NOR Couplings

A NOR coupling (also written NOR fitting or Norwegian fire coupling) is a fire hose quick-connect fitting developed to Norwegian standard for use in fire fighting and high-pressure flushing applications. The NOR system uses a symmetrical locking ring design — both halves of the coupling engage by pressing together, and the outer locking ring rotates to produce a positive, vibration-resistant connection.

NOR couplings are primarily used on Norwegian-flagged and Scandinavian vessels, offshore oil and gas platforms in the Norwegian North Sea sector, and coastal port facilities in Norway and Scandinavia. They are also specified on vessels operating in the North Sea under NORSOK standards and on projects where the Norwegian flag state or classification society specifies Norwegian fire protection standards.

Beyond Norway, NOR couplings are found on vessels and platforms worldwide wherever a Norwegian owner, operator or class society has specified them. CA-FIRE manufactures NOR couplings in three lug sizes — LAS1, LAS2 and LAS3 — in aluminium forging and brass forging. The full firefighting couplings range is available on our overview page.

LAS1, LAS2 and LAS3 refer to the three lug-diameter sizes in the NOR coupling system. These sizes are not interchangeable — a LAS1 coupling will only connect to another LAS1 coupling, and so on.

LAS1 — Lug Ø 83 mm: the largest NOR size, used on main fire hose lines and primary attack hose. Hose tail sizes up to 75 mm bore. BSP thread range G1" to G3". Most common on vessel main deck fire stations and pump discharge connections.
LAS2 — Lug Ø 66 mm: mid-range NOR size for secondary fire lines, interior fire stations and hose reels. Hose tail sizes up to 51 mm bore. BSP thread range G1" to G2-1/2".
LAS3 — Lug Ø 50 mm: smallest NOR size for small-bore hose reels and lightweight attack hose. Hose tail sizes up to 42 mm bore. BSP thread range G1" to G2".

When specifying NOR couplings for a vessel or offshore project, the lug size for each fire hose station will be defined in the vessel's fire safety plan or the project's fire protection specification. Always confirm the lug size before ordering — CA-FIRE can advise based on project documentation.

The 60 bar (870 psi) pressure rating of NOR couplings reflects the requirements of marine and offshore fire systems, which typically operate at significantly higher pressures than land-based fire hose systems.

On a vessel or offshore platform, fire pumps are sized to deliver water at adequate pressure to all parts of the vessel simultaneously — including elevated decks, engine rooms below the waterline and remote sections of large platforms. Fire pump discharge pressures on vessels commonly exceed 10–15 bar at the pump outlet, and pressure losses through long hose runs, height differences and flow through multiple outlets can require pump pressures far higher than the 6–8 bar typical of a land-based fire hydrant system.

Additionally, many vessels use Jockey pumps (pressurisation pumps) that maintain the fire main under constant high pressure so that any hose station can be opened immediately without waiting for a pump to start. These systems commonly operate at 10–16 bar continuous pressure, with fire pump surge pressures potentially reaching 20–30 bar or higher.

By contrast, standard land-based couplings — Storz, BS336, Barcelona, Gost — are typically rated to 16 bar, which is sufficient for municipal fire hose pressures but insufficient for many marine fire system operating conditions. The NOR 60 bar rating provides a substantial safety margin across all credible marine fire system pressure scenarios.

NOR to BSP thread: CA-FIRE manufactures NOR female thread (NOF) and NOR male thread (NOM) adaptors in all three lug sizes, with BSP thread sizes from G1" to G3". These allow NOR-coupled hose to connect to BSP-threaded pump outlets, nozzles, spray tips and hydrant landing valves — the most common connection requirement on marine projects. A NHT (National Hose Thread) version of the LAS1 male adaptor is also available for North American projects.

NOR to Storz: NOR and Storz use different connection geometries and are not directly interchangeable. A mixed NOR × Storz adaptor — NOR coupling on one end, Storz coupling on the other — can be manufactured by CA-FIRE for projects requiring compatibility between the two systems (e.g. a Norwegian vessel with both Norwegian and international hose inventories). Contact CA-FIRE for custom adaptor requirements.

NOR to BS336: Similarly, NOR × BS336 mixed adaptors are available on request for vessels operating under both Norwegian and UK flag state requirements, or for projects where quayside BS336-coupled shore fire water supply must connect to a vessel's NOR-coupled fire main.

Both aluminium forging and brass forging NOR couplings are rated to 60 bar and are dimensionally interchangeable — an aluminium LAS1 coupling will connect to a brass LAS1 coupling without any fitting issues.

Aluminium forging NOR couplings are lighter and are the standard choice for portable fire hose on vessel fire stations. The weight saving is significant when a crew member must carry and deploy fire hose rapidly in an emergency. Aluminium is suitable for fresh water and standard seawater service in most marine environments, particularly when the coupling is not in permanent contact with the sea.

Brass forging NOR couplings are heavier but provide superior corrosion resistance for permanently installed connections, external deck fire hose stations exposed to continuous seawater spray, and installations in the engine room bilge area where salt contamination and condensation are continuous. Brass couplings are the preferred choice for fixed, permanently installed hose connections on vessels in tropical and highly corrosive marine environments.

For class society approval on vessel projects, both materials are acceptable. Some vessel owners specify all-brass for permanently installed connections and aluminium for portable hose stocks to achieve the best balance of corrosion resistance and operational weight.

When specifying NOR couplings for a marine or offshore project, the following information is required to place an accurate order with CA-FIRE:

1. Coupling type — hose tail (NOH), female thread (NOF), male thread (NOM) or blank cap (NOC).
2. Lug size — LAS1 (Ø83 mm), LAS2 (Ø66 mm) or LAS3 (Ø50 mm) as specified in the vessel's fire safety plan or project specification.
3. Hose tail bore — internal diameter of the fire hose in mm (for hose tail couplings).
4. Thread specification — BSP thread size (G1", G1-1/2", G2", G2-1/2", G3") for thread adaptors.
5. Material — aluminium forging (AL) or brass forging (BR).
6. Quantity — pieces per line item.
7. Documentation requirements — material test certificates, dimensional inspection reports, pressure test certificates, class society approval documentation.

CA-FIRE can provide full technical documentation suitable for vessel class society submittals. Contact us at sales@ca-fire.com or via WhatsApp with your project specifications. We respond within 24 hours.