Flame-retardant
CARBOCORD/EN 7840 A1
CARBOCORD/EN 7840 A1 is a fire-resistant fuel hose for boats and yachts. It meets ISO 7840:2018 type A1 and SAE J1527:2011 (USCG type A, class 1 and 2, style R1 and R2) and has the highest class of permeation resistance, meaning fuel escaping through the hose wall. The inner tube is black NBR, the reinforcement is a synthetic textile braid, and from 25 mm inner diameter upwards an embedded steel helix lets the hose work as a filling line and withstand vacuum. The temperature range is −30 to +100 °C. The hose comes in 12 sizes from 5 mm to 63 mm inner diameter.
- Fire-resistant
- ISO 7840 A1
- SAE J1527 / USCG A
- NBR inner tube
- −30 to +100 °C
- Marine fuel
Why this hose?
CARBOCORD/EN 7840 A1 is built for the part of the boat where a fire does the most damage: the fuel system. The hose is approved to ISO 7840:2018 type A1, the international standard for fire-resistant fuel hoses in small craft, and to the American SAE J1527:2011 (USCG type A).
Permeation is the part you cannot see. Fuel can slowly pass through a hose wall, and the vapours collect in the engine space. The hose meets the highest requirement for permeation resistance, so as little as possible escapes.
From 25 mm upwards the hose has an embedded steel helix. It keeps the hose open during filling and under vacuum, which is why the large sizes are used as filling hose from deck filler to tank.
Where it is used
In leisure boats, RIBs and yachts the hose sits throughout the fuel system: the small sizes as feed and return lines between tank, filter and engine, the large ones as filling hose and vent line.
Boatbuilders use it in new builds, and yards use it when replacing old fuel hoses.
In everyday talk it is called a fuel hose, boat fuel hose or simply a "7840 hose".
Technical specifications
Technical specifications for CARBOCORD/EN 7840 A1.
| Inner tube | NBR, black, smooth |
|---|---|
| Reinforcement | Synthetic textile braid, embedded steel helix for ID above 25 mm |
| Cover | CR, black; smooth up to 25 mm ID, fine fabric impression above 25 mm |
| Temperature range | −30 to +100 °C |
| Working / burst pressure | R1: 10 / 40 bar; R2: 2.5 / 14 bar |
| Max. vacuum | R1 5–10 mm: 0.8 bar; R1 12–25 mm: 0.7 bar; R2 16–63 mm: 0.7 bar |
| Standards | ISO 7840:2018 type A1; SAE J1527:2011 USCG type A, class 1 and 2, style R1 and R2 |
| Length tolerance | ±1 % (ISO 1307) |
Dimensions and ordering
The table shows the 12 standard sizes. 5–16 mm and 25 mm are style R1 with 10 bar working pressure. 19 mm and 32–63 mm are style R2 with steel helix and 2.5 bar working pressure. R1 comes in 20 or 40 m coils, R2 in 40 m coils.
| Inner Ø |
Outer Ø |
Wall thickness |
Burst pressure |
Bend radius |
Max. length |
Weight |
Roll |
|---|---|---|---|---|---|---|---|
| 5 | 13 | 4 | 40 | 20 | 40 | 0.15 | 20, 40 |
| 6.3 | 14.5 | 4.1 | 40 | 23 | 40 | 0.18 | 20, 40 |
| 8 | 16 | 4 | 40 | 25 | 40 | 0.2 | 20, 40 |
| 12.7 | 21 | 4.15 | 40 | 45 | 40 | 0.29 | 20, 40 |
| 16 | 25 | 4.5 | 40 | 65 | 40 | 0.38 | 20, 40 |
| 19 | 28.5 | 4.75 | 14 | 80 | 40 | 0.49 | 40 |
| 25 | 35 | 5 | 40 | 110 | 40 | 0.6 | 20, 40 |
| 32 | 42 | 5 | 14 | 128 | 40 | 0.96 | 40 |
| 38 | 48 | 5 | 14 | 152 | 40 | 1.11 | 40 |
| 40 | 50 | 5 | 14 | 160 | 40 | 1.16 | 40 |
| 51 | 63 | 6 | 14 | 204 | 40 | 1.7 | 40 |
| 63 | 75 | 6 | 14 | 252 | 40 | 2.14 | 40 |
Working pressure and vacuum are given under Technical specifications because they follow the style (R1 or R2). Wall thickness is calculated from inner and outer diameter. Bend radius is measured along the inside of the hose bend.
Standards and compliance
CARBOCORD/EN 7840 A1 is approved to:
- ISO 7840:2018 type A1. International standard for fire-resistant fuel hoses in small craft. Type A1 is the fire-resistant style.
- SAE J1527:2011. American standard for marine fuel hoses, USCG type A, class 1 and 2, style R1 and R2.
- Lloyd's Register Marine & Shipping. As stated by the manufacturer.
- ISO 1307. Length tolerance ±1 %.
Documentation and downloads
Additional documents about this hose, its compliance and installation. Click to download as PDF in a new tab.
Help with material selection
The hose is not antistatic and not ATEX-relevant, but these two articles give background on electrical resistance and grounding in hose systems, should that become a requirement in the installation:
The invisible weakest link
Why a conductive or antistatic hose isn't sufficient on its own — and what grounding means for the complete system.
Know your ohm
The difference between antistatic and conductive, which resistance limits apply where, and how to measure them correctly.
Industries that use it
CARBOCORD/EN 7840 A1 is used wherever fuel runs through a hose on board:
In boatbuilding and the yacht industry ISO 7840 is the international standard for fire-resistant fuel hoses.
With both ISO 7840 and SAE J1527 the hose covers the international and the American standard in one product.
Custom lengths and assemblies
The hose comes in 20 or 40 m coils and is cut to length. We fit couplings and supply finished assemblies. Minimum order quantity is 120 m.
For fixed annual quantities we agree delivery in full coils or pallets.
Frequently asked questions
What does ISO 7840 A1 mean?
ISO 7840 is the international standard for fire-resistant fuel hoses in small craft. Type A1 is the fire-resistant style, and the manufacturer states that the hose meets the highest requirement for permeation resistance, meaning fuel escaping through the wall.
What is the difference between R1 and R2?
R1 is the style without steel helix in the small sizes from 5 to 25 mm, with 10 bar working pressure and 40 bar burst pressure. R2 has an embedded steel helix and comes from 19 to 63 mm with 2.5 bar working pressure and 14 bar burst pressure. R2 keeps its shape during filling and under vacuum.
How much vacuum can the hose withstand?
The manufacturer states 0.8 bar for R1 in 5 to 10 mm, 0.7 bar for R1 in 12 to 25 mm and 0.7 bar for R2 in 16 to 63 mm.
How should the hose be stored?
Under ISO 8331:2016 rubber hoses should be kept cool, dry and dark, preferably between −10 and +25 °C and below 70 % relative humidity, at least 2 m from heat sources and away from ozone sources such as electric motors and fluorescent tubes. The hose should lie unconstrained, and the original packaging and end caps should stay on as long as possible. Use first in, first out.
Can you supply the hose cut and with couplings?
Yes. The hose comes in 20 or 40 m coils, and we cut it to length and assemble it with the couplings the installation requires. Minimum order quantity is 120 m.