Coupling Accessories

A coupling reducer is a double-ended fitting that connects two fire hose couplings of different sizes within the same coupling standard. For example, a Storz DN75/DN52 reducer connects a 75 mm supply hose (Storz Ka 89 mm) to a 52 mm attack hose (Storz Ka 66 mm) at a branch divider — without the reducer, the two hose sizes cannot be directly connected.

Reducers are used at pump discharge points (where the pump outlet size differs from the attack hose), at branch dividers and Y-pieces (where a larger supply line feeds multiple smaller attack lines), and at hydrant connections where the hydrant outlet size does not match the supply hose size.

CA-FIRE stocks reducers for the following coupling standards: Storz from DN52/DN25 up to DN150/DN110; Gost DN70→DN50, DN80→DN70, DN125→DN70 and DN125→DN80; NH from 3"×2½" up to 5"×4"; UNI804 Type A→B, B→C, A→C; Barcelona 2½"→1½" and 2½"→1". Contact CA-FIRE for additional size combinations or non-standard reducers.

CA-FIRE Storz reducers are available in two main constructions:

AL Forging (full aluminium): both coupling ends and the reducer body are aluminium forging. Lightweight, suitable for portable fire hose applications and fire truck hose loads. The AL forging reducer is the standard choice for attack and supply hose reducers on fire service vehicles and in fire hose cabinet installations.

AL + CS Body (aluminium coupling ends, carbon steel body): the two Storz coupling ends are aluminium forging but the connecting reducer body between them is carbon steel. The steel body is heavier and more resistant to crushing or impact damage — particularly relevant for reducers used on permanently installed suction hose that rest on the ground or are stored in abrasive environments. The AL+CS construction is commonly specified for large suction reducers (DN110/DN75 and DN110/DN52) where the reducer may be dragged across concrete or rough surfaces during suction hose make-up. Available in SZW75-52 and SZW110-75 size combinations.

The three gasket materials differ in their temperature range, chemical resistance and cost:

NBR (Nitrile Butadiene Rubber): the standard material for fire hose coupling gaskets worldwide. Temperature range −30°C to +120°C. Excellent resistance to water, seawater and most foam concentrates at standard fire system operating temperatures. Available in black (standard) and white (potable water applications). NBR is the correct specification for the vast majority of fire hose coupling applications — attack hose, supply hose, suction hose, hydrant connections and building fire hose cabinet systems.

Viton (FKM — Fluoroelastomer): for chemical service, petroleum-based foam agents (FFFP, protein foam), AFFF at high concentrations, and high-temperature applications. Temperature range −30°C to +200°C. Significantly more resistant than NBR to fluorosurfactants, fuels, oils and aggressive industrial chemicals. Green colour for identification. Specify Viton for chemical plant and petrochemical fire hose systems, foam monitor hose connections and any application where the hose may carry non-water fire suppression agents.

Silicone: for food-grade, pharmaceutical, potable water and cold-climate applications. Temperature range −50°C to +200°C. Best low-temperature performance of the three materials — specified for Arctic fire hose systems and for food plant fire protection where FDA food contact compliance is required. White colour.

For most fire service and building fire protection applications: use NBR black. For chemical or foam service: use Viton. For potable water or extreme cold: use Silicone.

The replacement interval for fire hose coupling gaskets depends on the coupling standard, service conditions and the inspection regime of the fire service or facility. As a general guide:

Annual inspection: inspect all gaskets for cracking, compression set, deformation, hardening or chemical contamination at the annual hose and coupling maintenance service. Replace any gasket showing visible deterioration — a failed gasket under operational pressure will cause leakage at the coupling face, reducing water flow to the nozzle and requiring the pump to work harder.

After each operational use: inspect gaskets for debris, damage or deformation caused by operational conditions — particularly on suction couplings where the gasket may contact grit or stones during drafting operations.

Preventive replacement: many fire services replace all coupling gaskets on a fixed schedule — typically every 3–5 years for NBR on operational hose — regardless of visible condition, as aged NBR can lose elasticity and fail during the pressure surge at pump start-up without showing obvious pre-failure signs.

CA-FIRE gaskets are available individually, in 10-packs and in 50/100-packs for maintenance kit supply to fire services and industrial fire protection maintenance contractors. Contact CA-FIRE for multi-pack pricing.

A suction strainer (also called a foot strainer or basket strainer) is a mesh basket fitted to the open end of a suction hose that is submerged in the water source during drafting operations. The mesh screens out debris — leaves, twigs, stones, mud and other solids — that could be drawn into the pump by the vacuum and damage the pump impeller, volute or mechanical seal.

The strainer attaches to the open suction hose coupling end using the same lug geometry as the hose coupling — a Storz strainer fits a Storz suction coupling, a Gost strainer fits a Gost coupling, and so on. The mesh basket is typically stainless steel (for corrosion resistance in open water) with an aluminium or brass body.

A suction strainer should be used whenever a fire pump is drawing water from an open source (river, pond, swimming pool, static water tank) — any time the suction end of the hose is submerged in open water. It is not required when the pump is connected to a pressurised mains water supply via a hydrant. CA-FIRE stocks suction strainers for Storz DN75, DN110 and DN150, BSRT 4", and Gost DN100 suction couplings.

To receive a quotation for coupling accessories, please provide the following when contacting CA-FIRE:

For reducers: coupling standard (Storz/Gost/NH/UNI804/Barcelona); size combination (e.g. Storz DN75→DN52); material (AL Forging, AL+CS, BR).
For blind caps: coupling standard; size or Ka dimension; material (AL/BR/ABS).
For gaskets: coupling standard; size; gasket material (NBR/Viton/Silicone); quantity (individual, 10-pack, 50-pack or 100-pack).
For wrenches and strainers: coupling standard and size; material preference.
For coupling clamps: coupling standard and Ka dimension (Storz only).

Accessories can be ordered as part of a complete coupling schedule or as standalone items. Provide a coupling order or project schedule and CA-FIRE will identify and include the correct accessories automatically. Contact CA-FIRE at sales@ca-fire.com, via WhatsApp, or via the contact page. Response within 24 hours.