The process of specifying and purchasing fire hose may seem simple, but it can get quite confusing and complicated when you start looking further into it. Over the past five years, I have been tasked to oversee the purchase, testing and replacement of fire hose in our department. Where we previously had fire hose from the early 1970s still in service, we now have a standardized color-coding system for each of our two fire companies, uniform brands and models of hose, a replacement plan that gives consideration to the recommendations of NFPA 1962 and annual testing of hose conducted by a reputable testing company. It took a few years to accomplish this, but the insights condensed into this article will hopefully help your department get its hose inventory to a point where you feel comfortable with its age and condition and can create and execute a reasonable replacement plan.
Specifying & Buying
Frontline firefighters trust their lives to fire hose, so it’s important that the end user thoroughly research several factors prior to purchase. These factors include more than just budget–you must consider the construction of the hose and the materials used, durability, kink resistance, ease of cleaning, packing and storage, as well as new NFPA standard updates. Remember: At the end of the day, all hose is not equal.
Before we discuss the finer points of specifying and purchasing, it is important to get an overall idea about how we view and classify fire hose. For simplicity, fire hose can be broken into two general categories: supply and attack. Some large diameter hose (LDH) is dual-purpose and marketed as such, but attack hose is typically found in diameters from 1—2.5 inches, while supply hose is typically 3 inches or greater in diameter. Most LDH supply hose used in the U.S. is single-jacket rubber hose. Fire hose rated for dual purpose (supply/attack) is typically found in the 3″-5″ diameter range and is double-jacket, rated for pressures of 300 psi or greater.
Diameter Variance
First and foremost, it’s important to understand the diameter of the hose before making a purchase. Current standards allow manufacturers to provide fire hose of varying internal diameters which may not be identical to the diameter stamped on the outer jacket. For example, 1¾” hose can actually have an internal diameter greater than the stamped diameter, due to the language set forth in the standards. Additionally, depending on the construction of the hose, some radial expansion may occur, resulting in a larger internal diameter under pressure. If you want hose true to its diameter, be sure to specify it. Testing done on various brands of 1¾” fire hose has shown internal diameters upwards of 1.84-1.89 inches and larger. These diameter inconsistencies make the purchase of equivalent brand/model hose and the use of hose-specific pressure loss formulas very important. For example, some hose manufacturers offer plastic pocket cards showing pressure loss data, which can be very helpful for training and on scene. If you think a handy guide to friction loss would help your department on the fireground, ask if the manufacturer offers pocket cards.
Jacket Selection
Another consideration is the type of jacket you want the hose to have. There are two common types for modern hose–rubber jacket and woven jacket. Fire hose of the past had jackets woven from natural fibers, often cotton with a rubber lining. While this hose is still used for some forestry and utility applications, it is not likely to be used for structural or municipal firefighting due to its lack of durability and a tendency to rot if not properly dried. As such, this article will focus on fire hose with synthetic woven or rubber jackets.
Synthetic woven jacket hose is available in nylon and polyester. Nylon is known to be a strong thread, but it often requires abrasion-resistant coatings to protect it from damage and burn-through. Polyester is typically a bit more durable and budget friendly, as it can be specified without an abrasion-resistant coating. In most instances, if colored hose is desired, it will require that the hose is coated with the abrasion-resistant coating, as the thread itself is not colored. The type of yarn weave will also impact the hose in its flexibility, as well as kink resistance. When reviewing manufacturer’s literature, you may ask about the type of yarn and weave and how it relates to the ability of the hose to resist kinking and remain flexible. Look at some of the better performing hoses that have high kink resistance, and compare the actual construction.
In addition to the type of jacket, fire hose is available in single- and double-jacket. Single-jacket hose is typically used for supply hose (rubber) and forestry hose. Some manufacturers offer single-jacket “high rise” hose, undoubtedly in response to the weight of the hose when it is packed into bundles. In my experience, however, the weight of the hose isn’t typically the issue when used in bundles; it is more a matter of how much hose is packed. There are many different ways to pack hose into easily-carried and deployable bundles, rather than sacrificing an outer jacket which results in hose that will be more susceptible to damage from abrasion and heat. I find it troublesome that firefighters would be comfortable carrying hose that has less redundancy so far away from their rig and into an environment that is incredibly dynamic. For these reasons, I have always been an advocate for the use of double-jacket hose for standpipe operations.
Liner Options
There are several options for fire hose linings. The most common three are: ethylene propylene diene monomer (EPDM), thermoplastic and impregnated/extruded polyurethane or nitrile rubber.
EPDM is typically the most budget-friendly liner, applied by adhesive to the inner jacket. EPDM liners are widely used in fire hose, yet as with any adhesive-applied liner, they can be subject to delamination over the life of the hose. Routine hydrostatic fire hose testing does not do much to detect this deterioration, and since there is no easy way to inspect the inside of a hose, the only way to verify the hose is holding up is to flow test it. This may be an easy endeavor for a small department who has a smaller inventory of fire hose, but may be much more difficult for larger departments, due to the massive amounts of hose in use.
Thermoplastic liners are also applied by adhesive. They offer a slightly lighter-weight liner that can be less prone to degradation, but they are also known for higher friction loss characteristics and may be subject to faster burn-through. Thermoplastic liners are also are not able to stretch as easily as EPDM liners, and are therefore more likely to delaminate over time.
Extruded or “through the weave” liners are becoming more popular on the market; several manufacturers now offer high performance attack hose with this type of liner. During the manufacturing process, the liner is applied in a liquid state to the fabric and seals itself to the inner jacket, resulting in a virtually inseparable hose liner. Another advantage of this liner is that it offers a more hydraulically efficient waterway. Extruded liners are essentially made by using the same process as single jacket rubber supply hose is, where a thread weave molded into the rubber gives it the strength to withstand pressure. This is a double-edged sword, however, because the improved flow qualities also mean that the friction loss values typically assessed by firefighters, pump operators and instructors are significantly different than the actual flow performance of the hose. The best way to see how the hose is performing is to conduct field testing with calibrated flow test equipment.
Coating
Protective coatings are a good option to protect the hose from things like abrasion, hot embers and pickup of extra water and other fluids like oils or hazardous materials. The coatings typically give the hose its color as well. If you desire colored hose, it will likely come with coating and add some extra cost. With different materials used for the coatings, you can expect that each brand or model of hose may have a different feel, and it may roll and pack differently than other brands or models. I have worked with brands that roll and pack like cardboard, and others that are so supple you can easily roll and pack them tightly. The coatings are applied to the hose after it is constructed, and in some cases they are baked on. One manufacturer runs the hose through rollers as it is coated to forcibly impregnate the coating into the hose. Though a bit more expensive than coating, colored yarn is also used to create tracer stripes in some models of hose, so that different colored stripes can indicate the different hose diameters or be used to color code the hose in a system of the end user’s preference. When specifying colored hose with a different colored stripe, remember that the color coating applied after the hose is woven will change the tint of the woven tracer stripe.
Length
The length of the hose should be carefully considered prior to purchase. For attack hose, the most common options are 50 and 100 feet. Two 50′ lengths will always cost a bit more, as there is an extra set of couplings required when compared to a single 100′ length. Proponents of 100′ lengths often cite cost effectiveness as well as the absence of an additional coupling, which can cause a snag problem when going around corners. I advocate for 50′ lengths, however, as they are easier to roll and store, and they allow for more flexibility when breaking or extending hoselines during stretches. Though not as common, 75′ lengths are available, and I have commonly found these used in high-rise bundles, where two lengths create a single 150′ hose load.
Supply hose is a different story. When using 3″ hose, it’s typical to see 50′ lengths, as this line is also regularly used with leader lines. Having 50′ lengths makes stretching, breaking and operating the lines easier for the members tasked to perform it. Larger diameter supply line (3.5—5 inches) is often best specified in 100′ lengths, as the absence of the extra couplings can provide a notable increase in total hose carrying capacity in a hosebed. The best way to address breaking these longer 100′ lengths when they are too long is to have at least one 50′ and one 25′ “pony” section of the supply hose. Ideally, carrying two of each offers greater flexibility, especially when your engine companies are connecting to four-way valves or connecting multiple supply lines to the rig.
Hose Fit
Because there are wide variations in width and thickness from one hose manufacturer to another, a final and important issue to consider is how the hose will fit in the intended hosebed(s), wells and/or troughs. A volumetric calculation can be used to determine the amount of fire hose that will fit within a given space. This calculation works within a volume perspective, but you must consider the flat width of the hose when determining the size of the beds, how many dividers to install and how far apart to space them. Ask your apparatus vendor to show the desired hose loads in a CAD drawing and make sure you provide them with the flat widths of your hose. For a department switching brands or diameters of hose, always make sure to measure the hosebeds or wells prior to purchase so you don’t have to make adjustments to the rig after the fact. Get the flat hose width and the coupling “bowl” diameter from the hose manufacturer as well. For example, 2″ hose with 2 ½” couplings has couplings that end up being wider than the hose, when laid flat. This causes storage issues in hosebeds if not taken into consideration.
Other Tips
Your best resources when specifying and buying hose are your local fire equipment vendors. They’ll often have hose samples to evaluate, including “cut-away” samples that show the hose construction and materials. You may even be able to obtain a full-length hose to test its fit and see how easy it is to work with. Don’t hesitate to contact the manufacturer directly, either. Many companies will meet with you, drop off demo hose and help you evaluate it. Just make sure that you compare brands fairly during this process, and ask the representatives for more information. Sometimes sales or spec sheets lack specific info that helps you compare the product to another brand.
Find out if the manufacturer tests each assembled length of hose, and to what pressure. Ask them if they are willing to supply proof of this testing. Some manufacturers may not test the hose after the couplings are applied. Also beware of fire hose “outlets” or bargain deals. They may be obtaining imported hose or buying it from other vendors and rebranding it. Ask about company history, materials origin and manufacturing location and processes.
Be familiar with your local requirements and laws when it comes to purchasing. If you are tasked with soliciting three quotes, for instance, try to find three vendors who sell the same brand of hose, so you won’t end up comparing quotes from different manufacturers or having a mishmash of hose on your rigs. You can also ask for shipping costs to be quoted separately, so they don’t muddy the actual hose prices. Don’t forget to compare warranties and fine print; you’ll want to know what’s covered and what isn’t. With warranties, be sure to find out about the terms of “all inclusive” warranties, that cover any type of damage, delamination warranties and workmanship warranties.
Finally, devise a replacement plan. Despite annual testing, it can still be difficult to determine the effects of time and wear and tear on your hose. Your plan should consider the warranty, usage frequency, storage conditions and patterns of performance during testing. This strategy will impact firefighter safety and provide ease of budgeting.
Remember: There is no “one size fits all” fire hose. The important thing is to do your homework, make yourself knowledgeable and ask questions of your sales representative and the manufacturers. Doing so will help you achieve the goal of providing your department with the best quality, at the best price for the best possible life of the hose.
The author would like to thank Key Fire Hose and All American Hose for contributing information.
Sidebar – How NFPA Standards Impact Hose Selection
NFPA 1962 governs the care, use, inspection, testing and replacement of fire hose, nozzles and appliances, while NFPA 1961 covers fire hose construction. Become familiar with these standards to better understand the products. The current edition of NFPA 1962 put some notable changes into place, which could affect how you handle the testing and replacement of hose. Below are a few changes found in the new edition:
- Requirement to remove from service all fire hose manufactured prior to 1987
- Requirement to establish a replacement schedule which factors in the age, use and condition of the hose
- Testing pressures were increased to 300 psi on all attack hose, including those which may be used to supply aerial ladder master streams
- Flow testing of nozzles was included as part of an attack line ensemble
- Supply hose with non-threaded (Storz type) fittings must now be equipped with locks
