Pumpers are vital to any fire department's fleet. They also can be among the most dangerous pieces of equipment in service. But what makes water-loaded pumpers so dangerous to drive?

The fundamental problem is that the water motion inside follows Newton's Third Law: To every action, there is an equal and opposite reaction. In other words, if a pumper carrying 1,500 gallons of water veers to the right, the 12,571 pounds of water it is carrying will go to the left, throwing the truck off balance. In the same vein, a pumper with a water-influenced center of gravity that is set high on its chassis will be prone to tipping during cornering.

Adding to this risk is the additional equipment carried on pumpers. If weight isn't distributed evenly, the truck can be imbalanced. In motion, a pumper with 1,000 pounds more on its left side that its right will tip leftward during right turns.

This is where NFPA 1901 comes in. Chapter 18 deals with pumpers specifically.

“The standard calls for water tanks to be baffled and partitioned both length-wise and width-wise,” says Lawrence Stewart, a fire service specialist with the NFPA's fire protection division. “The partitions limit the amount of water moving as a single force, while the baffles help dispel its energy when the water hits them. Together, they substantially reduce the reaction of the water to motion and turns, reducing the danger of weight-shifting and rollovers.”

Stewart adds that the partitioning and baffling standards for fire apparatus are different from those applied to commercial tankers that haul water, milk or oil. This is why converting such vehicles to fire department use is such a bad idea. “After all, a milk tanker was not designed to be driven under emergency conditions,” he says.

Center of gravity is another prime concern in NFPA 1901, because the lower a vehicle's center of gravity, the less prone it is to rollovers. For this reason, Pierce builds all of its pumpers to meet the 2009 edition of NFPA 1901. “To verify that they pass, we put them on tilt tables, fill them up and tilt the truck up to 26° to the left, then to the right, says Michael Moore, director of strategic sales development. “A lot of our pumpers are now sold with electronic stability systems. These monitor the actual weight distribution in the truck, using this data to prevent pumpers from exceeding their speed and corning capabilities.”

When it comes to deciding how much water and equipment a pumper should carry, “Be sure to follow the gross vehicle weight limits of the chassis,” says Rosenbauer's Harold Boer.

Also be sure that, “the chassis you have selected has large enough axles, power and ruggedness to handle its load,” says Jason Witmier, KME's pumper-tanker product manager. “Carrying capacity isn't the end of the story. It is vital to ensure that the weight is evenly distributed, so that the rear axle doesn't support most of the load. When this happens, the front wheels can end up losing grip on the road during high-speed turns, even in dry conditions.”

For the crew, a fully enclosed cabin with roll-cage construction, airbags and proper seatbelts are a must. So is rigorous enforcement of a buckle-up policy: Unbelted firefighters are frequently injured or killed when their vehicles get into accidents. Many modern pumpers come with seatbelt indicators on the control panel that let the driver and the commanding officer know who is following the rules.

Witmier says that the distribution of stored equipment has to be included in a pumper's overall weight equation. “Everything you carry has to be taken into account,” he says. “If you have 1,500 pounds on one side and 500 on the other, you've got problems even if the pumper was built properly balanced, with a NFPA-compliant partitioned, baffled and low-slung tank.”

The importance of keeping a running count of added weight is illustrated in this account from the National Firefighter Near-Miss Reporting System:

“… After extinguishing the fire, the crew began to back the engine from the parking lot. The truck had only moved a few feet when a loud boom was heard and the driver's front side of the vehicle dropped. All steering ability was lost. The leaf spring on the vehicle had broken in half. Had this occurred while the vehicle was in motion on the highway, there was high potential for a crash or vehicle rollover.… The vehicle is a large rescue pumper and was heavily loaded when it was delivered. Many pieces of equipment have been added in the 15 years we have owned the vehicle.… I'm guessing the vehicle is severely overweight!”

Outside, it makes sense to meet, if not exceed, the reflective coverings and other warning surfaces specified under NFPA 1901. In this vein, Rosenbauer is making its grab rails yellow because, “Yellow is more visible than chrome,” says Boer. “We are putting ladders onboard for taking down equipment, and making the truck's sign board raise above the vehicle to provide extra warning to drivers. Our pumpers also have a positive locking SCBA tank holder to keep bottles safely stowed, and power equipment devices to lower equipment from the truck down to ground level safely.”

“These are the kinds of features we are looking for when we buy new pumpers,” says Asst. Chief Travis Trent, Logan Rogersville (Mo.) Fire Department. “We want airbags, including curtain airbags, rollover protection and pre-tensioning on our seatbelts. We want the lowest center of gravity possible. We want our pumpers to be easy to get in and out of, and safe to use by keeping the hose connections away from the operator. This is why we buy our pumpers from the professionals, rather than trying to build them ourselves.”

Now it is possible to economize on pumpers by building them yourself. Likewise, you always could resort to jumper cables and a truck battery rather than carrying a proper defibrillator. But is this smart? In both instances, the answer is definitely no, as this near-miss report indicates:

“My crew was dispatched to assist a neighboring department with a brush fire. Our station's brush truck is a home-built retired military 6 by 6 with a 750-gallon water tank. This unit was specifically requested by the other department because their unit was stuck in a muddy area.… Our brush truck has an overhead screen and seats for two pump operators but no seatbelts. We pulled out onto the road and activated our siren and warning lights. Our emergency lighting consists of one magnetic mount mini light bar that is placed on the back of the tank, and one light bar on top of the cab. The switch that controls the light bar is not the right type, so you cannot run both lights at the same time. This had been noted in the daily inspection for several months. No corrective action had been taken. We approached the intersection where the two-lane road crosses the loop. This loop is known as the “Death Loop.” Due to our slow speed and lack of proper emergency lighting, no one recognized us as an emergency vehicle. Traffic started slowing and my driver started pulling out. I told my driver, ‘No,’ repeatedly but he was unable to hear me over the engine of the brush truck. We pulled out with an 18-wheeler approaching from the driver's side and a 1 ton pickup hauling a trailer on the passenger side. Both vehicles were doing approximately 65-75 mph at the time. Both vehicles had to take evasive action to avoid hitting our truck.”

According to the person who filed this report with www.firefighternearmiss.com, “This truck should be retired to second out status due to its slow speed and large size. Our department would be better suited with an interface-style truck on an appropriate size chassis.”

Whenever a department buys a pumper, it is at the mercy of whatever standards were in place when the apparatus was built. Stewart says, NFPA standards are being improved and revised by fire departments constantly, based on lessons learned from lives lost on the job. When a department buys used, it ends up with less-safe equipment, compared to what's being built today, as this near-miss report suggests:

“While seated in the left rear facing jump seat of a pumper during a fire response, I was attempting to don the breathing apparatus that is positioned in the seat back. I unbuckled my seat belt and reached behind me to obtain the waist strap of the SCBA. When I shifted position, my turnout coat caught on the lever of the door latch. The pumper went around a right hand curve and I fell out the door.… The apparatus operator saw the door come open in his left side mirror and brought the unit to a gradual stop with me hanging from the door. Only the apparatus operator's alertness and prompt effective action saved me from injury and possible death. Older apparatus with those lever-type door handles are still in service. I have never again allowed my seatbelt to be unbuckled while riding on fire apparatus.…”

In a perfect world, a department would have enough money to buy and operate only pumpers that meet the newest version of NFPA 1901. But when cash is tight, “there are lots of options available to fire departments in need of a new pumper/tanker ranging from financing options for new trucks to buying used trucks to refurbishing existing trucks,” says Moore. “When buying used trucks, they will more than likely not meet all existing NFPA standards such as the new stability requirements or ESC. Depending on age and condition of an existing pumper/tanker, the department may be better off refurbishing the truck rather than buying used. I recommend working with a local ‘full-line’ fire apparatus dealer to explore all options available and to develop a solution that best fits the department's needs and budget.”