Apparatus Purchasing: Front Bumper Preconnects

Bill Adams

Numerous apparatus manufacturers now offer custom cabs and chassis with preconnected hoselines located on front bumper extensions. I take no side in using front bumpers to store preconnects and show no preference if they are used for structural attack, vehicle fires, or trash lines for nuisance fires. Those are local decisions. The apparatus photographed herein were built to each department’s specifications for the particular requirements of their individual response areas.

This article looks at their layouts from a broad perspective for the entire marketplace and is not intended to disparage any design, manufacturer, or end user. The intent is to help the next purchaser specify and lay out a new rig. First time users who spec a bumper preconnect without doing research may be doing a disservice to their fire department and an injustice to the taxpayers who foot the bill. Considering the investment to extend a bumper; fabricate storage space; and provide the accoutrements, controls, and plumbing for it, a bumper preconnect probably costs more “dollars per gallon delivered” than same sized discharges located elsewhere on the apparatus. Todd McBride, apparatus specialist for Rosenbauer-America, says it’s approximately $1,800 to extend a front bumper with hose wells and about $1,650 to add a two-inch discharge-a $3,450 investment to deliver about 200 gallons per minute (gpm).

removable tray on a pumper

(1) This removable tray on a pumper for Alexandria, Virginia, is set
close to the cab fascia. Lift-to-turn D-ring latches on each end enable
quick removal of the tray when tilting the cab. (Photo courtesy by
CustomFIRE.)

 

Purchasers address bumper preconnects three ways. One is based on past experience. The department has one, likes the way it works, and wants to replicate it. That has merit. Another is to purposely design them to be job-specific. That shows planning, initiative, and foresight. The third way may lack judgment and astuteness. As an example, a neighboring department might have one, and the apparatus purchasing committee (APC) thinks it’s a good idea. It specs one without giving much thought to it. If there is no rhyme or reason to the decision, it’s like buying a pair of shoes without first trying them on. You hope they fit. Good luck.

Vendors are obligated to ensure the components they recommend to an APC will actually meet the APC’s expectations. Rather than placating an APC, vendors should be asking pertinent questions to enable the APC to make informed decisions. What flow is expected? Is it foam-capable? Will it be used for initial attack? How much hose is to be carried? How do you plan to deploy it? Purchasers must be made aware of any impact on the overall apparatus length, wall-to-wall and curb-to-curb turning radii, the angle of approach, and overall weight distribution. By the way, how much will it cost, and is it cost-effective? McBride explains that a 2½-inch bumper discharge costs about 15 percent more than a two-inch discharge with a net gain of 50 percent more water. It seems incomprehensible that an APC would consider a front bumper preconnect without addressing pertinent firematic and financial issues.

Crosslays laid flat on this cab and chassis

(2) Crosslays laid flat on this cab and chassis look neat but could be
awkward to deploy. It is essential to remove all trapped air and water
before repacking to ensure covers close completely. Hose
connections are recessed below the apron. (Photo by author.)

 

NFPA 1901

National Fire Protection Association (NFPA) 1901, Standard for Automotive Fire Apparatus, requires apparatus equipped with pumps be provided with two storage areas to accommodate 1½-inch or larger preconnected hose, each with a minimum of 3½ cubic feet. Be careful if you expect front bumper preconnects to meet this requirement. Chances are if they were not specified to be NFPA-compliant, they will not be. There may not be a problem with crosslay configurations, but there could be when using the manufacturer’s standard bumper compartments that serve double duty as hose wells. To meet NFPA 1901’s cubic footage requirements, more than one hose well for each preconnect or custom built job-specific enclosures may be required. On the other hand, does it really matter if they are NFPA-compliant? I know of no NFPA “hose storage enforcement division” that fire departments should fear. However, it is the vendor’s responsibility to make purchasers aware of regulatory compliance issues as well as cost, space limitations, and operational characteristics.

Bumper Crosslays

Single or dual crosslays can be mounted on top of the bumper apron, partially recessed into it, or fully recessed beneath it. The latter requires extensive modification to the structural supports beneath the extension. Purchasers should be aware that some projections above the bumper apron close to the cab may impede the cab tilting. Photo 1 shows an easily removable lift-off tray for dual bumper preconnects that allows them to be mounted close to the cab’s fascia.

One good sized eastern career department experimented for several years with dual bumper crosslay configurations on a half dozen rigs. Firefighters complained they were inconvenient to impossible to shoulder load and advance. Besides their being hard to deploy, firefighters complained they were difficult to repack (not enough room). That department returned to pumphouse-mounted crosslays and rear preconnects in the main hosebed. It may be prudent to experiment in-house or at the least network with other users before purchasing.

This pumper has a fully recessed center-mounted hose well

(3) This pumper has a fully recessed center-mounted hose
well. Preconnected hose is packed on its edge and fed by a
single two-inch discharge. (Photo by author.)

 

When only used as a “trash line” for nuisance runs, bumper hoseline advancement speed and efficiency may not be relevant. I have observed that many are piped for foam application. Consequently, the expedient removal and rapid advancement of a preconnect for flammable liquid fires or a vehicle fire may enter into the decision making process when evaluating storage methods.

Hose Wells

Standard size bumper compartments (aka hose wells) vary among manufacturers. About 30- to 34-inch-wide compartments are available in the center between the frame rails, with about 13- to 18-inch-wide compartments outboard of the frame rails. Width variations reflect air horn locations. Take note: When you specify angled bumper corners, the wall-to-wall turning radius is decreased, which is good. However, the capacity of outboard hose wells is also reduced, which is not so good.

Another consideration is the depth of the hose wells. Most standard bumper compartments are about 12 inches deep. Customized depths are available but probably cost more. Ask. Extensions capable of accommodating hose wells can extend from about 1½ feet to more than 2½ feet from the cab fascia. A 21- to 24-inch extension is likely required to realize 3½ cubic feet in the center hose well. Even with a 24-inch extension, outboard compartment capacity may be less than two cubic feet.

This pumper features hose wells mounted outboard of the frame rails with hose packed on its edge

(4) This pumper features hose wells mounted outboard of the
frame rails with hose packed on its edge. Both are supplied by
a water thief attached to a single center-mounted discharge
elbow. Ensure valve and piping is adequate to supply
intended flows. (Photo by author.)

 

Caution: Deep hose wells may infringe on the angle of approach and become a magnet for curbs. NFPA 1901 sentence 12.3.2.3 specifies a minimum eight-degree angle of approach. McBride notes, “The NFPA doesn’t know your response area so I wouldn’t put too much emphasis on trucks that are just compliant with NFPA minimums concerning angles of approach and departure. The truck has to be designed to work in your area. These are critical factors that the department will have to face for as long as it owns the truck. So, it’s important to work with a dealership that understands the challenges and can manufacture a truck that is built for your response area.” That’s sound advice. When evaluating proposals, how does an APC determine how much better a 12-degree angle of approach is compared with the eight-degree angle required by the NFPA? Heed McBride’s advice-work closely with the vendor.

Don’t forget ground clearance. It can be as critical as the angle of approach. NFPA 1901 sentence 12.3.2.2 states, “Axle housings and any components other than wheels and tires shall clear the road surface by at least eight inches (203 mm).” How high are your curbs?

Packing

Bumper crosslays are usually loaded flat (photo 2) or packed on edge (photo 3). While some users pack hose wells similarly (photo 4), others use donut rolls (not just a coiled length, but one folded in half over itself and rolled from the middle with both couplings being exposed on the outside). Others use vertical folds with pull loops to lift a portion or the entire load out of the well (photos 5 and 6). Yet others use a combination of both (photo 7). Donut rolls can be coupled together and set in a hose well. Pick one up, drop it on the ground, and carry the one with the nozzle to wherever you’re going. It works sweet. News flash: Fire hose does not have to come in 50-foot lengths. Consider having hose lengths sized to fit a hose storage area. It may make life easier on the fireground.

The rolled tops on the preconnect hose wells on this pumper facilitate hose removal without snagging couplings

(5) The rolled tops on the preconnect hose wells on this
pumper facilitate hose removal without snagging couplings. It’s a
neat idea. Hose is loaded with vertical folds and pull loops to aid
in removal. A separate two-inch discharge is provided for each.
(Photo by author.)

 

Entering “front bumper preconnects” into a search engine results in a multitude of hits from end users, trade journals, and fire service blogs and forums showing various ways to load and deploy bumper preconnects as well as real-life end-user experiences. It’s worth reading.

At a recent trade show, there seemed to be a preference among departments for using hold-down straps to secure bumper preconnects. When using straps in lieu of a tight fitting cover, it’s easier to “fit” the hose and nozzle. If dirt, road debris, and inclement weather are concerns, a cover may be in order. If the intent is to store a nozzle with the hose and still close the cover, ensure the purchasing specifications say so. They usually don’t. Bear in mind that when new hose is packed into bumper trays and hose wells, it looks good and fits well. But after it has been well used, gets stretched, becomes dirty, and possibly has air and water trapped inside, it may not pack as well. Plan accordingly-if it’s possible.

The hose load with vertical folds and pull loops features commonly used hold-down straps

(6) This unit has center and driver’s side hose wells fed by a
single 2½-inch discharge with a gated wye. The hose load
with vertical folds and pull loops features commonly used
hold-down straps. (Photo by author.)

 

Flows and Friction Loss

Most purchasers pay little attention to the gallons per minute (gpm) expected from a bumper discharge. It’s seldom addressed in purchasing specs. Some departments have the same size and length preconnects located on the bumper, in a midship crosslay, and in the main hosebed piped to the rear of the apparatus. Operationally, if all are pumped at the same discharge pressure, does each flow the same gpm? It’s doubtful. Bear in mind, the more complex and lengthy discharge plumbing is, the greater the friction loss. Have you ever considered conducting flow tests on your preconnects?

This engine features two preconnects in a divided center hose well

(7) This engine features two preconnects in a divided center
hose well, each fed by a separate two-inch discharge. Both
preconnects lead off with a donut roll with nozzle attached.
(Photo by author.)

 

While piping configurations vary from manufacturer to manufacturer, it’s conceivable a single 2½-inch bumper discharge with a full flow valve can deliver 500 to 600 gpm. It’s also possible there could be upward of 50 psi friction loss in the discharge piping from the pump header, out of the pumphouse, down under the cab, over the axle, and up through the bumper apron to wherever you locate the 90-degree swiveling elbow discharge. Consider the friction loss in each length of hose and any appliances used. What nozzle pressure do you want at the end of your line? Work closely with the manufacturer. Don’t reinvent the wheel. Someone may have done flow tests before. Ask. It’s also important to ensure wyes (photo 6) and water thiefs (photo 4) mounted on discharge elbows are either removed or pointed away from the cab fascia prior to tilting the cab. The same applies to portable monitors (photo 8). Not doing so can be embarrassing as well as costly.

preconnected portable monitor on the front bumper

(8) This pumper from Mumford, New York, has a preconnected
portable monitor on the front bumper. (Photo by Allan Smith.)

 

Job-Specific Front Bumper

DeForest Area Fire and EMS, a combination department covering 89 squares miles in five municipalities north of Madison, Wisconsin, responds to about 1,200 incidents per year in a predominantly residential and agricultural area. Deputy Chief of Fire Operations Brent Foss notes the idea of “nosing a truck into the scene and going to work off the front” in his department started with the bumper mounting of auto extrication equipment on a squad (heavy rescue) the department purchased in 2003. It worked. He says, “We just adapted the idea for firefighting too,” elaborating that the concept of an “attack bumper” is logical when pulling down a driveway, into a barnyard, or into a parking lot (photo 9).

bumper-mounted preconnect

(9) Engine 1’s crew from Deforest (WI) Fire and EMS prepares
to deploy a bumper-mounted preconnect on a narrow
driveway typically found in the district. (Photo courtesy of
CustomFIRE.)

 

He continues, “We have two bumper lines, each plumbed with three-inch flex hose to a 2½-inch discharge. Each discharge is reduced with a gated wye, allowing us to potentially connect up to four handlines off the ‘attack bumper’ (photo 10). The two preconnected hose loads are each 200 feet of 1¾-inch hose with a Task Force Tips 15⁄16-inch VIT nozzle and a detachable automatic tip. Since these lines are compressed air foam system (CAFS) lines, we run the smooth bore VIT but can attach the fog tip if we switch over to regular class A or straight water.” Foss notes the department APC’s close interaction with the manufacturer resulted in a design that worked as planned. He states, “There were no surprises” when the rig was delivered.

attack bumper

(10) This job-specific “attack bumper” has dual discharges fed
by three-inch piping, each with a gated wye. Stainless steel
hose wells accommodate 200 feet of preconnected 1¾-inch
hose each. The apron is also stainless steel. (Photo courtesy
of CustomFIRE.)

 

Specifications

It is highly recommended to have the firefighters who are going to use them physically deploy and repack similar bumper preconnects before specifying one. If they don’t like it, they may be reluctant to use it. Then be very specific in describing the same. Be careful not to specify a hose well dimension or capacity in one part of your purchasing specification and, in another area, inadvertently compromise it when specifying the location of air horns, siren speakers, plumbing, recessed bumper lighting, and mechanical sirens. You can’t have it both ways.

job-specific bumper extension has two center-mounted hose wells with rounded bottoms

(11) Another job-specific bumper extension has two center-mounted
hose wells with rounded bottoms, each designed to carry four 50-foot
donut rolls of 1¾-inch hose. (Photo courtesy of CustomFIRE.)

 

Foss advises, “Pay the extra money to plumb your discharges with a minimum of three-inch piping with 2½-inch threads. Reducers are cheap. If you ever need to reconfigure your apparatus or simply support a larger line at a fire scene, you will have that option.”

fully enclosed booster reel on the front

(12) This rig has a fully enclosed booster reel on the front
bumper. Note how an angled bumper reduces the size of
compartments outboard of the frame rails. A 2½-inch
discharge with a reducer extends through the front face of the
bumper. (Photo by author.)

 

Foss concludes, “I have mentioned this to everyone I have ever talked to about specing a truck. Every manufacturer makes good trucks and bad trucks. It is your responsibility as a purchaser to know exactly what you’re specing and buying. You should know your spec forward and backward by memory. Read it and reread it constantly so you know what you’re going to get. The manufacturers don’t always think like firefighters-they read the specs. It is your responsibility to convey what you want to them in no uncertain terms.” He hits the nail on the head.

BILL ADAMS is a former fire apparatus salesman, a past chief, and an active member of the East Rochester (NY) Fire Department. He has more than 45 years of experience in the volunteer fire service.

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