CGA hydrogen background

CGA G-5 Ninth Edition: Essential Hydrogen Storage and Safety Information

CGA would like to announce the release of CGA G-5: 2024, Hydrogen, 9th edition.  This publication provides information on the physical and chemical properties of hydrogen and proper handling and use. It is intended to provide background information for personnel involved in the manufacture, distribution, and use of hydrogen.

CGA G-5 provides important safety and operational information about hydrogen and serves as a reference for material in other CGA hydrogen publications.  CGA G-5 covers the following topics:

  • General properties, uses, and manufacturing techniques
  • Containers for storage and transportation
  • Cylinder storage
  • Cylinder handling
  • Gaseous hydrogen systems
  • Liquid hydrogen handling and use

The ninth edition includes the following updates:

  • Under manufacturing techniques, added steam reformation, partial oxidation, autothermal reforming, gasification, and water electrolysis.
  • Added details about fuel cell operation.
  • Added methods of gaseous hydrogen transportation and storage.
  • Added tube trailers and gaseous hydrogen receivers.
  • Added hydrogen pipelines.
  • Updated liquid hydrogen trailers and tanks.
  • Added metal hydrides and other storage methods.
  • Added a glossary of commonly-used terms for hydrogen and fuel cells.
  • Added an explanation of ullage in liquid hydrogen storage tanks.

CGA G-5 is going through the final stages of designation as an American National Standard (ANS) and will be identified as ANSI/CGA G-5.  An ANS must be approved by a broad-based consensus body consisting of members from organizations and people in addition to CGA members.  Only one ANS is allowed for a given subject matter, so this means that CGA owns the ANS for the material in ANSI/CGA G-5.