ISO 13774:1998

Overview

ISO 13774:1998 specifies a laboratory method for assessing the flammability of rubber and plastics hoses (nominal bore 16 mm or smaller) intended for petroleum fuels used in internal‑combustion engines. The test exposes a fuel‑filled hose assembly to an open flame (heptane) and records the time to leakage. This standard is intended to verify that hoses do not fail by leakage prematurely when exposed to fire under controlled conditions.

Key topics and requirements

• Scope: Hoses for fuels for internal‑combustion engines with nominal bore ≤ 16 mm.
• Reference: Conditioning and environmental requirements are referenced to ISO 471:1995 (temperatures, humidities and times for conditioning and testing).
• Test specimens: Hose assemblies 400 mm long; at least three test pieces per test series.
• Conditioning: No test within 24 hours of manufacture; condition at standard temperature and humidity for at least 3 hours (per ISO 471).
• Apparatus:
  • Draught‑free room maintained at standard temperature.
  • Steel stands to support the hose horizontally.
  • Glass tube/fuel line to supply fuel, with fuel level set 900 mm above the test piece.
  • Fuel tray (350 mm × 350 mm, 40 mm sides).
  • Fuel: commercial heptane (distillation range ~80 °C to 110 °C).
  • Fuel tray charge: 0.5 dm³ water + 2 dm³ heptane.
• Procedure: Fill hose with heptane (no trapped air), place tray so flame impinges on hose, ignite heptane and record time to leakage. Leakage is indicated by increased flame intensity at the hose location. Tests are terminated on leakage or when tray fuel is consumed.
• Acceptance criterion: No leakage may occur earlier than Tmin after ignition; Tmin is specified in the applicable product standard (ISO 13774 itself defines the test method; the allowable Tmin is set elsewhere).
• Repeatability controls: If flame exposure is unstable or results vary excessively, additional specimens are required.
• Test report: Must include reference to ISO 13774, hose description, test conditions (room temperature, draught observations), individual and mean leakage times (or exposure time if no leakage), and test date.

Applications and users

This standard is practical for:

• Hose manufacturers and component suppliers validating fire performance of fuel hoses.
• Automotive OEMs and tier suppliers specifying safety and durability requirements.
• Independent test laboratories performing flammability testing and certification.
• Regulatory bodies and quality assurance teams assessing compliance of fuel-system components.

Keywords: ISO 13774:1998, flammability test, rubber hoses, plastics hoses, fuel hoses, heptane, internal‑combustion engines, hose testing.

Related standards

• ISO 471:1995 (conditioning for testing)
• ISO 8030:1995 (method of test for flammability of other types of rubber and plastics hoses)