Don’t be fooled when selecting your fire hose


CarolinaFireJournal - Glenn Hamm
Glenn Hamm
04/21/2013 -

A vital element of a water delivery system, which cannot be overlooked, is the hose you select. Modern fire hose has improved tremendously. Therefore, many of “the rules” such as tip size in relation to hose diameter; maximum flow capabilities and fire hose friction loss have changed. In fact, it is now possible to get big water through one and three-quarter, two and two and one-half inch hose!

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Additionally, all fire hose is certainly not created equally! A thorough, objective comparison is vital when making a decision regarding your fire flow needs and water delivery system. Nozzles and hose must be considered as a package and must be evaluated as such in order to achieve the best results.

How The Hose Is Manufactured Is Important!

Modern fire loads have increased twofold since 1950. This has created a strong need to select nozzles that provide a much larger volume of water at lower pressures. As the fire service moves in this direction, we cannot allow our hose selection to be the weak link in the chain. Therefore, it is important to note that the quality of flow rates, the inside diameter of the hose, friction loss and kink resistance are not universal among fire hose manufacturers. Simply, not all hose is created equal.

Some of the one and three-quarter, two, and two and one-half inch hose manufactured today is much more prone to kinks at the lower nozzle pressures typical of a smooth bore or low pressure fog nozzle and tend to snap violently when the stream is whipped aggressively even at moderate flow rates. Now, this is not the fault of the nozzle as some firefighters think, but is a direct result of the way the hose is designed and manufactured.

Additionally, friction loss, especially at higher flows, can vary greatly between manufacturers. During a recent nozzle test we were able to flow 265 gallons per minute through one particular brand of one and three-quarter hose with a one and one-eighth inch smooth bore tip with only 48 pounds of friction loss in 100 feet. We then placed the other well known one and three-quarter inch hose brands under the same testing and evaluation. Some of these hoses had an excess of 130 pounds of friction loss in 100 feet! Again, all fire hose is not created equally!

In another case, a local department was sold two-inch hose by a sales representative for their high-rise packs. This was designed to replace their current one and three-quarter inch high-rise hose. When the department decided to evaluate new smooth bore nozzles for their high-rise pack, they were shocked to find that the two inch hose they had purchased had more friction loss per 100 feet length than their older one and three-quarter inch hose flowing 200 GPM!

Ultimately, the water delivery system is a firefighter’s lifeline. Therefore we must ensure that we are providing our firefighters a product capable of protecting the firefighter and providing enough water to extinguishing the fire.

If your fire department is purchasing hose in the near future, you should to consider the following:

  • Fire Hose Friction Loss
  • Inner tube or liner
  • Kink Resistance
  • Outer jacket material in terms of durability
  • Burst Pressure
  • Test your hose before you buy!

Have the manufacturer prove that their hose does what they promise.  If your one and three-quarter, two or two and one-half inch pre-connects are 200 feet, then evaluate 200 feet of hose from the manufacture or dealer that is trying to sell you. Do not just take their word for it. Test the hose in a training tower or burn building, not a parking lot — for kinking issues and fire hose friction loss using your nozzles — while flowing the GPM you normally flow on an interior attack line. If your department is looking at a target flow of 200 GPM for residential fire attack, then purchase hose that is designed and built to flow 200 GPM. As a driver engineer wouldn’t you rather pump that line at 125 PSI discharge pressure to get 200 GPM rather than 205 PSI?

Hamm serves the fire and rescue service as an Assistant Chief at Station 17, Newberry County Emergency Services and Dive Team Leader for Newberry County Emergency Services. Hamm also services the needs of the fire service as owner of Poseidon Fire Rescue Equipment (www.POSEIDONRESCUE.com). E-mail Hamm at [email protected] or call 803-924-7146.
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