Overview
EN ISO 7840:2021 (ISO 7840:2021) specifies requirements and physical tests for fire‑resistant fuel hoses used in permanently installed fuel systems of small craft. The standard covers hoses for conveying petrol (including ethanol blends) and diesel (including FAME blends) and defines construction, performance and test methods to reduce the risk of fire and fuel leakage in recreational and other small watercraft up to 24 m hull length. It supersedes EN ISO 7840:2018 and provides a harmonized route to conformity with safety requirements of Directive 2013/53/EU where applicable.
Key topics and technical requirements
- Scope and limits
- Applies to permanently installed fuel hoses (not hoses entirely within the stern splash well connected directly to outboard engines).
- Working pressure limits: 0.34 MPa for hoses with inner diameter ≤ 10 mm; 0.25 MPa for hoses up to 63 mm inner diameter.
- Materials and construction
- Hoses must have a non‑porous, smooth inner surface free from defects and chemical contaminants.
- Tube (inner liner) and cover (outer jacket) defined for fuel contact and weather/ozone protection.
- Physical tests (finished hose)
- Bursting pressure, vacuum‑collapse, volume change, mass reduction, cold‑flex, abrasion, dry heat resistance, oil resistance, adhesion.
- Fire resistance test (Annex A - normative) to verify hose performance under fire exposure.
- Fuel permeation requirements and test method (Annex B - normative), including provisions for low‑permeation hoses (newly emphasized).
- Ozone resistance assessment.
- Marking and conformity
- Marking requirements and reference to presumption of conformity with EU essential safety requirements when cited in the Official Journal.
Practical applications and users
- Who uses EN ISO 7840:2021:
- Hose manufacturers for product design, testing and certification.
- Boat builders and marine engineers specifying fuel system components.
- Test laboratories performing the normative tests (fire, permeation, burst, etc.).
- Regulatory authorities and certifiers assessing compliance with recreational craft directives.
- Procurement/specification teams selecting compliant fire‑resistant fuel hoses.
- Practical value:
- Ensures fuel hoses are safe for use with petrol/ethanol and diesel/FAME blends.
- Reduces fire and vapor risks on small craft through validated fire‑resistance and permeation performance.
- Supports regulatory compliance and consistent product quality.
Related standards
Keywords: EN ISO 7840:2021, fire-resistant fuel hoses, small craft fuel systems, fuel hose fire test, fuel permeation, FAME, petrol and diesel fuel hoses.