|Ferrara's MVP design incorporates a high-flow 2,000-gpm Hale Qmax pump with maximized rear-body compartment space. (Photos courtesy of Ferrara Fire Apparatus.)|
By Dominic Colletti
Chief Brand Marketing Manager
A recent feature article caught my eye. It primarily discussed issues related to gallon-per-minute (gpm) sizing of major fire pumps on today's full size pumpers. The text contained several statements from apparatus suppliers that piqued my interest such as, "Larger pumps also bring potential problems with them…" and the 1,250- to 1,500-gpm range is a "settling point for municipal apparatus ...." Also, "A lot of different apparatus features benefit from moving and shrinking the pump compartment ...." Of concern is that statements like these may lead readers to believe that high-gpm pumps-i.e. 1,500-gpm on up-are no longer feasible and may be things of the past if purchasers require more rear-body compartment space.
At the risk of being politically incorrect, I say that additional compartment space and high-gpm pumps are both required. And, yes you can have both today.
Times are changing. No secret to anyone at this point is that the fire service has become more of an "all-hazards-response" type of organization. Emergency medical service (EMS), auto extrication, technical rescue, fire response, and so on are a few of the many specialties at which we excel. Kudos to apparatus manufacturers for incorporating input from end users regarding increasing compartment space. Without argument, the benefit that more compartment space brings, so we can carry all the "stuff" we need for all of the jobs that we do, is an important issue. Bravo-champagne and caviar for all. However, any suggestion that the use of and need for "big pumps" that move "big water" may be waning in the fire service is just downright offensive. It's time for a reality check.
Let me make it clear: Every fire chief and truck committee should buy the pump size that they need, based on their own analysis, not on what a pump salesperson or apparatus dealer would like them to buy. Be reminded, however, that although the average number of fires has gone down, the dollar loss has gone up. Many fire districts need to be able to move big water by using big pumps to limit large-loss fires.
The American Extravagance
Fire has been called an "American extravagance" because average Americans view it as posing little if any threat to them personally. It is a sad state of affairs today that the United States has one of the highest fire death rates of the developed countries in North America, Western Europe, and the Asia/Pacific region.
Besides the high toll from loss of human life from fire, dollar loss from fire has dramatically increased during the past several decades. According to the National Fire Protection Association (NFPA), there was an average of 1,934,600 fires per year with an average fire loss of $12.79 billion from 1990 through 1999 in the United States. From 2000 through 2009, there was an average of 1,586,700 fires per year with an average fire loss of $17.69 billion. All dollar loss figures are inflation-adjusted in 2010 dollars.
Nothing protects a community from mayhem like big water. Therefore, fire chiefs and truck committees who are specifying pumpers should consider maximizing gpm pump size; buying large-diameter hose; carrying big water application appliances; and using preconnected, high-flow portable monitors.
So, how much more money does it cost for a big pump-say a 2,000- over a 1,250-gpm-you ask? For a quick check, I telephoned a pumper product manager at one of the top five fire truck builders for his opinion on what today's "average selling price" is for a "middle of the road" new pumper equipped with each size pump. He said that the "average" for 1,250- and 2,000-gpm pumpers is $295,000 and $325,000, respectively. So, for about 10 percent more money, you almost double your gpm-handling capability.
Looking at it another way, if you are buying a new pumper, you are essentially paying money to move water. So if we divide dollars by gpm, we find the 1,250-gpm pump costs $236 per gpm, while the 2,000-gpm pump costs $162 per gpm.
When I see a new pumper, typically with a 330-horsepower (hp) or higher engine, equipped with a 1,250-gpm fire pump, I often ask the department why it did not have a higher gpm fire pump installed. Answers vary, but few are fact-based and some don't make sense at all. The fact is that most engines in this power class can provide enough power to drive a pump rated at 1,500 gpm or higher (see box on page 22). Why not equip the apparatus with a larger gpm pump, which would enable you to move more water, since you have already paid for the high-hp engine?
When purchasing a new pumper, choose a pump that will use all of the available horsepower provided by your chassis' engine and transmission. We often see very large diesel engines driving fire pumps that use only 1⁄3 to ½ of the engine's horsepower capability. The fire service pays good money for diesel engines with lots of power to move fire trucks from point A to point B. Why not put that power to work by choosing the right size fire pump to maximize delivery rates? That just makes good sense.
Rural and suburban departments that work with deep-lift drafting conditions or have static water sources with poor apparatus access should consider choosing a high-gpm pump to increase pump performance from draft.
The technical reason for this choice is simple. Vacuum at the impeller eye of a pump decreases as the pump reaches its maximum rated capacity. Thus pump performance, the ability to develop vacuum and draw water into the impeller eye, decreases.
This means that a 2,000-gpm-rated fire pump will maintain vacuum performance over a larger gpm window compared with a 1,250-gpm fire pump. Maintaining vacuum at higher flow rates is important when attempting to draft from deep-lift or difficult-to-access water supplies.
In one drafting test involving a 14-foot lift with a single 65-foot long six-inch suction hose, a 2,000-gpm pump moved over 50 percent more water than a 1,250-gpm pump under identical suction conditions-very impressive.
I hope this has shed light on some of the issues we face in the fire service today. In the end, only you can determine your apparatus needs. Should you decide you need additional rear-body compartment space and a high-gpm fire pump, demand both.
DOMINIC COLLETTI is the chief brand marketing manager at Hale Products. He is a former assistant chief and a fire instructor with more than 20 years of experience. He is the author of two books, The Compressed Air Foam Systems Handbook and Class A Foam-Best Practice For Structure Firefighters.