ISO 15615:2022

Overview

ISO 15615:2022 specifies safety requirements for high‑pressure devices used on the high‑pressure side of acetylene manifold systems for welding, cutting and allied processes (up to 2.5 MPa / 25 bar). The standard applies to devices such as non‑return valves, automatic shut‑off devices, three‑way valves, stop valves, pressure gauges and multifunctional safety devices. It does not cover high‑pressure piping, flexible hoses or pressure regulators.

This third edition updates test and design requirements (e.g., added pressure‑gauge requirements, clarified three‑way valve tests, removed obsolete manual/remote shut‑off valve types) and emphasizes safe design against acetylene decomposition and overpressure.

Key topics and technical requirements

• Scope & definitions: Devices located on the high‑pressure side of acetylene manifold systems as defined in ISO 14114. Key device types and terms (non‑return valve, automatic quick‑acting shut‑off device, change‑over unit) are defined.
• Design: Metal parts in contact with gas must be electrically continuous and designed to remain at the same electrostatic potential as the device body to prevent static discharges.
• Materials: Materials shall comply with ISO 9539.
• Leakage limits
  • External: Tested per ISO 9090 (before and after type tests).
  • Internal: Maximum internal leakage ≤ 50 cm³/h for connections with internal bore <11 mm, or ≤ 0.41 × d (cm³/h) for larger bores (d in mm). After acetylene decomposition testing internal leakage ≤ 50 L/h.
• Pressure resistance: Device housings shall withstand 31.5 MPa (315 bar) for 5 minutes with no leakage or permanent deformation.
• Acetylene decomposition: Devices are subject to decomposition testing at an initial pressure of 2.5 MPa; no visible permanent deformation, no gas escape, no part ejection (internal damage permitted).
• Type testing: Comprehensive tests in Clause 6 include external/internal leakage, pressure resistance, acetylene decomposition, non‑return valve reverse‑flow and fatigue tests, endurance and trip‑pressure tests for relevant devices. Tests referenced to normal conditions (≈1.013 bar, 23 °C).

Practical applications and users

ISO 15615:2022 is intended for:

• Manufacturers of acetylene manifold components and multifunctional safety devices designing products for oxygen‑acetylene and similar systems.
• Test laboratories and conformity assessment bodies performing type testing and certification.
• Safety engineers, maintenance technicians and plant managers specifying, installing or servicing acetylene manifold systems.
• Procurement and compliance teams ensuring purchased equipment meets recognized safety standards.

Benefits include improved safety against acetylene decomposition incidents, standardized testing and clear leakage/pressure criteria to reduce operational risks.

Related standards

• ISO 14114 (acetylene manifold systems definition)
• ISO 9539 (materials)
• ISO 9090 (gas tightness)
• ISO 5171 (pressure gauges)
• ISO 15296 (vocabulary)
• ISO 10297 (cylinder valves)

Keywords: ISO 15615:2022, acetylene manifold systems, gas welding equipment, high‑pressure devices, acetylene decomposition test, pressure resistance test, internal gas leakage, safety requirements.