ISO 24638:2021

Overview

ISO 24638:2021 - Space systems: Pressure components and pressure system integration defines baseline requirements for the design, fabrication, testing, assembly, installation, inspection, operation and maintenance of pressure components and integrated pressure systems used in spacecraft and launch vehicles. It applies to components such as lines, fittings, valves, bellows, hoses and other non‑vessel pressure parts. The standard supports safe, reliable spaceflight pressure system performance and explicitly excludes pressure vessels/pressurized structures (see ISO 14623) and engine components.

Key topics and technical requirements

ISO 24638 covers a broad range of technical subjects relevant to space systems pressure components and pressure system integration, including:

• Design requirements: loads, pressure and environmental definition, strength, stiffness, thermal effects, stress and fatigue (safe‑life) analyses, and survivability against debris/meteoroid impacts.
• Materials and fabrication: metallic and non‑metallic material selection, processing, contamination control and cleanliness to meet spaceflight requirements.
• Quality & qualification: quality assurance programmes, inspection planning, QA techniques, acceptance testing and qualification test requirements for spaceflight hardware.
• Operation & maintenance: operating procedures, safe operating limits, inspection, repair/refurbishment, storage, reactivation and recertification of pressure components and systems.
• System‑level analysis and design: system pressure and functional analysis, system hazard analysis, routing, assembly, separation, shielding and grounding considerations for integrated pressure systems.
• Component selection & controls: criteria for connections, valves, regulators, pumps, fracture/leakage mitigation, oxygen‑system specifics, interlocks and safety critical control logic.
• Protection & pressure relief: relief device sizing, venting, automatic relief, isolation and negative‑pressure protection for spacecraft and launch vehicle pressure systems.
• Mechanical & electrical environments: acceleration, shock, vibration, torque loads, RF and hazardous-atmosphere considerations for electrically actuated components.

Applications and users

ISO 24638 is essential for organizations involved in the design, manufacture, integration and certification of spaceflight pressure systems, including:

• Aerospace system and mechanical engineers designing spacecraft and launch vehicle fluid systems
• Pressure component manufacturers and suppliers (hoses, fittings, valves, bellows)
• Systems integrators and avionics teams responsible for routing and assembly
• Quality assurance, test laboratories and certification authorities performing qualification and acceptance testing
• Operations, maintenance and ground‑support teams managing safe handling, storage and recertification

Use of ISO 24638 helps ensure consistent pressure system safety, minimizes leakage and failure risk, and supports regulatory compliance and mission reliability.

Related standards

• ISO 14623 - Requirements for pressure vessels and pressurized structures in space systems (complements ISO 24638)
• Other ISO and aerospace standards referenced in ISO 24638 provide normative testing and material specifications (see the standard’s normative references for details).