Fire Hose Types: Jacket, Diameter, Pressure and Coupling Standards Explained

A 300 metre order of 2.5 inch fire hose arrives at a fuel terminal and is rejected at the gate. The hose is sound. The problem is the ends: the supplier shipped NH threaded couplings, while every hydrant and pumper on site carries Storz. Nothing connects, the plant loses a week, and someone pays for a second shipment.

That one mismatch explains why the question of fire hose types is never a single question. A hose is classified by four independent things: how the jacket is built, what duty it performs, its diameter and working pressure, and the coupling standard on its ends. The first three decide how the hose performs. The fourth decides whether it connects at all, and it is the one buyers most often leave until last.

Work through the four in order and the choice usually narrows to one or two catalogue items. Skip the fourth and nothing else matters.

Duty First: Attack, Supply, Suction and Wildland Hose

The fastest way to sort hose types is by the job it does, because duty sets diameter, pressure rating and construction at the same time.

• Attack hose: 1 inch to 2.5 inch (25 mm to 65 mm) inside diameter, working pressure typically 250 to 400 psi, built to be dragged, kinked and handled inside a structure.
• Supply hose: 2.5 inch to 6 inch (65 mm to 150 mm), working pressure usually 150 to 250 psi, carrying water from hydrant to pumper or pumper to pumper in a relay.
• Suction hose: rigid, rubber covered and helix reinforced, used on the intake side of a pump where pressure is negative and a normal jacket hose would collapse.
• Booster hose: 3/4 inch to 1 inch, hard rubber, mounted on a reel for small fires, washdown and overhaul.
• Wildland or forestry hose: 1 inch to 1.5 inch, lightweight, packed small and carried long distances on foot.

Pressure rating follows duty. A supply line that sees 150 psi at the pump does not need the burst strength of an interior attack line, and paying for that strength across a kilometre of large diameter hose is wasted budget.

Wildland hose also has its own connection family. Forestry lines are joined with external binding or internal expansion couplings rather than threads, because gloves, smoke and speed make threaded joints impractical on a fire line.

Internal Expansion Forestry Fire Hose CouplingThreadless forestry coupling that seals by expanding an aluminum ring, matching wildland fire hose connection practices.View Product →

Construction: Single Jacket, Double Jacket and Rubber Covered

Jacket construction is where cost meets service life.

Single jacket hose has one woven polyester layer. It is light, coils tightly and suits washdown, light industrial duty and wildland work, but it abrades faster and carries a lower burst pressure.

Double jacket hose has two woven layers. The second layer lifts burst strength and resists abrasion from concrete, gravel and sharp debris, which is why it is the usual choice for municipal attack lines.

Rubber covered and through-the-weave hose extrude an EPDM or similar compound through or around the weave. The jacket then resists abrasion and many chemicals, absorbs very little water and dries faster, a real advantage where hose sits damp in a cabinet for months.

Inside the jacket sits the lining: EPDM, nitrile, polyurethane or PVC. The lining sets friction loss, chemical compatibility and how the hose behaves after long storage. Nitrile and polyurethane generally handle oils and fuels better than standard EPDM, while EPDM copes well with heat and ozone.

Diameter and Working Pressure: The Numbers That Set Flow

Diameter changes flow more than pressure does. Friction loss climbs sharply as bore falls, so a 1.75 inch attack line and a 2.5 inch line at the same pump pressure deliver very different volumes; the smaller line trades flow for mobility. On the supply side, stepping from 3 inch to 5 inch large diameter hose can cut friction loss several times over, which is why terminals and refineries standardise on large diameter supply hose and use adapters to feed smaller attack lines.

Coupling Standards: The Part That Decides Compatibility

A hose is only as useful as its ends. Coupling standards exist because different countries and industries developed their own ways of joining hose, and they are not interchangeable in any direction.

Storz couplings are symmetric and threadless. Two identical halves lock with a quarter turn of the lugs, which makes them fast to connect in poor light and forgiving of alignment. They dominate large diameter supply hose in Europe and in industrial terminals.

Large Storz-Style Fire Hose CouplingLarge Storz-style coupling with serrated or ribbed tail ends for fire hose and industrial fluid transfer.View Product →

Machino couplings are threaded, with distinct male and female halves, and remain standard in Japan and in much of the equipment supplied to Asian markets.

NH, also called NST in North America, John Morris in the United Kingdom, Italian and C+E in Australia are all threaded families. Each has its own thread form, pitch and seat angle, so a 2.5 inch NH male will not seal into a 2.5 inch John Morris female even though the two look similar at arm's length.

Multi-tooth, VIC, flanged and grooved connections serve industrial pipework and mining, where a joint must stay made under vibration and be assembled with hand tools. Mining, agricultural, garden and sanitary drainage couplings extend the same logic into non-fire applications.

The practical rule is to match the coupling standard to the equipment already on site, not to the hose you prefer. If the shop floor needs the detail, this guide on how a fire hose joint should be connected walks through the assembly steps and the mistakes that cause leaks.

When Standards Do Not Match: Adapters, Reducers and Blind Caps

Adapters and reducers solve a mismatch without replacing a hose fleet. A Storz to flanged adapter connects large diameter hose to industrial pipework, Storz to forestry adapters let a municipal pumper feed a wildland line, and Machino to Storz or Machino to forestry versions bridge Japanese equipment and European supply hose. Multi-tooth equivalents cover the same ground on mining and industrial circuits.

Flanged Storz Adapter Couplings for Hose SystemsConnects Storz hose to flanged industrial pipework, helping bridge standard mismatches without replacing the hose fleet.View Product →

Keep the adapter count low. Every extra joint is another gasket to inspect and another place water can escape at 150 psi. Where a site runs two standards for years, it is usually cheaper to settle on one standard for bulk supply and keep two or three adapters in each cabinet for emergencies.

Matching Hose Type to the Job: A Short Checklist

1. Confirm the coupling standard and thread on every hydrant, pumper and appliance the hose will reach.
2. Match duty to diameter: attack inside a structure, supply over distance, suction on the pump intake.
3. Check the working pressure against the highest pressure the hose will actually see, not the average.
4. Check the lining against the fluids on site, including fuels, oils, seawater and foam concentrate.
5. Choose single or double jacket based on how often the hose is dragged over rough ground.
6. Plan storage: hose dried and rolled lasts years longer than hose left wet on a truck.

Procurement Details That Cause Rework

Most rejected deliveries trace back to a handful of specification gaps that are easy to close on the purchase order.

• Size given as a trade name only, without the measured inside diameter in millimetres.
• Ends described simply as a 2.5 inch thread, with no thread form, pitch or seat angle stated.
• Working pressure confused with proof or burst pressure, so the hose is ordered to the wrong grade.
• Coupling material overlooked: aluminium is light, brass resists salt water better, stainless suits aggressive chemical exposure.
• Gasket compound missed, even though EPDM, nitrile and silicone behave differently against fuels and heat.
• Test documentation requested late, when inspectors and insurers want reports tied to the delivered batch.

The type of fire hose you need is rarely a single answer. Fix the duty, then the diameter and pressure, then the construction, and finish with the coupling standard, because that last step decides whether the line works on the day.

Where a site runs several standards, or a project mixes municipal, forestry and industrial hose, it helps to work with a manufacturer that builds the joints rather than only the hose. Our production covers couplings, adapters, nozzles and distributors across the Machino, Storz, NH, John Morris, Italian, C+E, forestry, multi-tooth, flanged, mining and agricultural families, backed by ISO9001:2015 certification, voluntary product certification and inspection reports from the national fire equipment quality supervision and inspection centre. Send your coupling standard, diameter and working pressure through the contact page and we will confirm the matching parts.