The O437 Series is a series of Standards devoted specifically to
the wood-based mat-formed structural use panels commonly known as
OSB and waferboard.
CSA Standard O437.0 establishes property requirements for three
grades of OSB and waferboard currently commercially available,
namely: R-1, O-1, and O-2. The grade designations are intended
solely for identification purposes and do not imply ranking. Grade
property requirements are expressed as minimum or maximum averages
(five samples) with limits placed on minimum or maximum values
(single samples) and parallels the procedure for specifying
requirements in the US (see ANSI Standard A208.1, Wood
The O-1 and O-2 grades pertain to panels manufactured with
layers of oriented standards or wafers.
The O437 Series of Standards on OSB and Waferboard are written
in conformance the published Guidelines of the Canadian Standards
Association. Among other functions, Guideline L, The
Publication of CSA Standards, sets forth CSA policy covering
format, editorial style, and language of CSA Standards.
For the benefit of users of this series of Standards, the
following conventions, summarized from Guideline L, are applicable
when interpreting the requirements of these Standards:
(a) All numbered sections of the text are referred to as
Clauses. Within a Clause, identified and listed requirements are
referred to as Items.
(b) Mandatory requirements are those which it is essential to
satisfy, and they are stated using the verbal auxiliary
(c) The verbal auxiliary "may" is permitted in optional
(d) Notes which appear below clauses are intended to be
explanatory or informational and must not include mandatory
language. They are presented in italic typeface.
(e) Notes which appear below Tables and Figures are considered
part of the requirements of the Table or Figure. These Notes,
therefore, are written in mandatory language, but also appear in
(f) Appendices to a Standard are considered informational and
not part of the requirements of the Standard. However, Appendices
may be written in mandatory language so that users of the Standard
may invoke the content of an Appendix as requirements supplementary
to the basic Standard.