Preface This is the second edition of CSA Z305.12, Safe storage, handling, and use of portable oxygen systems in residential buildings and health care facilities. It supersedes the previous edition, published in 1998 under the title Guide for the Safe Storage, Handling, and Use of Portable Oxygen Systems in Home, Domiciliary, and Healthcare Settings. Scope 1.1 This Standard applies to the safe storage, handling, and use of portable oxygen systems (which provide medical oxygen in high-pressure oxygen cylinders, liquid oxygen systems, and oxygen concentrators) in residential buildings and health care facilities. 1.2 This Standard includes requirements for maximum aggregate storage quantities of gaseous and liquid oxygen. 1.3 In CSA Standards, \"shall\" is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; \"should\" is used to express a recommendation or that which is advised but not required; \"may\" is used to express an option or that which is permissible within the limits of the standard; and \"can\" is used to express possibility or capability. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application. 1.4 The values given in SI (metric) units are the standard. The values given in parentheses are for information only.