B51-09

A safety bulletin exists for this standard. Click here to receive a copy. Preface  This is the seventeenth edition of CSA B51, Boiler, pressure vessel, and pressure piping code. It supersedes the previous editions published in 2003, 1997, 1995, 1991, 1986, 1981, 1975, 1972, 1969, 1965, 1960, 1957, 1955, 1951, 1945, and 1939. Scope 1.1 Except as indicated in Clause 1.2, Part 1 of this Standard applies to all boilers, pressure vessels, pressure piping, and fittings, as provided for by the Act (as defined in Clause 3) and identified in Part 1 of this Standard. Notes: (1) It is possible that the size limitations specified in provincial or territorial statutes or regulations will differ from those specified in Part 1 of this Standard. The applicable regulatory authority should be consulted. (2) The pressures specified in Part 1 of this Standard are gauge pressures above atmospheric pressure. (3) This Standard applies to all boilers, pressure vessels, pressure piping, and fittings installed subsequent to its adoption. 1.2 Requirements for compressed natural gas cylinders and refuelling station pressure piping systems and containers are covered in Parts 2 and 3 of this Standard. 1.3 This Standard does not apply to (a) pressure-retaining components in hydraulic elevators; (b) pressure-containment devices for gas-filled switchgear and controlgear; and (c) pressure vessels for the transportation of dangerous goods regulated by Transport Canada. 1.4 Where a clause in Part 1 of this Standard is at variance with a Code or Standard referenced in Part 1 of this Standard, the requirements of Part 1 of this Standard govern. 1.5 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. 1.6 The values given in SI (metric) units are the standard. The values given in parentheses are for information only. Nominal pipe sizes are expressed in non-dimensional terms.