Preface
This is the third edition of CSA Z275.3, Occupational safety code for work in compressed air environments. It supersedes the previous editions, published in 1986 and 1974 under the title Occupational Safety Code For Construction Work in Compressed Air.
This Standard is one of a series of CSA Standards on diving and caisson systems covering hyperbaric facilities, commercial diving, and construction work in a pressurized air environment.
Current requirements for work in a pressurized air environment vary from province to province (and territory to territory), particularly in the area of limiting working periods and controlling decompression procedures. The various methods also differ greatly from those in many other parts of the world. The
Technical Committee therefore decided to produce this Standard as a foundation for the development of uniform requirements governing the control of hazards associated with construction work in a pressurized air environment across Canada.
This Standard was prepared by the Subcommittee on Work in Compressed Air Environments, under the jurisdiction of the Technical Committee on Diving and Caisson Systems and the Strategic Steering Committee on Occupational Health and Safety, and has been formally approved by the Technical Committee.
Scope
1.1
This Standard applies to all work in compressed air environments at pressures above 20 kPa (3 psig) and sets forth requirements for the health and safety of workers exposed to these environments. Note: In addition to the requirements of this Standard for the protection of workers, requirements can be prescribed by the authority having jurisdiction.
1.2
This Standard applies to every shaft, tunnel, caisson, enclosure, and similar type of work site in which a worker is, or is likely to be, subjected to working in compressed air.
1.3
This Standard does not apply to divers or workers employed in diving bells (see CAN/CSA-Z275.2) and to hyperbaric treatment facilities (see CSA Z275.1).
1.4
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; 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
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. All air pressures specified in this Standard are expressed in kPa gauge (above atmospheric pressure) with the equivalent psi gauge units shown in parentheses.
