The fundamentals of PyroLance technology have been known to the fire service for almost 150 years, according to Cas Seyffert, PyroLance VP of Operations. He quotes an 1866 statement made by James Braidwood, chief fire officer of the London Fire Brigade. “The men of the fire brigade were taught to prevent, as much as possible, the access of air to the burning materials. What the open door of the ash-pit is to the furnace of a steam boiler, the open street door is to the house on fire. In both cases, the door gives vital air to the flames.”
Let’s start with water. Water possesses the greatest practical specific heat capacity of all naturally occurring substances and has the greatest latent heat of vaporization of all liquids. The latent heat of vaporization is the amount of heat required to change a liquid into a vapor without a change in temperature.
Ultra-high pressure water mist systems operate on the principle of generating very fine droplets of water and delivering them to the fire zone.
The advantage of this is that water mist can be very effective at fire suppression due to its high specific heat and heat of vaporization coupled with the increased surface area allowing faster heat absorption.
When discussing water mist systems, often the immediate interest is in the droplet size of the water particles being produced as this factor greatly effects how the spray will interact with the fire and which of the extinguishment mechanisms listed above will play significant roles.
The size of water particles plays an important part in the characteristics and interaction with a fire. In the case of heat extraction, smaller particles result in a higher surface area and hence faster heat extraction for a given volume.
One of the most profound characteristics of ultra-high pressure (UHP) water mist involves the ability of the mist to suspend itself in the atmosphere. Hang time is the falling rate of a particle as it passes through the plume. As a particle becomes smaller, the drag force created across its surface becomes larger in relation to its mass and hence the gravitational force on it. Hence a large particle will fall quickly to the floor while a small particle will fall at a much slower rate. This is easily verified when using a conventional nozzle next to an UHP nozzle. Opening and closing the bail quickly, on both, will illustrate the difference in hang time.
Most methods of interior fire attack focus on “putting wet stuff on the red stuff.” The designers of the PyroLance piercing attack technology are more concerned about ventilation control, cooling the superheated gases, and controlling the thermal layer.
“Taking control of those products of combustion gives firefighters instant command of the fire,” according to Seyffert, “You eliminate the risk of firefighters being caught in a flashover or backdraft.”
There is rising concern by many fire chiefs that the rate of fire growth, in the structural environment, has changed dramatically over the past few years leading to accelerated fire growth that is endangering firefighters. The HRR (Heat Release Rate) of new synthetic materials is largely to blame for this extremely dangerous situation and this factor is not always taken into consideration when initiating an aggressive interior attack.
This has been demonstrated in recent fires where firefighters were caught by rapid fire growth soon after entering these extremely dangerous environments.
Excellent studies have recently been completed by NIST, as well as ATF, on fire flows within a structure and demonstrating the importance of ventilation control, the crucial aspect of thermal layer control, and the necessity to pre-cool fire gases prior to entry.
This technique, known as “Transitional Fire Attack” is rapidly developing momentum and involves gaining a margin of control, over interior fire conditions, by precooling the thermal layer prior to committing firefighters to an aggressive interior attack.
The PyroLance technology lends itself to this form of fire attack. Water can be applied from an exterior defensive position to the interior of the fire zone without ever putting a firefighter at risk. This is achieved using abrasive cutting technology to penetrate the exterior wall of the structure, in seconds, and flowing ultra-high pressure mist directly into the thermal layer through a 1/8 inch hole. This leads to a rapid cool down of the interior, without the introduction of any oxygen, allowing firefighters to gain control of the fire prior to entering the structure to commence interior operations.
PyroLance achieves this by flowing water at 10 gpm, at a pressure of 1500 psi, with a speed of 160 mph, through a specially designed PyroLance penetrating nozzle that enables it to add a granite abrasive, into the high pressure stream, allowing it to pierce, or cut, most materials at a phenomenal rate. The PyroLance is supplied by a ¾-inch high pressure hose, with a maximum length of up to 1,000 feet from the ultra-high pressure fire pump. The hose is typically stored on an electrically operated hose reel, or multiple hose reels, allowing rapid deployment.
The Greater Manchester Fire Department, in the United Kingdom, has just placed piercing technology on their first out apparatus to facilitate the concept of “Transitional Fire Attack.” Their strategy is aimed at achieving a marked improvement in firefighter safety.
PyroLance technology is also effective on Class B fires. In recent tests at the Dallas-Fort Worth International Airport, Fire Training Research Center, a PyroBlitz attack nozzle, flowing 20 gpm at 1500 psi, was used on an open pit fire. Fuel used was E3 and the pit was 1,250 square feet in area. Using Williams Thunderstorm ATC (1 x 3) at 3 percent, the fire was extinguished in 45 seconds using less than 20 gallons of water. One participating firefighter commented “that this same fire is normally tackled using a 90 gpm nozzle and extinguishment is never achieved as fast as he witnessed” using the PyroBlitz attack nozzle.
Numerous applications have been identified, in the industrial fire protection sector, including the petrochemical and oil and gas industries. PyroLance applications include interior “fire in the box” scenarios, including furnaces, boilers, incinerators, reactor columns, scrubbers, filter houses, cable passages and other enclosed environments where conventional access methods do not accommodate the safe or effective placement of hand lines or master streams.
Domestically, current users of the PyroLance technology include the U.S. Air Force (210 units), U.S. Navy (9 units), the Mojave Air and Space Port, Area 51 and Dallas-Fort Worth International Airport (3 units). Recently the City of Houston Fire Department ordered a PyroLance unit. Internationally, PyroLance units are in service on the Panama Canal, Dubai Port World Sokhna and Petro Rabigh in Saudi Arabia among many others.
UHP technology and delivery systems have come of age. Application techniques and methodology have been vastly improved to eliminate so many myths associated with this type of application.
If you are looking for quick, efficient, hard hitting, fire fighting technology, that is easy to operate, it would be well worth it to take a look at PyroLance.
PyroLance’s primary goal is to create a safer environment for firefighters around the world.
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