Preface This is the fifth edition of CSA Z275.1, Hyperbaric facilities. It supersedes the previous editions published in 2005, 1993, 1982, and 1974. This Standard was prepared as a result of a formal review of industry requirements and takes into consideration current thinking and proven practices in the use of hyperbaric chambers for treatment as might be required in diving operations, work under compressed-air conditions, medical treatment, and research. It contains the requirements for the design, construction, maintenance, and testing of hyperbaric chambers. For the purpose of improved application to dive support and clinical settings, this edition has been extensively reorganized from the fourth edition. It has been technically updated to correspond with updates to related standards in the CSA Z275 series of standards as well as with ASME PVHO-1. Changes to this edition include the following: a) For purposes of international harmonization, the A, B, C classification for hyperbaric chambers has been replaced by descriptor categories ? single-occupancy, stationary multiple-occupancy, transportable DDC, evacuation, submersible compression, and chambers for tunneling a caisson work. b) Additional requirements for single-occupancy chambers have been added. c) Additional requirements for clinical applications have been added. d) Additional requirements for research applications have been added. e) Guidelines for selection, installation, maintenance, and cleaning of compressor/purification-type breathing air systems have been added. f) Sample collection for compressed breathing air analysis have been added. g) Recommended analytical procedures for the analysis of compressed breathing air have been added. h) Moisture content in compressed breathing air at typical user pressures have been added. CSA Group acknowledges that the development of this Standard was made possible, in part, by the financial support of the Canadian government departments responsible for occupational health and safety. In addition, financial support was received from the Diver Certification Board of Canada, the Canadian Association of Diving Contractors, and several commercial diving companies. Scope 1.1 General 1.1.1 This Standard applies to hyperbaric chambers that have as their primary function the subjection of humans to pressure environments exceeding 1 atmosphere absolute, such as those required in diving operations, work under compressed-air conditions, medical treatment, training, and research. 1.1.2 This Standard establishes minimum requirements for the operation, use, design, construction, maintenance, and testing of all hyperbaric chambers. 1.2 Classification of human occupancy hyperbaric chambers 1.2.1 General This Standard addresses the following classes of human-occupancy chambers: a) chambers used for clinical HBO treatment and/or for research purposes; b) chambers used for occupational diving operations; c) chambers used for tunneling and caisson operations; and d) hyperbaric chamber systems in support of offshore diving operations. 1.2.2 Chambers used for clinical HBO treatment and/or research purposes A clinical HBO chamber is a hyperbaric facility that is overseen by a trained safety director and a Level 2 or Level 3 hyperbaric physician, licensed in the jurisdiction in which they practice medicine, who adheres to the Standard of practice as set out by the Canadian Undersea and Hyperbaric Medical Association (CUHMA). Refer to Clause 17 for requirements applicable to research facilities used for human-subject research. 1.2.3 Types of hyperbaric chambers 1.2.3.1 Single-occupancy chamber A single-occupancy or mono-place chamber is a hyperbaric chamber normally intended for the treatment of one person and capable of oxygen or air pressurization to a depth not exceeding 20 msw (66 fsw) for the provision of hyperbaric oxygen therapy, normally for clinical applications only. 1.2.3.2 Stationary (multiple-occupancy chamber) A stationary chamber is a multiple-occupancy or multi-place hyperbaric chamber permanently installed in a vessel, platform, or shore-based facility and fixed to a permanent foundation, i.e., the vessel, platform, or building in which it is housed. 1.2.3.3 Transportable DDC (double-lock chambers) for occupational diving/caisson operations. A transportable deck decompression chamber (DDC) is a multiple-occupancy hyperbaric chamber with two locks (compartments) that can operate to transfer personnel in and out of the main lock while maintaining pressure of the main lock and that can be moved to a diving or caisson site to support onsite operations. This chamber may be temporarily set up as a stationary chamber during the period of a contract requiring hyperbaric support. Note: These chambers are used for emergency pressure related ailment and/or for surface decompression procedures. They conform to the requirements stated in Clause 5.2 of CSA Z275.2 and are designed to operate at pressures of 6 ATA or greater. 1.2.4 Evacuation An evacuation chamber is a single- or multiple-occupancy hyperbaric chamber that has as its primary function the emergency transportation under pressure of an individual at risk of, or suffering from, a pressure-related ailment. This chamber has a minimum pressure rating of 3 ATA. This sub-class also includes hyperbaric rescue craft (designed in accordance with IMCA D 053) and hyperbaric stretchers (see Clause 11.7). 1.2.5 Submersible compression chamber A submersible compression chamber (SCC) is a hyperbaric chamber that is capable of transporting personnel, at elevated pressures, from the surface to an underwater site and vice versa, and can be mated to a DDC for the purpose of transferring an individual under pressure while performing saturation diving. 1.2.6 Chambers used for tunneling and caisson operations These include transportable DDC chambers (see Clause 1.2.3) installed in the TBM and Evacuation chambers to transfer a worker to and from the TBM (see Clause 1.2.3). 1.3 Hazards This Standard covers special hazards associated with the design, construction, operation, and maintenance of hyperbaric facilities (See Annexes A, B, and C for a description of potential hazards). Consideration and control of these hazards is the basis for criteria in this Standard. 1.4 Terminology In this Standard, "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; and "may" is used to express an option or that which is permissible within the limits of the Standard. 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. 1.5 Units of measurement The values given in SI units are the units of record for the purposes of this Standard. The values given in parentheses are for information and comparison only. Note: See Annex D for conversion table.