Preface This is the fourth edition of CSA O153, Poplar plywood. It supersedes the previous editions published in 1980, 1976, and 1963. Changes in the fourth edition include the following: a) format changes for consistency with other recent CSA plywood standards; b) increased detail for panel and veneer grade requirements; c) increased emphasis and clarity on performance requirements for utilized adhesives, including removal of Interior Bond; d) requirement for in-plant production and quality control procedures, including auditing by a recognized third-party agency; e) increased detail for some test procedures; f) updated requirements for marking; and g) revisions to informative annex related to shipment re-inspection. Scope 1.1 This Standard applies to exterior bond, all-veneer plywood with a minimum of three plies and parallel grain direction of the face and back plies. 1.2 This Standard specifies requirements for a) a quality system; b) materials; c) panel construction; d) bonding; e) veneer and panel grades; f) dimensions and tolerances; g) marking; and h) testing. 1.3 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; "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.