A Hose is a Hose—Or is it?
For as long as 1 can remember, the fire service has been trying to standardize hose threads. Many large metro-departments use a special thread that is often adopted by other departments in the surrounding urban area. Many departments in industrial locations have iron pipe thread, and adjacent departments decide to follow suit. Smaller city departments often specify their own thread.
Because there is a great need for fire departments to assist each other, mutual aid associations have initiated the movement for national standard thread. The use of sexless couplings on large diameter hose also has encouraged standardization.
Now, in that long-lasting “tradition” of the fire service—never agree with another department—we cannot agree on what we call hose.
Do we call it attack lines, preconnects, or discharge lines? Is it a feeder line, gutter line, hydrant line, quick water, relay hose, or supported or unsupported supply line? When does a supported supply line become a relay?
Do we lay in, forward, or straight, lay out, back, or reverse? What is a split lay? Is a supply line an intake hose? Where does large diameter hose fit?
Is there a difference in a backup line, safety line, and a protection line? And, is it hard suction, hard sleeve, noncollapsible intake hose, sucker hose, or soft suction, soft sleeve, collapsible intake hose, or pony suction?
Confused? So am I!
Everyone has his own mental picture of these terms. There are formal definitions in various texts and in the National Fire Protection Association (NFPA) Standard, 1961, Fire Hose. The real question is: When and how will the fire service agree on and use commonly acceptable terms for hose?
The incident command system’s use of “clear text” is an attempt to introduce some common terminology. However, it too has problems. For example. most of the fire service in the United States and Canada still thinks that a tender is part of a steam locomotive, not a mobile water supply apparatus usually known as a “tanker.”
1 find several of the above terms to be synonymous. If so, should we use the one that is most technically correct or the regional term for wherever we are? Also, who or what body should determine the standardized terms?
Here are my definitions of some (I probably missed a few) hose terms.
Attack, discharge, and preconnected lines are all the same. They are the hose lines that are stretched from the discharge side of the pump to the nozzle or to the appliance used to attack and extinguish the fire. These lines may be of various types of construction and size, but they should be properly tested to make sure they will be able to withstand the pressures to which they will be subjected. Hose used for larger attack lines (2 1/2 -, 2 3/4-, and 3-inch) may also have other uses and, thus, other names.
A feeder, gutter, hydrant, quick water, or unsupported supply hose are all the same regardless of size, although 2 */2 -inch should be the minimum. These hose lines bring water directly from a water supply to the engine company at the fire. This operation generally is referred to as a forward lay or laying into the fire.
A short relay or supported supply line places an engine at the hydrant to pump the water via the water supply engine or pumper to the attack pumper or wagon. A supported supply line or tandem pumping (one engine behind the other similar to tandem axles) is most often 500 feet or less in length and uses smaller diameter hose.
Relay lines are two pumpers working together in the same lay with a great distance—usually 1,000 feet or more—between the units. In theory, the maximum distance between the pumpers is limited by hose diameter, flow requirements, and safe working pressures. In reality, the determining factor is usually the amount of hose carried by the responding engines.
A reverse lay or laying out is when the engine goes from the fire to the water source. It can also be when a water supply pumper lays from the attack pumper (wagon) back to a water source. A split lay is a combination of the two lays forward and reverse— when two pumpers establish a longer supported water supply as in a relay.
An intake hose is any line coming into the intake of the pump, usually called the suction side of the pump. It could be large diameter hose equipped with a pressure relief device, supported or unsupported supply lines (by any name your department calls them), or a short hose line connecting directly to a hydrant. This is all rather basic, but there are so many different terms that it becomes confusing.
The terms back-up line, protection line, and safety line are all different. A back-up line provides a water supply from a second source. It “backs up” the initial supply in case there is a failure anywhere in the overall system, i.e., source, hose, or pumpers.
A protection line is a hose that discharges water on or in front of an attack crew to protect them as they make their attack.
A safety line is a standby line that is fully manned and charged. It will assist the attack crew if they get in trouble. Ideally, it should be from a second pumper and source of water, although this is not always possible. You can use the safety line as a second attack line or a protection line. It should be a larger diameter hose line so it can also be used to cover the attack crew in the event of retreat.
A hard suction, hard sleeve, sucker, or non-collapsible intake hose are all the same. Although term usage is somewhat regional, the most common one is hard suction. These hoses are used to draft, test pumps, and connect directly to a hydrant.
We use “sleeve” because, theoretically, a pump does not suck water in, but creates a partial vacuum that atmospheric pressure forces water into through the reinforced rubber hose.
Soft suction, soft sleeve, and collapsible intake hose are non-reinforced hoses used to connect directly to a hydrant. A “pony” is in this category, but has a smaller diameter. Hose construction can vary.
How does the fire service arrive at standard hose terms? I await your well documented and supported recommendations. In the meantime, choose terms for your department and clearly define them so all members are aware of local usage. This will avoid delays and confusion on the fireground.