Apparatus, Pumpers

Mini Pumpers, Part 1: How Well Do They Really Work?

Issue 9 and Volume 19.

By Bill Adams

 

There appears to be a resurgence of interest in mini pumpers. Apparatus manufacturers promote 1,500-gallon-per-minute (gpm) pumps, four-door cabs, extra compartmentation, foam systems, and tank capacities exceeding 400 gallons.

 

Caution: Read between the lines. Everything a department wants may not fit in one package. More importantly, it may not function as intended. This article only considers mini pumpers compliant with National Fire Protection Association (NFPA) 1901, Standard for Automotive Fire Apparatus, Chapter 6, Initial Attack Apparatus, with a maximum gross vehicle weight rating (GVWR) of less than 20,000 pounds.

NFPA 1901

rig is typical of mini pumpers purchased during the late 1970s and early 1980s
1 This rig is typical of mini pumpers purchased during the late 1970s and early 1980s. Some eclipsed the chassis’ GVWR. Prohibiting personnel from the rear step cut staffing in half. [Photo courtesy of Commissioner Bob Ockenden, Penfield (NY) Fire District.]

Chapter 6’s basic requirements for an initial attack apparatus include a minimum 250-gpm pump, 200-gallon water tank, 22 cubic feet of compartmentation, and 10 cubic feet of storage space for 2½-inch or larger hose. Chapter 5, Pumper Fire Apparatus, requires a 750-gpm pump, 300-gallon water tank, almost twice the compartmentation, and three times as much space for 2½-inch or larger hose. Just because a mini pumper’s pump, tank, and hosebed capacity equal a pumper’s does not necessarily mean it is one. NFPA 1901’s mandatory and recommended ancillary equipment varies between pumpers and initial attack apparatus. Besides physical differences, there are operational considerations purchasers should be aware of.

Mini pumpers became popular in the 1970s and remained so for about two decades; then their popularity suddenly declined. My opinion is that earlier purchasers made the mistake of attempting to replace full-size pumpers with diminutive look-alikes. It didn’t work back then and may not work today. Some fire departments successfully operated mini pumpers. Others found the concept unworkable and abandoned their use. Yet others, finding them not working as intended, revised standard operating procedures (SOPs) to maximize the mini pumpers’ capabilities and minimize their limitations.

Egypt (NY) Fire Department

The Egypt (NY) Fire Department's second-generation, mission-specific mini pumper was not intended to replace a full-size pumper meeting NFPA 1901 Chapter 5 or a grass fire truck
The Egypt (NY) Fire Department's second-generation, mission-specific mini pumper was not intended to replace a full-size pumper meeting NFPA 1901 Chapter 5 or a grass fire truck
2 3 The Egypt (NY) Fire Department’s second-generation, mission-specific mini pumper was not intended to replace a full-size pumper meeting NFPA 1901 Chapter 5 or a grass fire truck. Its total in-service weight is 17,720 pounds. Add 1,300 pounds for a four-door cab and 250 pounds each for four firefighters, and the truck exceeds the 20,000-pound GVWR. (Photos 2-5 by author.)

In the mid 1980s, the Egypt (NY) Fire Department, a volunteer entity outside of Rochester, New York, operated three full-size pumpers, a ladder truck, a rescue truck, and a brush truck out of two stations. Embracing the mini pumper concept, it purchased a two-door unit to specifically run first due on all structure-related alarms, with projected staffing of two in the cab and three on the tailboard. It didn’t work. First, the rig was overloaded. Second, after adopting the 1991 edition of NFPA 1901’s guidelines for only riding in fully enclosed cabs, the five-person crew became two riding in the cab comfortably or three riding cramped. According to past chief Dale Olson, “In good conscience, we could not send it out the door with everything we wanted to carry and the crew we wanted to staff it.”

Egypt restricted the mini’s first-due structural responses to addresses with limited-access driveways. A full-size pumper followed it immediately, if not simultaneously. It essentially ran as the first piece of a two-piece engine company. After years of experience, the department further integrated the mini pumper, with its reduced capabilities, into its SOPs. It proved useful when accessing remote areas requiring a vehicle with greater fire capabilities than a brush truck but not necessarily that of a full-size pumper. Regarding how well the old mini performed, past chief Jack DeLisio says, “Well enough that we bought another one.” Olson adds, “The concept, with modifications based on experience, worked.”

Egypt’s New Mini

Egypt's newest mini carries 1,500 feet of three-inch DJRL in a split bed
4 Egypt’s newest mini carries 1,500 feet of three-inch DJRL in a split bed. A preconnected 2½-inch line is located at the rear.

Purchased in 2005, the new mini pumper features a 750-gpm pump, a 20-gallon Class A foam tank, a 250-gallon booster tank, two 1¾-inch preconnected crosslays, a rear 2½-inch preconnect, and 1,500 feet of three-inch double-jacketed rubber-lined (DJRL) hose in a split bed. Both past chiefs were adamant in stating firefighter safety was priority one. Making maximum use of the available 19,500-pound GVWR was priority two.

They responded to several questions. On why only a 750-gpm pump, Olson says, “It’s not replacing a full-size pumper. Supplying a couple of preconnects (1¾-inch) and a backup 2 1⁄2 is all we expect it to do. Besides, there’s not enough room or carrying capacity (GVWR) for additional handlines.” DeLisio explains that the apparatus doesn’t carry large-diameter hose (LDH) because of its weight and the space required. He adds that a four-door cab is “less maneuverable, [has a] longer wheelbase, and [has] less carrying capacity for equipment and water” than a two-door cab. Why no booster reel? “It weighs too much. Besides, we have a brush truck. We put 200 feet of one-inch forestry hose on it for the few times it’s used for grass fires,” says Olson.

dead lay of one-inch forestry hose is available if the mini has to supplement the department's grass fire truck
5 A dead lay of one-inch forestry hose is available if the mini has to supplement the department’s grass fire truck. The total investment is only several hundred dollars; it takes up less space and only weighs a fraction of a booster reel system.

Egypt added a full complement of EMS equipment and a small portable generator with auxiliary lighting. Both proved useful when deployed first due during heavy snowfalls, especially when the mini pumper was the only rig that could access an incident.

DeLisio says that adding some of the additional ancillary equipment such as the generator, lighting, foam system, extra self-contained breathing apparatus (SCBA), and spare cylinders far outweighed the advantage of a four-door cab. Olson states, “The new mini pumper is an asset to the Egypt Fire Department based on almost 10 years of experience.” He further elaborates that the cost to operate and maintain the mini pumper is much less than a full-size apparatus.

Penfield

Another Monroe County, New York, volunteer department, the Penfield Fire District, purchased a two-door mini pumper in 1980. At that time, the district operated three engines, a ladder truck, a brush truck, and a utility vehicle out of two stations. The mini was first due out of the main station for all alarms except motor vehicle accidents with entrapment because there was inadequate space on the apparatus to carry all the extrication equipment.

With a 250-gallon tank and a 400-gpm pump, it normally responded with two in the cab and three riding the tailboard. Procedure was to respond straight in (dry), pulling off the road. It could lay down long driveways with its 600 feet of three-inch supply line. The first-arriving full-size pumper, carrying a 750-gallon tank and 1,500 feet of LDH, would supply it. In rare instances when the full-size pumper from the substation arrived first, the mini pumper concept did not work. Penfield fire commissioner and past chief Bob Ockenden notes that an immediate drawback was that personnel could not don SCBA en route.

He adds, “After personnel were prohibited from riding the tailboard, it was removed from responding first out because of inadequate staffing. Only two people could safely ride in the cab. When a third station was opened, it was housed there with a full-size pumper. It only responded to EMS calls, as a backup to the brush truck and as needed for off-road incidents.” Ockenden says that based on Penfield’s fireground experiences, the mini lacked adequate fire power-water, supply line, and pump capacity-to meet the district’s requirements. Penfield eventually retired the truck from service and replaced it with another grass fire truck.

Two-Door or Four-Door?

Regardless of the rig’s function, this article does not discuss how many firefighters should or should not staff a mini pumper. There is no discussion of what type of alarms it may respond to or in what order. Those are local matters. Purchasers should be aware of physical differences between two- and four-door cabs. To make a fair comparison, a fictitious firematic back end of a proposed mini pumper requires a chassis with a cab-to-rear-axle measurement of 84 inches. A two-door chassis needs a 165-inch wheelbase. A four door chassis requires a 200-inch wheelbase-almost three feet longer.

A Ford datasheet states the curb-to-curb turning radius of an F-550 with a 165-inch wheelbase is 21.15 feet. The turning radius for an F-550 with a 200-inch wheelbase is 28.90 feet-more than a third more. Double the figure for the distance required to make a curb-to-curb U-turn. Bear in mind that these figures are curb-to-curb. Any front bumper extension will impact real-world wall-to-wall turning radius. Some purchasers consider a mini pumper an overgrown pickup truck. They should bear in mind that some custom chassied full-size pumpers may have shorter wheelbases and shorter turning radii.

Another consideration is weight. To eliminate preferences and hype from apparatus manufacturers promoting a material or method of construction, this article only addresses the bare cab and chassis weight. A two-door F-550 weighs 7,220 pounds. Fifty-eight percent (4,190 pounds) is on the front axle with 3,030 pounds on the rear axle. A four-door F-550 weighs 8,520 pounds with 5,260 pounds on the front axle and 3,260 pounds on the rear axle.

Beware if a vendor says there’s “only” a 1,300-pound weight difference. The final weight calculations should consider an additional 250 pounds for each firefighter in the cab. Plus, add about 50 pounds for each extra SCBA, spare SCBA cylinder, and mounting brackets. Some of that weight will end up on the front axle-perhaps exceeding an axle’s 6,000-pound GVWR. Is there a value in the 1,300-pound variation? What else can be carried? As an example, consider how much weight 150 gallons of water, which weighs 8.34 pounds per gallon, will add. Make use of the qualified design engineers the fire apparatus manufacturers employ. They can accurately inform a purchaser how much of what a mini pumper can carry and, more important, where on the apparatus to carry it.

Recommendations for Purchasers

DeLisio notes that an apparatus purchasing committee should be very mission-specific when considering a mini pumper. Olson comments that there is very limited GVWR and space to accommodate a department’s wish list: “We learned with our first mini that we put too much [weight] on it. We knew better the second time.” They caution that a mini pumper cannot replace a fully equipped full-size pumper. Both say a four-door chassis with a 19,500-pound GVWR would not have met their needs. Ockenden says, “Fire departments should prioritize staffing, hose load, preconnects, tank size, pump capacity, and compartment space when considering a mini pumper. Also, when apparatus respond from multiple stations, consider what happens when the mini pumper does not arrive in the order it was intended to.”

A helpful tool is the Fire Apparatus Manufacturers’ Association (FAMA) Weight and Cube Calculator, which can be downloaded free of charge from its Web site. FAMA states, “It is intended for free use by the fire service in developing safer fire apparatus. Its purpose is to calculate the weight and volume of equipment carried on fire apparatus.” It is an invaluable asset for fire apparatus purchasing committees in the initial design stage for apparatus such as mini pumpers with limited weight capacities. Another resource is NFPA 1901, which lists ancillary equipment that is mandatory for initial attack apparatus to carry and what it recommends should be carried. Choose wisely. Apparatus manufacturers will address mini pumpers in Part 2.

BILL ADAMS is 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.


Egypt (NY) Fire Department’s Mini Pumper Running Order

 

  • First due only for structure-related alarms with limited-access driveways. Last out on all other structure calls. On the initial dispatch, computer-aided dispatch protocol indicates addresses within the district with limited access.
  • In lieu of or before the heavy rescue, it can respond with limited staffing for emergency medical service (EMS) calls.
  • As needed to augment the brush truck and full-size pumpers for grass fires.
  • Last out for motor vehicle accidents to provide traffic control. It is equipped with a rear-mounted traffic directional light.
  • During inclement weather, it is the first responding officer’s judgment call to roll the mini first on any alarm. The Rochester area averages about ten feet of snow per season, which makes its size and four-wheel-drive capability a necessity on roads with appreciable grades; unplowed parking lots; side streets; and long, narrow driveways.
  • Second out as part of the rapid intervention company (RIC). Local mutual-aid protocol requires a minimum of five and allows a maximum of eight personnel responding mutual aid as a RIC. Egypt’s officers prefer sending more than the minimum staffing required. Its pumpers only have seating for six, so the mini pumper can respond as the second piece for a RIC response.
  • As requested for mutual aid.