Adams, Apparatus, Chassis Components, Pumpers, Riley

Rear Mounts Preferred

Issue 10 and Volume 22.

Editor’s note: Pumps can be mounted and controlled from almost anywhere on a pumper. This month, Editorial Advisory Board members Bill Adams (left) and Ricky Riley (right) discuss whether they have a preference for the pump location on a pumper and, if so, what the operational reason for that preference is. Do you have a topic for FA Viewpoints? E-mail it to Chris Mc Loone ([email protected]).

This viewpoint is addressed with biased personal opinion from a nontechnical perspective without substantiating data or corroborating documentation. Midship pumps are the most common. Rear pumps, my favorite, are not. Front-mounted pumps are only used for job-specific applications and are not addressed. Full-bodied manifolded (double suction) pumps and unmanifolded end suction (single-suction) pumps have different characteristics. Both are used in midship and rear applications. Apparatus or pump design engineers are the best resources for “which pump to use where.”

Except for operational requirements to draft at maximum capacity, a pump’s physical location is irrelevant. The closer a centrifugal pump impeller is to the water, the more efficient the pump will draft. Midship pumps drafting from auxiliary front or rear steamer suctions are not going to achieve maximum efficiency. Ask the apparatus and pump manufacturers or have salespeople substantiate claims with documentation. Requesting certified flow tests by an independent third party (i.e., Underwriters Laboratories) separates fact from fiction and ensures compliance. Add the requirement to purchasing specifications. Some purchasers are content to draft limited gallonage through front and rear steamers in scenarios where tanker relays may not sustain a pumper’s rated capacity. Just remember, you’re limited to that reduced flow from draft forever.

The location of end suction pumps is immaterial if always supplied from a pressurized water source. They usually terminate with a four-inch discharge that can be piped to wherever the discharge manifold or operator’s panel is desired and not necessarily in the same location. Some naysayers claim rear pumps “throw off the weight balance” on a pumper. Requesting certified weight certificates of delivered units will substantiate or disprove verbal claims. With today’s computer-generated weight and balance software programs, engineers can easily calculate weights for proposed units with pumps in alternative locations. Just ask.

Unfamiliarity and disinterest are possible reasons salespeople and manufacturers (OEMs) don’t promote rear pumps. Financial is another reason. If 95 percent of an OEM’s pumper production includes midship pumps, a rear or front mount in the assembly line could reduce efficiency and add labor hours, increasing cost. Having to fabricate a nontraditional body design could contribute to OEM angst toward the concept. From my limited exposure with them, I have found rear-mounted pumps allow shorter wheelbases with comparable compartmentation.

Midship and rear pumps can be powered by a split drive shaft arrangement in the chassis driveline or via power takeoffs (PTOs). Early PTO-driven volume pump installations were constrained by PTO “life expectancy” and horsepower limitations. Previous bad press, justified or not, is hard to overcome. Today, 1,500 gallon-per-minute pumps are regularly PTO powered. Skeptical? Ask vendors to explain continuous duty and heavy duty in PTO applications and if PTOs have to be replaced or tested after so many hours of actual usage. Europeans have been using rear pumps, albeit not high-volume, for eons. Critics claim they’re just another European fad. Other European “fads” include fully enclosed crew cabs, sexless couplings, roll-up doors, rear-mounted aerial ladders, and large-diameter hose.

If the pump operator’s (PO’s) panel location is the actual objective of this FA Viewpoints topic, I offer continued biased opinion. Discharges, inlets, crosslays, speedlays, and any pressurized hose connection do not belong on, above, or in close proximity to any PO’s panel – regardless of its location. It’s not safe – period. Limited staffing has forced POs to become an integral part of engine company operations. They can no longer remain stationary in front of the panel.

Top-mounted panels are advocated to keep the operator out of traffic and away from hoselines. However, each time a firefighter climbs on and off the rig is an invitation to a slip and fall – especially when hurried, more so in inclement weather. I disagree there’s always 360-degree visibility around on the rig with a top mount. Extraordinarily high body heights and raised cab roofs reduce front and rear visibility. Chassis wheelbases are also increased.

My thoughts on the top mount: After arriving on scene, you climb up to pull the tank suction and recirculate water; back down it to ensure a rear preconnect has cleared the bed; back up to charge it; back down to secure a water supply; back up to open the suction valve and change over and fill the tank; back down to eliminate kinks or help feed hose to the interior crew or perhaps pull a backup line; back up to charge it; and back down because someone has a problem with self-contained breathing apparatus or to do outside ventilation before the truck company arrives. I’ve never worked off one, but I imagine it’s like the stairwell evolution at the FDIC Firefighter Combat Challenge. The PO position might not be suitable for those with even minor physical limitations, too many years on the job, too much pasta intake, or an “older” date on their driver’s license.

PO panels at the rear of the rig are just as hazardous as midship panels if there are hose connections on or above it. I prefer a panel void of hose connections that’s located on either side of the rig behind the rear axle. That’s where the work is. As mentioned, an end suction pump can be piped to wherever you want. You have better overall fireground visibility. Look around the corner to see if the rear preconnect cleared its beds. Eight feet away, you can see the rig’s other side. Laid a line in? It’s easy to see the hydrant man. Reverse lay? Look down the street to see if the crew’s ready for water. When parked beyond the structure or after laying out, you’re well-situated to monitor changing fireground conditions and if your crew needs help. POs are the “go to” people to locate and retrieve equipment. Keep them on the ground where both the equipment and the pump panel are readily and safely accessible. Can you find any faults with a side PO panel located behind the rear axle?

Regardless, pump panel location will be a moot subject in the future. It’ll probably be some handheld remote control device or a heads-up electronic display in a helmet that’ll turn things on and off whenever you just “think about it.”

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.

Side Mounts Preferred

At one time, the location of the pump panel on your fire apparatus was a topic as contentious as the smooth bore/fog nozzle debate – okay, maybe not that bad, but it was a hot topic. Fortunately, I get to express my viewpoint as the advocate for the side-mounted pump panel.

Most of the apparatus that I have had the experience of operating were engines with side pump panels. And in my years of operating these engines, even the side-mounted pump panel has evolved from a wide, spaced-out area to a compactly designed pump mechanic’s nightmare. As the side pump panel area has become small and compact, it has become an efficient and well-planned-out area of the apparatus. This makes the functions of the panel very ergonomic for the pump operator. By designing the panel in this compact fashion, the manufacturers have reduced the width of the pump panel to as small as 45 inches. This size pump panel helps departments with the ever-consuming concern of the apparatus wheelbase. This reduction of the wheelbase and overall length is my number one factor in favoring the side pump panel.

It is rare that departments’ geographic response area is made up of wide spacious roads and ample turning areas. This reduction in wheelbase size helps with apparatus maneuverability in the response district. The top-mounted pump panels add extra length to the apparatus with the added walkway area, which can be 15 inches or wider to facilitate the operator’s movement. Regardless of the improved cramp angles on fire apparatus front axles today, this added length will affect the rig’s driving abilities.

Another advantage in operating from the side-mount pump panel is that the pump operator is operating from one consistent level. This enables the driver to operate the pump, make all the hookups, and assist on the fireground without having to constantly climb up and down from the pump panel area. With today’s short-staffed engine companies, the driver/operator assisting the officer and firefighters is crucial to the success of the company on the fireground.

I fully understand the safety of the top-mounted pump panel with regard to getting the operator in a position off the street and roadways. But, I believe with proper apparatus positioning and use of the traffic incident management system, side-mount panels can have some level of the same safety. The top mount does have an advantage of a better view of the incident, but I do not believe that those two supposed advantages outweigh the operational advantages of shorter wheelbase, maneuverability, and versatility.

Obviously, I am a proponent of the side mount, but that does not mean that my preference for this style will fit the needs or safety of your department. It has certainly worked well for me and the departments that I have been affiliated with. When making your choice of location for the pump panel on your next engine, take the time to consider all options before making your final decision – and then get a side mount!

RICKY RILEY is the fire apparatus manager for the Prince George’s County (MD) Fire/EMS Department. He previously served as the operations chief for Clearwater (FL) Fire and Rescue and as a firefighter for Fairfax County (VA) Fire & Rescue. He also currently serves as the rescue-engine captain at the Kentland (MD) Volunteer Fire Department. He is a member of the editorial advisory board of Fire Apparatus & Emergency Equipment.