Product characteristics of plywoodOSB and OSB as graded according to US Dept of Commerce NIST PS 1-95 and PS 2-92 and extended to include certain proprietary standards for plywoodOSB siding products Plywood species and species group designation as commonly used by producers for the North American market Number of layers of veneer in panel, including faces Exposure class as defined by NIST standards and indicated in grade stamp. North American structural panel grading agencies Manner in which panel is identified by a numeric or text code. Shape of panel edge on long dimension Grades as defined by NIST standards and proprietary siding grades Span Rating according to NIST standards and indicated on grade stamp As defined in the NIST standard, an additional classification of panel strengt Further specifications of the product not defined by standard Manner in which face(s) are finished