pyrolance.com.) Crews entered the first floor of the structure, penetrated the first floor ceiling using the PyroLance s mix of UHP and granite abrasive, and then continued to flow UHP water fog into the second story apartment. From the time crews water flowing, it took only 2:00 minutes to bring the interior temperature of the second story apartment to 212 F (100 C). It is important to note, crews were never exposed to extreme heat or the risk of a flashover in utilizing this new technology! These same tactics can also be employed when penetrating and attacking a roof or attic space from the safety of an aerial bucket or ground ladder; a basement fire from the safety of an exterior position; or any type of vehicle, aircraft, train car, or ship compartment fire. The Oklahoma City tests concluded that the PyroLance offered the following advantages: Improved firefighter safety o Indirect attack o Reduced stress o Lighter hose o Non-sparking penetration Faster cooling Reduced damage Improved visibility Less water additives Preserved evidence for arson investigation The main components of the PyroLance technology consist of a UHP pump, abrasive tank, hose reel and penetrating lance. A gas or diesel engine, PTO or hydraulic motor can power the pump. The system is available with a wireless lance that s controlled by the operator or in manual version Water Tank Abrasive Tank UHP Pump Hose Reel Control Panel Piercing Lance with Wireless Transmitter controlled at the pump panel. At right is a standard configuration. The base unit (shown at left) is compact and easily installed in a compartment or on a skid unit. The typical dimension is 36 W x 24 D x 32 H (914 mm x 610 mm x 813 mm). The system is available with Lance only, Blitz only or in a combined Lance/Blitz configuration. The lance has numerous features, including a collapsible stock and adjustable fore end grip to accommodate different sized firefighters. The fore end grip doubles as a stand when the lance is not in use. The wireless version of the lance comes with a folding antenna, safety lock on the trigger, abrasive on/off switch with indicator light, and a low battery indicator. 6
About PyroLance PyroLance is a revolutionary firefighting tool used by fire units around the world. By integrating granite abrasive with an ultra-high pressure (UHP) stream of water, PyroLance allows fire crews to pierce through concrete, composites, plate steel and other barriers from a safe position, and then cooling the hot gases and attacking the fuel sources of a fire with a powerful UHP mist. For more information about UHP firefighting and the PyroLance operating system, visit www.pyrolance.com, email sales@pyrolance.com or call +1 (303) 766-1137. 2012 PyroLance LLC. All Rights Reserved. 525 Main Street Box 120609 New Brighton, MN 55112 USA +1 303.766.1137 pyrolance.com 7