This publication, originally issued in 2015 has been revised to include customer station bulk storage systems.
The use of incompatible materials, unsuitable lubricants, improper cleaning and/or ingress of impurities and procedural failures have been identified as root causes of a number of severe incidents that have occurred over the past few years.
These incidents have involved liquid oxygen valves operating in concentrations greater than 90 mol %. These incidents have shown the need for continual improvement in the fundamental knowledge of the design, material selection, manufacturing, cleaning, installation, operation and maintenance processes related to valves in liquid oxygen service. It is essential that this information is communicated to liquid oxygen valve specifiers, suppliers and manufacturers as well as those who clean, assemble, install, operate and maintain these valves.
This publication covers isolation valves, control valves, check valves, pressure relief valves, drain, and vent valves in air separation units (ASUs), their backup and storage piping system, and customer station bulk storage tank systems. It addresses the design, material selection, manufacturing, cleaning, installation, operation and maintenance of oxygen service valves operating at temperatures below -30°C.
Valves in warm service connecting instrumentation devices are excluded from the scope of this publication. Although this publication is intended for ASUs, some of the principles may be applied to other cold oxygen installations.
The information contained in this publication only applies to new installations designed after the publication of this document and not to existing installations. However, the information contained in this publication may benefit existing installations or those in the project phase.
Furthermore, to the extent that they exist, national laws may supersede the practices included in this publication. It should be noted, that all local regulations, tests, safety procedures, or methods are not included in this publication and that abnormal or unusual circumstances could warrant additional requirements.
This publication is intended for those who are involved in the design, specification, procurement, installation, operation and maintenance of valves used in liquid oxygen and cold oxygen in air separation units and customer station bulk storage tank systems and similar applications.
The publication is part of the programme to develop Globally Harmonised publications amongst Regional Gas Associations.