ISO 19921:2005

Overview

ISO 19921:2005 - Ships and marine technology - Fire resistance of metallic pipe components with resilient and elastomeric seals - Test methods specifies reproducible test procedures to determine whether metallic valves, couplings and similar piping components that contain resilient or elastomeric seals retain their function and remain leak-tight after exposure to fire. The tests are performed on a test bench that meets the requirements of ISO 19922. The standard is used to demonstrate fire resistance for shipboard piping systems and to produce formal test certificates.

Key topics and technical requirements

• Scope: Metallic pipeline components (valves, couplings, fittings, expansion joints, filters) containing elastomeric seals used in ship engineering systems.
• Test pieces: Minimum of three test pieces of different sizes; stored at ambient temperature for 24 h prior to testing. Test pieces may be tested with (F) or without (B) fire sleeve/protection.
• Measured values: Water temperature (inlet/outlet), flame temperature, water flow rate, internal pressure and gas consumption - recorded at intervals ≤ 2 minutes.
• Temperatures:
  • Flowing water at inlet: 80 °C ± 2 °C
  • Flowing water at outlet: max 85 °C
  • Flame temperature at specimen center: 800 °C ± 50 °C
• Pressures:
  • Working (during flame): 500 kPa ± 20 kPa (5 bar ± 0.2 bar) (alternatives by agreement)
  • Proof (after flame at ambient temp): at least 1.5 × nominal/working pressure for 5 minutes
• Duration: 30 minutes flame exposure (designation example: Test ISO 19921 - 30 - 5 - 24 - F)
• Heat flux / fuel:
  • Pre-mix propane flame with fuel flow 5 kg/h → total heat release ~65 kW
  • Propane purity ≥ 95%; gas consumption measured to ± 3%
  • For pipes >152 mm, additional burner rows to maintain heat flux (target 113.6 kW/m ± 10% at specified height)
• Preparation and procedure: Rinse test piece with water for at least 1 minute before test to evacuate air. Installation requires flame to completely enclose the specimen.
• Acceptance criteria: Component must remain tight during the fire test and pass the post-fire proof pressure. For non-flammable services, leakage ≤ 0.2 L/min may be acceptable.

Applications and users

ISO 19921:2005 is used by:

• Marine component manufacturers (valves, couplings, fittings) seeking fire-test qualification
• Shipyards and naval architects specifying fire-resistant piping systems
• Classification societies and certification bodies issuing test certificates
• Third‑party test laboratories operating ISO 19922-compliant test benches
• Procurement and safety engineers specifying compliance for shipboard systems

Practical uses include product qualification, compliance documentation, design verification, and procurement specifications for ship and offshore piping.

Related standards

• ISO 19922 - Requirements for the test bench used together with ISO 19921
• ISO 15837 - Gasketed mechanical couplings (referenced for coupling designs)

Keywords: ISO 19921:2005, fire resistance, metallic pipe components, elastomeric seals, ship engineering, test methods, ISO 19922, proof pressure, flame temperature.