Depending on your location, check with the folks that have jurisdiction to find out what the relevant code is.
If applicable, the 2000 Uniform Plumbing Code has a chapter for Health Care Facilities and Medical Gas and Vacuum Systems.
Also, for comprehensive information, look at the Compressed Gas Association’s, “Handbook of Compressed Gasses.” This book is somewhat expensive but it is worth it if you will be involved in the design of facility that uses compressed gas. There are a lot of design considerations that are not obvious if the facility uses a cryogenic storage tanks and the Handbook will discuss most of the associated safety issues.