|The Elkhart Brass Solid Strike is a solid stream nozzle that allows the firefighter to vary gallons per minute or reach without shutting down to change tip size.|
|Firefighters use a Task Force Tips Mid-Force dual pressure automatic combination nozzle to extinguish a structure fire.|
A nozzle sits at the business end of every fire attack line, and choosing the type of nozzle to be used depends on a number of factors.
Considerations include the kind of fire, the water flow desired, the personnel available, and strategic and tactical considerations, such as whether the firefighter at the nozzle or the pump operator has control of the flow.
Among the four major categories of nozzles – solid stream, fixed gallonage, variable gallonage and automatic – manufacturers offer hundreds of models and types. There are even customized nozzles for departments prepared to pay the price. Each of those products is tailored to effectively perform essential functions – controlling the flow of water or foam, giving reach to get to the fire from a safe distance, and shaping the flow for maximum effectiveness.
Paul Albinger, director of sales at Elkhart Brass Manufacturing Co., said the key to nozzle manufacture is simplicity.
“The easier we can make nozzles work, the easier it is for firefighters to do their job,” he said. “In larger cities in the U.S., we’re seeing movement toward fixed-flow nozzles that provide a prescribed gallonage at a certain pressure, mainly for simplicity because of the ease of operation and to avoid confusion.”
Albinger said he’s seen similar interest in simplicity from smaller departments, but thinks they often have a greater need for flexibility to obtain a range of different flows.
“While a big city might have plenty of water all the time through a hydrant system, that’s not always the case elsewhere,” he said. “So other agencies might use an automatic or variable-flow nozzle for its variety of uses, from fighting structure fires to lesser flows such as car and brush fires, and even as a foam eductor.”
For instance, he said, a city department might want to flow 150 gallons per minute (gpm) to attack a structure fire and accept that kind of flow for all kinds of fires it encounters.
“In that case a fixed-gallonage nozzle is what they need,” he noted. “But another city might want four ranges of flows – 100, 125, 150 and 200 gpm – so either an automatic or variable flow nozzle would be what they need.”
Don Sjolin, Elkhart’s vice president of marketing and strategic development, said comparing nozzles depends on understanding the application needed and the operational procedures of the department, before one is able to see the plusses and minuses of each type of nozzle.
“There’s no universal answer to which nozzle you should be using,” Sjolin said. “There are distinct areas where certain nozzles fit the profile better than others. Once you determine those areas, then you can determine if the manufacturer you prefer has the nozzle you need.”
Sjolin believes that an automatic nozzle offers the largest number of benefits to firefighters, but that much can be accomplished with a variable-flow nozzle used properly.
“You have to define your goals and objectives before you can pick the right tool,” Sjolin said. “The department’s [standard operating procedures] have to be rather narrow in some ways to be sure firefighters have the proper equipment to accomplish the job, and that the nozzles are understood and trained on in a documented way.”
Dave Durstine, vice president of marketing for Akron Brass Co., said he’s also seen a transition in the North American market to fixed-gallonage and solid-stream nozzles.
“Part of it is the KISS principle, keep it simple, stupid,” Durstine said. “Many volunteer departments that don’t train as much or don’t have as much manpower available are looking for simpler solutions, especially because they don’t have the traditional heavy water flows.”
Durstine pointed out that Akron nozzles with a fixed orifice run from 13 gpm to 350 gpm for handlines and from 500 gpm to 5,000 gpm for master-stream appliances. He said Akron’s SaberJet, a combination smoothbore and fog nozzle in a single unit, is available in single and dual shut-off versions.
“The single shut-off is done through the bail (handle) of the nozzle, while the dual model has a twist shut-off on the bumper (rubber ring at the nozzle’s end) and the bail controls the solid stream,” he said. “With the dual model, you can have two types of stream flowing at the same time. So it’s a multipurpose nozzle.”
Durstine noted that departments must decide where they want control of a nozzle before choosing a type.
“You might want control at the end of the hose where the firefighter increases and decreases the flow with an adjustable nozzle like our TurboJet,” he said. “Or you might want it at the pump panel with the pump operator controlling the pressure to either give more flow or to back off because the pressure is knocking the firefighter down on the end of the line.”
Generally, in North America, nozzle pressures are set at 50, 75 or 100 psi, Durstine pointed out.
“The benefits of going with a lower pressure nozzle is that it reduces the reaction force on the firefighter, which means he uses less energy and is less fatigued,” he said. “Then the firefighter can work longer and be more effective on the fireground over a given length of time.”
Rod Carringer, vice president of sales and marketing for Task Force Tips said the combination nozzle with a gallonage selection ring (variable gallonage nozzle) is the most widely made and distributed nozzle Task Force Tips makes.
“A selectable gallonage nozzle gives a crew some options,” he said. “If a firefighter goes into a room with no involvement, he might have the selection set at 60 or 90 gallons, but down the hall if he opens up a room that’s fully involved, he can click the selection ring up to 150, 175 or 200 gpm because he has the ability to vary the orifice size. It’s probably the most commonly used nozzle on the planet.”
However, Carringer pointed out that a firefighter might not get the flow he asks for with a variable gallonage nozzle because the pump operator has to kick up the pressure to deliver the increased flow.
“You need a corresponding change in pressure,” he said. “So there has to be a high level of communication between the firefighter inside and the pump operator outside.”
With an automatic nozzle, the communication issue isn’t as big a concern, Carringer said, because the pressure remains constant throughout a range of flows.
“The National Fire Protection Association calls the automatic nozzle a constant pressure variable gallonage nozzle,” he said. “It uses a spring and an hydraulic balance as part of its design to maintain a constant pressure. The core design of the automatic portion of the nozzle operates very similar to that of a pressure relief valve on a pump.”
Carringer said he has not detected any trends among fire departments toward any particular category of nozzle.
“What we have seen is a move toward lower-pressure nozzles in an effort to reduce nozzle reaction to the crews,” he said. “Where 100 psi was the standard, about a third of our business now is in the lower-pressure nozzles that operate at 50 psi or 75 psi.”
Advantages of lower-pressure nozzles, Carringer pointed out, include lower engine pressures as well as less nozzle reaction on fire crews at the end of the hose line.
While nozzle pressures may be getting reduced, fire flows have also come down as well, which concerns Carringer.
“Fire doesn’t care what type of nozzle you use, only the gallons per second delivered into that fire space,” he said. “You have to put a certain number of gallons per second into a fire space to deal with the BTUs being generated by the fire, and that means you must maintain adequate fire flows for your crews. So you need to choose a nozzle, even if it’s in the range of 50 psi to 75 psi, that can easily generate 150 gpm to 200 gpm on the handline to give you an adequate fire flow to put the fire out.”
Nozzle manufacturers organize their products into general categories. These are the ones used by Elkhart Brass.
Solid stream (also called smoothbore and straight tip)
A nozzle used on a handline or master stream appliance to shape the flow of water in a solid stream. Typically, such nozzles range from 1/4-inch to 3 inches in diameter. The discharge size tip and pressure determine the rated flow of the nozzle.
Benefits: Provides a high volume of water with minimal nozzle reaction; simplicity; good reach and penetration; works well in low-pressure conditions.
A nozzle that provides constant gallonage with an adjustable pattern of spray from straight stream to wide fog.
Benefits: Easy to use; operates in a wide range of nozzle pressures from 50 to 100 psi.
A combination nozzle with multiple gallonage selections that maintains a constant flow at any pattern setting. The rate of delivery is based on nozzle pressure.
Benefits: Able to select and change desired gallonage settings without shutting down the line; has water conservation capabilities.
A pressure-regulating nozzle that maintains constant pressure over a wide range of flows and gives a constant gallonage discharge.
Benefits: Has a wide flow range; maintains an effective nozzle pressure and effective streams; automatically adjusts for changing flows; works well with foam eductors.
NFPA Sets Nozzle Standard
The National Fire Protection Association (NFPA) 1964 Standard on Spray Nozzles applies to nozzles fixed on monitors, as well as those that are handheld.
“NFPA publishes a product standard for which manufacturers design and construct the product to supply to the fire service,” said Larry Stewart, fire service specialist and staff liaison to the NFPA Technical Committee on Fire Hose. “The documentation doesn’t require a third party to certify the product. Rather the manufacturer self-certifies or proclaims they comply with the standard.”
Stewart said NFPA 1964 requires a manufacturer to adhere to requirements for operational design, rough handling, environmental considerations, and road spray. In addition, it requires that nozzles be corrosion resistant, have flushing capabilities to clear themselves, and be able to operate in a wide temperature range.
The standard was first established in 2003, and Stewart said additions were made in 2007. The standard will be reviewed again in 2012 to determine whether it should be modified further.
“Anyone in the general public can submit a proposal to the committee, and it has to consider the proposal,” Stewart said.
The NFPA standard provides general guidelines on how nozzles must perform. For example, he said, a spray nozzle must have a discharge pattern, flow a minimum of 60 gallons per minute, have capabilities of going from straight stream to a wide fog pattern, and have minimum angles at which the fog pattern should flow.
“The NFPA standard requires that nozzles be marked as to the flow so there’s some sort of truth in the advertising,” Stewart said. “The flow needs to be tested.”