By Bill Adams
I don’t advocate using or not using two-inch hose for handlines.
I’ve never handled two-inch on a fireground or during a training scenario and rely on others’ expertise who are more versed in the subject as well as published pieces by people such as “water movement guru” Paul Schapiro (http://bit.ly/2F537TR). I asked Bill Graves, regional sales manager for All American Hose, to weigh in with commentary from a hose manufacturer’s perspective.
1 This Hamlin, New York, engine has two 200-foot 1¾-inch crosslays (red and yellow) and a 200-foot two-inch crosslay (blue). This rig also has two 150-foot 1¾-inch preconnects on top of the driver’s side compartment connected to a gated wye on the pump panel. (Photos 1 and 2 by Allan Smith.)
Except for a few dyed-in-the-wool traditionalists, the fire service has accepted the fact that 1¾-inch hose has replaced 1½-inch as the standard handline for initial attack. Today, using two-inch hose for initial attack is slowly gaining popularity. According to Graves, the attack hose market for 1½-inch hose accounts for 10 percent of sales, 1¾-inch has 75 percent of the sales, and two-inch has the remaining 15 percent. Generic reasons given for changing over to two-inch are lower weight, more maneuverability, less friction loss, and increased flow. If explicit firematic goals and objectives for purchasing two-inch are not clearly defined, the generalized reasons for purchasing can become false narratives.
2 A newer engine from Hamlin has speedays with two 200-foot 1¾-inch preconnects (red and yellow) and a 200-foot two-inch preconnect (blue). All of Hamlin’s rigs have rear preconnects including 300-foot two-inch lines and preconnected portable ground monitors.
It is admirable when innovations and technology make firefighters’ lives easy and safer. Occasionally new concepts, designs, or changes in the fire service create skepticism and occasional ridicule. In the 1950s, firefighters ridiculed putting doors on apparatus cabs, and then they complained about going to fully enclosed four-door cabs. For years, some questioned whose idea it was to mandate using self-contained breathing apparatus. And, then it was foolish to use large-diameter hose. Adopting two-inch hose for handlines can invite similar comments from the uninformed, the uneducated, and unfortunately the ignorant.
Preplanning
This article discusses two-inch hose with 1½-inch couplings. The use of two-inch allows significant changes and increased versatility in fireground tactics and strategies. A contemplated changeover to two-inch should be planned as carefully as the fire department’s preplan for the “big one” on Main Street. Purchasing it because a neighboring department did is not sound reasoning. Establishing goals and objectives will help justify purchases to taxpayers:
â– Will the two-inch replace existing 1¾-inch attack lines?
â– Will it replace the larger 2½-inch handlines?
â– Is it intended to replace both?
â– Is it intended to be another tool in the toolbox complementing existing handlines?
â– How much water are two-inch handlines expected to flow?
â– Importantly, can available staffing handle two-inch handlines?
Purchasers should objectively and equally evaluate the pros and cons of adversarial points of view. If you want more flow from an attack line, are you willing to pump at higher than normal pump pressures? Want lower friction losses? The two-inch has a lower friction loss than 1¾-inch but not lower than 2½-inch. Want less weight? The two-inch weighs less than 2½-inch but not less than 1¾-inch. I do not recommend how to use two-inch, what type of nozzle to use, what flow to seek, or what pressure to pump. Firematic decisions are local and should be investigated in-house. Define what you’re trying to accomplish. Acknowledge that you might have to compromise to get there. Are you getting the best value for the monies expended if the two-inch hose is not used to its fullest potential?
3 This quint from Fishers, New York, carries two 1¾-inch crosslays and a two-inch crosslay. Oversizing crosslay widths will allow for flexibility in future hose loads (sizes and manufacturers). (Photos 3 and 4 by author.)
Friction Loss and Fire Hose
Friction loss (FL) and flows from published charts are theoretical. They do not take into consideration the type of hose construction, the materials used, and possible deterioration of the inner liner of the actual hose a fire department uses. Most FL tables are based on 100-foot sections of hose and not the 50-footers commonly used. And, FL in couplings, fittings, and appliances is not considered. The actual interior diameter of hose can differ in two ways. Some materials used in hose construction stretch when charged. Some don’t always return to their original size. One hose manufacturer’s catalog shows seven methods of construction with multiple types of materials used for two-inch hose. Hose manufacturers may purposely construct hose with slightly larger internal diameters. It gives them bragging rights for larger flows and lower FLs. Consequently, what is seen in a chart may not be what is experienced in the field.
4 This older engine from Fishers has three two-inch speedlays and a 2½-inch crosslay. Fishers’s standard hose loads in the future will be 1¾-inch attack lines and two-inch backup lines.
The following FL measurements [in pounds per square inch (psi)] for various flows in gallons per minute (gpm) for 50-foot sections come from http://frictionlosscalculator.com.
It is obvious that two-inch’s FL is about half as much as 1¾-inch. It has four times more FL than 2½-inch. Don’t panic at the “four times as much” FL. Add the nozzle pressure for the nozzle of choice, and chances are that pump discharge pressures will be within the acceptable operating range of both the fire hose and the fire pump. Will it be within the acceptable operating range of the fire department? That’s a local decision. Flow testing measured by calibrated testing devices is more accurate than the tables and flow charts—if being that accurate matters.
Nozzles
It appears many converts to two-inch are replacing 1¾-inch handlines and at the same time are converting to straight tips (smooth bores)—probably to achieve a lower FL, a low discharge pressure, a larger flow, or all three. Graves observes that many end users, “Are looking at more water with less pressures in handling. Constant-flow nozzles at 75 psi or smooth bore nozzles at 50 psi seem to be the most popular nozzles used with two-inch.”
I will not opine on straight tips vs. combination fog nozzles or high-pressure vs. low-pressure nozzles or any combination thereof. Another argument left for experts is recommending a tip size for smooth bores. Let the nozzle manufacturers discuss those volatile subjects.
THE DEUCE-AND-A-HALF Handline
Some two-inch advocates promote two-inch as an acceptable replacement for a 2½-inch handline flowing volumes up to 250 gpm. In the real world, an understaffed engine company may have a tough time advancing a charged 2½-inch line—more so when flowing water and impossibly so when advancing up a flight of stairs. Staffing-rich departments can assign multiple companies to help with 2½-inch stretches. Those not so fortunate seldom move a big line after it’s charged.
The difference in weight between 50-foot lengths of two-inch and 2½-inch is about eight pounds. The weight of the water in 50 feet of two-inch is 68 pounds. The weight of the water in 50 feet of 2½-inch is 106 pounds. It may be feasible for a two-inch handline flowing 250 gpm to be easily advanced—at least easier than the 2½-inch. I acknowledge that some departments do flow more than 250 gpm from their big lines, and it appears two-inch may fall short for that requirement.
Many hose humpers say, “You can’t beat the reach, penetration, and impact of the deuce-and-a-half with a big smooth bore.” Only field testing both side-by-side will tell. Maneuverability and ease of handing should be determined with field testing by the troops who’ll be using the hose and not by some ready-for-retirement white coat sitting in an office. Don’t do it in the parking lot behind the fire station. Use a training facility and actually replicate advancing a charged line into a large mercantile or to the second floor of a factory building. Then try it when flowing water. Good luck.
While 2½-inch couplings are available on two-inch hose, not too much is written about it. It appears they are beneficial when flowing in excess of 300 gpm. See Shapiro’s article about using two-inch for a large volume handline at http://bit.ly/2sVo66X.
Questions for a Hose OEM
Graves answered the following questions regarding two-inch hose use.
Is two-inch becoming popular for initial attack? “Yes, departments are looking at two-inch for high rise operations. They can get the water flows of 2½-inch landlines with less weight (dry) than a 2½-inch hose. With the success of high-rise hose, departments are looking to use two-inch hoselines for larger flows but less weight than 2½-inch hose.”
When did two-inch start gaining popularity? “In the 1990s when staffing was an issue and the advancement of nozzles to replace flows of 2½-inch hoselines for quick knockdown delivering more water for attack without the weight of a 2½-inch handline.”
Are purchasers using two-inch to replace 2½-inch handlines or 1¾-inch handlines? “Departments are still mostly buying 2½-inch and 1¾-inch landlines. They’re adding two-inch hose for a larger specialty line. Some departments are switching over to all two-inch to replace the 1¾-inch hose.”
At trade shows, what are some of the topics purchasers bring up concerning two-inch hose? “Kinking with low-pressure nozzles, the weight of hose, the fire resistance rating of hose for protection of [the firefighter on the nozzle], where the hose is made (USA or overseas), the approval ratings of hose, its friction loss, availability of color-coding outer jackets, and a list of users.”
Do you find potential purchasers resist increasing pump discharge pressures to maximize flow capabilities of two-inch? “In general, departments are looking for more water with lower pressures in handling the 50- to 75-psi common nozzle pressures today.”
How common is using 2½-inch couplings on two-inch hose? “Departments that are using 2½-inch handlines are using two-inch hose with 2½-inch couplings as the leader line or nozzle line for better movement and handling down a tight hallway in a high-rise type building. They can attach their 2½-inch smooth bore nozzle with a one-inch or 11â„8-inch tip and still get the same flows as a 2½-inch line but with the maneuverability to advance the hoseline down a tight hallway or apartment.”
Space and Specs
Perceived and actual advantages of using two-inch hose can be negated by not designing a new rig to effectively store, deploy, and more importantly supply it. When retrofitting existing rigs to accommodate two-inch, similar factors should be considered to maximize the effectiveness of the switch. Apparatus manufacturers commonly allow seven inches (width) for a double-stacked 1¾-inch crosslay and nine inches for a 2½-inch double-stacked lay. Use caution. Published widths for two-inch hose can differ depending on the material, type of construction, and the manufacturer. One manufacturer publishes the following widths for the various styles of hose it markets: 3.30, 3.40, 3.50, 3.60, 3.68, and 3.70 inches. Those widths are for new, unused hose. Don’t forget the stretch factor previously mentioned. Some hose will stretch and not return to its original width.
When specifying hosebeds on new rigs, ensure the widths will accommodate the hose you intend to use. What a department “thinks” the width of a two-inch hosebed should be may not be the same width the manufacturers use. Write specifications carefully and explicitly. Joe Messmer, president and owner of Summit Fire Apparatus, makes a valid point: “When laying out a crosslay for a single stack of any size fire hose, make sure the bed’s wide enough for your hand to reach the connection. Swivel connections for crosslays should be specified close to a leading edge of the bed.”
When discussing flows, pump discharge pressures, and two-inch hose, seldom addressed is the plumbing on a new rig. Ensure discharges remotely located from the fire pump are sufficiently plumbed. Merely specifying a “rear discharge with two-inch valve and piping terminating with a 1½-inch NST male fitting” does not necessarily mean it will adequately and efficiently supply a two-inch preconnect that’s expected to flow a desired gallonage at a desired pump discharge pressure. Ditto for ones on the front bumper. Piping discharges to the front bumper or to the rear of the bus may necessitate multiple fittings, twists, and turns to get there. It may be advisable to use 2½-inch plumbing for all discharges for handlines.
Work closely with apparatus design engineers. Write purchasing specs carefully, and do not hesitate to require a certified flow test for individual discharges. Another point of consideration when establishing attack line hose sizes, nozzles, and plumbing is that some fire departments use a single predetermined pump discharge pressure for all discharges during an initial attack. That initial preset discharge pressure may not be adjusted until after the fact—if at all.
5 This quint from North Greece, New York, carries one 1¾-inch and one two-inch 200-foot preconnected line. A 300-foot two-inch attack line is also carried. They expect to flow 190 gpm from the 1¾-inch and 250 gpm for the two-inch—all with smooth bores. (Photos 5 and 6 by Greg Knapp.)
End User Experiences with Two-Inch
Frank Riccobono, regional sales representative for Firehouse Apparatus Inc., a 4 Guys and HME Fire Apparatus dealer in Western New York, says he has not done any formal testing but says, “I have personally connected 100 feet of two-inch hose with 1½-inch couplings and a portable monitor with a straight tip to a pump-panel-mounted 1½-inch trash line with two-inch valve and piping, and we did almost 500 gpm. That is my only experience with flow testing the two-inch valve/piping.”
Hamlin, New York: Chief (Ret.) Allan Smith of the Hamlin (NY) Fire District and apparatus sales manager for Colden Enterprises, a Spartan ER dealer in Western New York, comments, “We sold a pumper to a local department with dual two-inch crosslays with 1½-inch chicksan swivels. They wanted to make one into a 2½-inch preconnect, so we put a 1½-inch female by 2½-inch male increaser on the swivel and flowed more than 300 gpm through 200 feet of 2½-inch hose. My department uses a crosslay with two-inch hose for a 300-foot-long line with an automatic nozzle. According to the integral flowmeter built into the rig’s foam system control panel, we can move around 250 gpm at 170-psi pump pressure.”
6 This quint from North Greece, New York, carries one 1¾-inch and one two-inch 200-foot preconnected line. A 300-foot two-inch attack line is also carried. They expect to flow 190 gpm from the 1¾-inch and 250 gpm for the two-inch—all with smooth bores. (Photos 5 and 6 by Greg Knapp.)
North Greece, New York: Greg Knapp, a career captain in the North Greece Fire District outside Rochester, New York, explains how his department uses two-inch hose. “We are running two-inch now and plan on continuing with two new engines on order. The numbers provided are actual flow-tested numbers off of our apparatus with our hose. They are a good baseline but may not apply to someone else’s plumbing design or actual hose. Our goal for 1¾-inch preconnected handlines for structural firefighting is 190 gpm. For two-inch preconnected handlines for structural firefighting, the goal is 250 gpm. We run:
â– 200-foot 1¾-inch line with a one-inch smooth bore tip pumped at 100 psi that flows 190 gpm.
â– 200-foot two-inch line with a 11â„8-inch smooth bore tip pumped at 125 psi that flows 250 gpm.
â– 300-foot two-inch with a 11â„8-inch smooth bore tip pumped at 155 psi that flows 250 gpm.
“I’m pretty confident that with different hose, nozzle selection, or tip size and a different plumbing configuration, you would see some different numbers when flow testing. With that said, I think you need to identify what flow you are trying to achieve, then test your individual apparatus with your brand of hose and see what pressure you need to achieve those numbers.”
Fishers, New York: Chief Andy Stromfeld of the Fishers Fire District, also located outside of Rochester, New York, says Fishers has run two-inch attack lines and 2½ inch backup lines for more than a decade. He said they’ve started transitioning back to 1¾-inch attack lines with two-inch backup lines because of limited staffing. The department’s in-house testing and evaluation have shown it is faster for a limited crew to put a 1¾-inch line into service. Stromfeld says, “Our short-staffed crew using 1¾-inch allows for better maneuverability than the two-inch. With the new manufacturer of two-inch hose we use, there is only a six-gpm difference between the two. But, there is a 60-gpm difference between our 2½-inch and two-inch backup lines. It’s a compromise. We may lose some flow with the two-inch, but we can still get good water on the fire faster with a small crew.”
7 Designing a new rig’s hosebeds with “tight width” hose loads may impede future changing to a different size or even manufacturer of hose. Don’t inadvertently restrict hose removal with folding steps, grab handles, or telescoping light poles and their deflectors. (Photo by author.)
He continues, “Our newest rig, a quint, runs 1¾-inch attack lines with a two-inch backup line. We do run one engine with the two-inch attack lines and 2½-inch backup line; however, all apparatus will eventually run with 200-foot and 300-foot 1¾-inch preconnected attack lines with 7â„8-inch smooth bore nozzles and a single 300-foot two-inch backup line with a 1¼-inch smooth bore. Our goal is to flow 210 gpm through the 1¾-inch preconnects and 315 gpm from the two-inch. Our rigs have pressure governors with preset initial discharge pressures of 120 psi. If you’re looking at two-inch, there is a significant difference in size, weight, and handling over 1¾-inch lines, but if staffing is not a concern, it is worth considering.” (Author’s note: The average weight for a 50-foot section of two-inch hose is about a pound or two more than 1¾-inch, and it holds 16 pounds more water than the 1¾-inch.)
Fire hose, regardless of its size, is a tool that works if used as intended and not abused.
BILL ADAMS is a member of the Fire Apparatus & Emergency Equipment editorial advisory board, a former fire apparatus salesman, and a past chief of the East Rochester (NY) Fire Department. He has 50 years of experience in the volunteer fire service.
