Specification

22 columbiaforestproducts.com Hardwood Plywood Grading Guide 2015
ANSI/HPVA HP-1-2009 STANDARDS©
The Hardwood Plywood and Veneer Association (HPVA) is an ANSI-accredited
standards developer that works through its participating membership and other
interested outside parties to develop a voluntary standard for hardwood and
decorative plywood under due process guidelines set forth by the American
National Standards Institute (ANSI). The resulting national consensus standard
bears the name, “American National Standard for Hardwood and Decorative
Plywood, ANSI/HPVA HP-1- Current Year,” often shortened to ANSI/HPVA HP-
1. Any other reference is not appropriate. It is often erroneously called the ANSI
Standard, but there are hundreds of ANSI standards, only one of which covers
our industry. ANSI does not write the standard or bear any responsibility for its
content. The sole involvement by ANSI is to provide a protocol for the develop-
ment of a standard that includes participation and sign-off by all interested par-
ties in the process, and a format to use so that the resulting standard conforms
to due process requirements to qualify for the ANSI designation.
The history of the standard is rich, beginning in 1931 as Commercial Standard
CS 35-31, evolving through the National Bureau of Standards as PS 51-71,
to its nal version today. As mentioned above, it is a voluntary consensus
standard, meaning compliance is voluntary, and the contents are a result of a
consensus of those involved in its development. While this may seem to be a
simple process, today’s version of the standard is the result of an arduous and
tumultuous process. It is intended to provide a baseline by which a panel or lot
of panels may be judged to ensure what is delivered is what is specied. Once
a panel provider agrees to or professes to conform to the standard, it becomes
mandatory.
It is important to understand that because of the natural differences in how
the look of wood will vary from piece to piece, even from the same tree, every
grade will include a range of appearance from the low end of the grade to the
high end. The tables in the ANSI/HPVA HP-1 standard and
abbreviated here for simplication purposes establish a minimum appearance
for each grade. In other words, the tables essentially say that if a given
attribute such as a small burl is present, it can’t exceed the size and quantity
restrictions listed in the table. What the tables do not say and should not be
interpreted to say is that for any grade, every face in that particular grade must
have every attribute listed in the amount and size listed in the applicable table.
The truth is that not every panel will have every characteristic. Some will have
virtually none, but others will have a combination of them, often making the nal
determination of the grade status of a given piece of veneer quite perplexing.
Sometimes a panel face with a faint characteristic that objectively is outside
the permitted size for a given grade will look much more desirable than another
that has several characteristics that are within the permitted limit, but which are
actually quite ugly, yet objectively meet the grade. The resulting inclination is
to select the better looking face and reject the ugly one. In fact, quoting from
the current industry standard, ANSI/HPVA HP-1-2009, Section 3.3.1, “NOTE:
Because of the inherent individuality of trees, consideration should be given to
the overall appearance of the veneer face to determine the appropriate grade
for that veneer.”
Regardless of the fact that every effort has been invested to ensure that the
standard is as objective as possible, there will always be some level of subjec-
tivity involved when making the nal decision as to the grade of a given sheet
of veneer. For this reason, there is almost always some degree of overlap in
appearance between the bottom end of one grade and the top end of the next
grade down, as illustrated in Diagram 1 below.
As can be seen in this diagram, as we go from one grade to the next, not only
does the variation in appearance get wider for each, but the amount of overlap
between the low end of one grade and the high end of the next grade down
gets wider as well.
While the standard consists of numerous sections and complete tables for
every grade of face and back by species category, it also includes sections
and tables relating to core requirements, glue performance, formaldehyde
emissions, dimensions and tolerances, and testing methodology. The follow-
ing tables are offered as a condensed version of the grade tables in the ANSI/
HPVA HP-1 standard for a few select species categories showing a small num-
ber of limiting criteria for illustration purposes only. Please check the current
ANSI/HPVA HP-1 standard for the full tables and narrative for more complete
information.
Note: Some exotic species such as Amaranth/Purpleheart (Peltogyne panicu-
lata) or Zebrano (Microberlinia brazzavillensis), or unusual matchings such
as diamond or sunburst do not t into the grading tables described here or in
the industry standard. These and even certain domestic woods such as bird’s
eye maple (Acer saccharum) or wormy chestnut (Castanea dentata) must be
carefully specied to include expected appearance. They will not be applicable
to any particular grade, and therefore should be considered as agreed upon be-
tween buyer and seller for appearance purposes. Even so, other requirements
of ANSI/HPVA HP-1, including dimensional tolerances, glue performance, and
formaldehyde emissions, among others, shall apply.
A
B
C
DIAGRAM 1
ANSI/HPVA HP-1-2009 © 2009 By the Hardwood Plywood and Veneer Association