Publication Spotlight: CGA G-4.1, Cleaning of Equipment for Oxygen Service

Oxygen supports and accelerates combustion of most materials used in oxygen systems so it is essential that oxygen equipment and systems including all components and parts thereof are adequately cleaned to remove harmful contamination before the introduction of oxygen and to avoid ignition of components or systems.

CGA G-4.1, Cleaning of Equipment for Oxygen Service, is a harmonized publication that describes the cleaning methods and requirements for equipment used in the production, storage, distribution, and use of liquid and gaseous oxygen in order to reduce the risk of fire, explosion, or promotion of combustion.  These cleaning methods include:

  • mechanical cleaning (blast cleaning, wire brushing, tumbling);
  • aqueous cleaning (steam or hot water cleaning, alkaline cleaning, acid cleaning, detergent cleaning);
  • solvent cleaning (immersion cleaning, forced circulation, vapor degreasing); and
  • semi-aqueous/emulsion cleaning.

CGA G-4.1 also addresses the following:

  • planning requirements;
  • cleaning precautions;
  • environmental considerations;
  • cleaning equipment;
  • removal of cleaning agents;
  • rinsing and drying;
  • inspection after completion of cleaning;
  • acceptable contamination levels and contaminant detection thresholds for nonvolatile contaminants;
  • packaging and maintaining cleanliness;
  • labeling;
  • quality assurance, quality control measures; and
  • personnel safety and training.

CGA G-4.1 also provides information on the purpose and elements of a cleaning procedure as well as informative examples of cleaning procedures for various cleaning methods.