Since the days of bucket brigades, the fire service has continuously looked for more efficient ways to move water from source to scene to fire.
The advancements are numerous, from water supply to fire ground – including bigger and better pumps, custom tankers and more efficient techniques, to name a few.
But improvements are not just limited to apparatus or training. They also extend to a fire service fixture in use even before the hand-powered pumps and steam engines of the late 19th century: fire hose.
Given the newest technology thermal imagers, compressed air foam systems, advanced breathing apparatus designs and the like available to firefighters, hose appears a rather simple component of firefighting operations. Appearances can be deceptive.
“Fire hose is one of the workhorses in the industry that just has to work all the time,” says Charlie Genther, president of Miami, Fla. based Key Fire Hose Corp., makers of everything from 1 inch forestry hose to 6 inch large diameter hose. “Nothing else works at putting out a fire if your hose doesn’t work.”
The U.S. fire hose market totals between $80 million and $100 million annually, those in the industry say. North American manufacturers supply about 90 percent of the U.S. market, with a wide range of sizes and types.
They range from 1 inch forestry hose to attack hose of diameters from 1.5 inch to 2.5 inches. They also include large diameter supply hose (LDH), typically measuring 4, 5 and 6 inches. Some large city departments still have 3 inch supply hose on apparatus but it represents a very small minority.
Factor in couplings and an array of colors, as well as the various materials and types of hoses, and the product list becomes a long one.
Typically, however, municipal hose falls into the two main categories: attack hose and supply hose, or LDH.
Attack hose for delivering water directly on the fire is either rubber covered or has a fabric jacket lined with rubber or a polymer.
Chief among the advancements in attack hose has been the introduction of synthetics. Polyester or a nylon blend is now used for virtually all woven hose jackets, replacing the cotton fiber in use for just about 100 years the mid 1880s to mid 1980s.
You don’t have to dry out modern synthetic jacketed hose before repacking it. As long as it is free of dirt and soot, wet hose won’t rot, mildew or deteriorate if rolled for storage or placed back on the apparatus.
Most attack hose now comes in a variety of colors and you can be sure any colored fiber hose has a synthetic jacket.
The 50 foot high hose drying towers that were a dominant feature of 19th and early 20th century fire stations are a thing of the past.
Man made fibers brought many significant changes. “Polyester hose is inert to mildew,” says Phil Graham, director of sales for Snap-tite Hose, Inc., in Union City, Pa. Like Key, Snap-tite manufactures hose from 1 inch to 6 inch and larger.
“In the old days,” Graham says. “You have to dry cotton hose jackets thoroughly or it would grow mildew, smell bad and rot.” Synthetic fibers don’t degrade, don’t rot, and overall, modern hose lasts a lot longer.”
“It’s the dirt on the hose that will produce mildew growth, not the actual hose,” says Monique Labbe, marketing assistant with Niedner, a Canadian based fire hose manufacturer.
Niedner, which produces both synthetic woven jacketed, rubber lined fire hose and lightweight polyurethane lined hose, sells 80 to 85 percent of its products into U.S. markets, with the rest sold in Canada.
As long as hoses are periodically cleaned, they can be put away wet, making drying towers a thing of the past, Labbe said. “There may be some people that still prefer to hang hose in towers if they have them, but I’m sure there are less and less departments continuing to do that,” she says.
In the days of cotton or cotton/poly hose, fire companies traditionally kept two hose loads, one on the truck and the other stored in ready racks for reload after a fire, according to Labbe.
Modern hose drying racks and hot air hose drying systems are still sold to dry hose quickly if it has to be washed clean after a particularly dirty operation. However, more than 90 percent of the cotton jacketed hose is history on today’s apparatus.
Old hose with a deteriorated rubber lining is not only subject to leaks and bursting under pressure, but large chunks of dried rubber get stripped off and sent through the fire pump where they can cause damage.
Production techniques vary. The jacket provides hose strength and protection. It’s woven on a circular loom, then reinforced and sealed with a rubber or polymer liner. Cut to standard lengths, the hose couplings are then applied with a two piece pressure fit.
“Everybody has looms,” says Mike Aubuchon, president of Santa Maria, Calif. based North American Fire Hose Corp., the only domestic manufacturer west of the Mississippi River. Like its competitors, North American manufactures industrial and municipal firefighting hose, as well as for the forestry market, which is particularly popular in the West.
“We weave the jackets, which are the reinforcement,” Aubuchon says, producing them from polyester, nylon or a combination of both. Nylon, he says, is more costly, but provides better performance characteristics.
“Nylon gives us improved abrasion resistance and kink resistance, lighter weight and a more compact hose not losing anything in strength,” he says. “Kink resistance is also a bigger issue these days due to the use low pressure nozzles.”
Though there are many variations of fabrics and linings, double jacketed polyester hose tends to be the most common and most economical, those in the industry agree.
Since the early 1990s, ethylene propylene-diene-terpolymer (EPDM) has been the most common lining material, says Snap-tite’s Graham, a 35 year industry veteran, who was with hosemaker Angus Fire when EPDM was introduced.
Before EPDM, styrene butadiene rubber, or SBR, was more commonly used. Graham says EPDM proved easier to extrude, cost less and contained several beneficial properties, including its chemical resistance and a wider temperature range than SBR.
“You try to drive cost out of something without making the product inferior, and you try to get a marketing advantage,” he says. “My job was to make the EPDM a household name in the firehouse.”
After manufacture, couplings get applied. These days, extruded aluminum hard coated and anodized has replaced brass as the material of choice for couplings, largely because it is lighter, says Graham. The transition began during the mid 1960s, but wasn’t easy to convince the tradition bound chiefs of that era, he said.
“Brass was the coupling of choice,” Graham recalled. Aluminum was thought to be “soft and pliable, so we hard coated it. Many didn’t believe it was as durable as the much heavier brass couplings.”
But not only are aluminum couplings lighter, they are more cost effective, especially since copper, a chief component of brass, has increased doubled in price.
Just as attack hose’s makeup and components vary, so do diameters, which range from 1.5 inches to 2.5 inches. Most common, say those in the industry, is 1.75-inch hose, which can move 50 gallons-per-minute more water than 1.5-inch and handles more easily than 2- or 2.5-inch hose.
“There’s always trade-offs,” says North American’s Aubuchon. “As you go up in diameter, from 1.5 inches to 1.75 or 2.5 ? to 3, there is significantly less friction loss and resulting pressure drop.”
However larger diameter hose is heavier and occupies more space. And there are other factors to consider.
“The synthetic fabric jacket is really, really popular as an attack line,” says Genther of Key Fire Hose, noting it can be dragged through buildings more easily turn corners well. “Most departments buy 50-foot hose lengths for their attack hose. The vast majority want the 1.75-inch with the 1.5-inch fitting.
Mercedes Textiles of Canada produces much of the fire hose sold in the United States and uses a different lining than others. “What makes us a bit unique is that we have a patented hose manufacturing process,” says Elizabeth Richardson, vice president of manufacturing.
For its thin-walled hose, Mercedes’ extrudes liquid polyurethane into the woven-fabric jacket as it comes off the loom, rather than applying the lining with an adhesive.
Instead of following the corrugation of the fabric weave, the polyurethane fills the voids, resulting in a smoother surface inside the hose, Richardson says.
“Weight for weight, we’re the same, comparatively speaking,” she adds. “But with the same pump-pressure, you’re going to get more water coming out the nozzle than with hose from competitors, all things being equal, because there’s less friction loss.”
Since the lining is not attached with adhesives, there are no adhesives to degrade, she notes. “Over time, it does not break down, giving Mercedes Textiles its main selling points: less friction loss and no adhesives.”
Attack hose makes up just part of the equation. Water also needs to be moved from source to scene, and when it comes to moving large volumes, and as technology has allowed production of larger diameters, that has increased the use of LDH.
“The New England states started the LDH trend back in the 1960s,” Genther recalls, with imported German hose. That original 4-inch diameter size remains popular there today, he says. Much of the country has adopted 5-inch hose for supply lines so 4- and 5-inch have essentially replaced 3-inch cotton jacketed supply hose that gained some popularity in the mid 1960s in large cities.
And while 6-inch hose moves more water, it’s heavier than 5-inch and requires heavier couplings, as well as a larger volume of available water, Genther says.
In general, LDH consists of two types: rubber-covered hose and double-jacketed, the latter more popular west of the Mississippi River.
North American produces a double-jacketed LDH made of two individual layers of fabric. The result, Aubuchon says, is greater burst strength and greater pressure capacity, but more expensive hose. The largest volume of LDH the company produces is nitrile synthetic rubber-covered and single jacketed.
When it comes to joining LDH-commonly used in 100-foot lengths-the “Storz” couplings-named for European inventor Carl August Guido Storz and first available in Europe before introduction to North America-have become standard. This is a quick-connect, snap-lock design. But on West Coast standard threaded couplings have remained popular.
The Storz couplings came with advantages, says Graham, noting Angus was the first to introduce them in the United States in the 1960s. A primary gain is that the couplings are sexless, eliminating distinctive male and female ends making them suitable for forward or reverse lays.
“The whole idea was it was quick and easy,” he says. “You could lay forward, backward without a need for adapters. You could do whatever you wanted.”
So what to use, given the variables among attack hose and LDH? In short, what goes on the hose bed depends on individual departments’ requirements and standards.
“Each department has its own requirements,” Genther says. Each faces its own circumstances, so apparatus, for example, designed for a Southern city, might not work on Boston’s narrow streets.
Genther says he leaves the decisions on hose up to individual departments.
“Our belief is we know how to make fire hose,” he says. “We don’t know how to put out fires.”