G-4.14: Design, Manufacture, Installation, Operation and Maintenance of Valves Use in Liquid Oxygen and Cold Gaseous Oxygen Systems

Several severe incidents involving liquid oxygen valves with concentrations above 90 mol% oxygen have been traced to critical issues such as the use of incompatible materials, unsuitable lubricants, improper cleaning, ingress of impurities, and procedural failures. These incidents highlight the ongoing need for improvement in the fundamental knowledge of valve design, material selection, manufacturing, cleaning, installation, operation, maintenance, and storage processes for liquid oxygen service.

To address these concerns, CGA, AIGA, EIGA, and JIMGA have collaborated to create this harmonized publication, covering isolation, control, check, pressure relief, drain, and vent valves used in air separation units (ASUs), backup and storage piping systems, and customer station bulk storage tank systems. The publication provides comprehensive guidelines on the design, material selection, manufacturing, cleaning, installation, operation, and maintenance of oxygen service valves operating at temperatures below –22 °F (–30 °C).

Now in its 3rd edition, this updated edition of G-4.14 includes key revisions that reflect the latest industry practices and expert knowledge.

Notable updates include:

  • New technical definitions;
  • The role of light hydrocarbons as a contamination source in the kindling chain;
  • Compatibility of lubricant or locking compound autoignition temperature (AIT);
  • Clarification on the differential pressure operation of isolation and throttling valves;
  • Guidelines for the installation of gas valves occasionally exposed to liquid;
  • Best practices for sourcing spare parts, valve repair, and complete valve assemblies;
  • Enhanced verification and validation procedures;
  • Improved material control and traceability.

Additional updates further enhance the scope and depth of this comprehensive resource.