CGA G 5.6 : 2005(R2013)

1 Introduction
2 Scope and purpose
3 Definitions
4 Design philosophy
   4.1 General criteria
   4.2 Properties of hydrogen
   4.3 Metallic materials
   4.4 Compatibility with nonmetallic materials
   4.5 Piping systems
   4.6 Hazard analysis and risk assessment
   4.7 Site selection
5 Piping, valves, and equipment
   5.1 General criteria
   5.2 Material selection criteria
   5.3 Electrical hazardous area requirements
   5.4 Piping
   5.5 Valves
   5.6 Other equipment
6 Cleaning
   6.1 General requirements
   6.2 Postinstallation cleaning
7 Construction
   7.1 General criteria
   7.2 Specification and manufacture of line pipe material
   7.3 Construction plan
   7.4 Pipe fabrication and welding
   7.5 Assembly and installation
   7.6 Inspection and examination
   7.7 Nondestructive testing
   7.8 Documentation
8 Design and construction of stations
   8.1 Function
   8.2 Design brief
   8.3 Control station elements
   8.4 Standards and design codes
   8.5 Materials and fabrication
   8.6 Access limitation
   8.7 Location
   8.8 Grounding
   8.9 Installation
   8.10 Pressure and leak testing
   8.11 Commissioning
   8.12 Operation
   8.13 Filters/screens
9 Operation and monitoring
   9.1 Operation and maintenance manual
   9.2 Management systems
   9.3 General safety requirements
   9.4 Personnel for operation and maintenance
   9.5 Welding and cutting
   9.6 Shutdown, repair, and startup of pipelines
   9.7 Hot-tapping hydrogen pipelines
   9.8 Venting and pressure relief
   9.9 Commissioning pipelines and stations
   9.10 Operation and monitoring
   9.11 Information to third parties, work adjacent to
        pipelines, and update of documents
   9.12 Specialized surveys
   9.13 Damage to the pipeline system
10 General protective measures
   10.1 Emergency response plan
   10.2 Accident and damage report
   10.3 Safety management system
Appendices
Appendix A - Typical arrangements for pipelines systems
Appendix B - Embrittlement and environmental damage mechanisms
             involving hydrogen and applicable test
             methods (Informative)
Appendix C - Table of nominal alloy compositions and ranges
Appendix D - Metallurgical factors affecting hydrogen
             toughness and brittle fracture mechanisms (Informative)
Appendix E - Table of typical safety distances for hydrogen
             control and isolating/metering stations (Informative)
Appendix F - Example of preventive maintenance program for
             hydrogen pipelines (Informative)
Appendix G - Composition criteria for hydrogen and
             mixtures (Normative)
Appendix H - Requalification of existing pipelines for
             hydrogen service (Normative)
Appendix I - Ultra high purity hydrogen pipelines (Informative)
Appendix J - Examples of risk criteria applicable in The
             Netherlands and in the United Kingdom (Informative)
Appendix K - References (Informative)
Appendices figures

Provides a harmonized standard on metallic transmission and distribution piping systems carrying pure hydrogen and hydrogen mixtures.