APA Plywood in Lowest Formaldehyde Release Class
All trees and wood products emit small amounts of formaldehyde. An oak tree, for example, emits 0.009 parts per million (ppm) of formaldehyde. See Formaldehyde and Engineered Wood Products.
The adhesive used to manufacture US trademarked plywood is phenol formaldehyde (phenolic) which does not release significant amounts of formaldehyde. Current scientific data indicates that the maximum formaldehyde level associated with phenolic bonded wood panel products is about the same as background levels present in outdoor air in an urban environment.
The UK Designated Standard and the Harmonised European Standard for wood-based panels, EN 13986 says that ‘wood-based panels glued with resins emitting either no formaldehyde or negligible amounts of formaldehyde after production as e.g. isocyanate or phenolic glue’ should be classified as E1 (the lowest formaldehyde release class) without needing further testing.
Formaldehyde levels in APA panels conforming to US PS 1 and PS 2 standards already meet the E1 requirements. Independent tests confirm that formaldehyde emission levels rapidly approach zero as finished US trademarked plywood panels age.
Japanese regulation for formaldehyde emissions from wood panels is widely considered the most stringent in the world. Their JAS standards for plywood and Structural Panels (OSB) do not directly specify a limit for formaldehyde emissions.
However, panels meeting the F**** standard for formaldehyde emissions (the most stringent requirement level) are required to have an average emission level below 0.30mg/l as tested to Japanese Standard JIS A 1460. APA PS 1 and PS 2 panels easily meet F**** requirements.
measures on formaldehyde release
APA member products are exempt from the Airborne Toxic Control Measure to Reduce Formaldehyde Emissions from Composite Wood Products. Section 93210 (c) (8) of the measure specifically states that composite wood products do NOT include:
- Structural plywood as specified in the Voluntary Product Standard – Structural Plywood (PS 1-19)
- Structural panels as specified in the Voluntary Product Standard – Performance Standard for Wood-Based Structural-Use Panels (PS 2-10 – sometimes designed by APA on its panels by APA’s own Performance-Rated Panel Standard – PRP 108)
- Structural composite lumber (LVL) specified in Standard Specification for Evaluation of Structural Composite Lumber products (ASTM D 5456-06)
- Oriented strand board
- Prefabricated wood I-joists as specified in Standard Specification for Establishing and Monitoring Structural Capacities of prefabricated Wood I-Joists (ASTM D 5055-05)
The CARB regulation was used as the basis for the Federal (US National) Regulation that comes into effect in 2013, therefore, the same exemption exists for the Federal (US National) formaldehyde provisions.
Phenolic glue is manufactured from resins consisting of phenol formaldehyde polymers by reacting together measured amounts of phenol and formaldehyde under carefully controlled conditions. These polymers consist of ‘chains’ of phenol and formaldehyde which are chemically linked together to form polymer molecules. These molecules possess physical and chemical properties which are completely distinct from the properties of either phenol or formaldehyde i.e. these polymers are new chemical entities and not simply mixtures of phenol and formaldehyde.
Once formed, the phenolic polymers are extremely stable and do not break down into their original phenol and formaldehyde molecules. It is this stability which prevents the release of formaldehyde from panels containing this type of water proof adhesive.
Confusion over the different types of formaldehyde adhesive in use has led to concern over the possible release of formaldehyde from wood products and the possible effect on health. Formaldehyde-related problems have been associated with urea formaldehyde adhesives, commonly used in the manufacture of interior plywood.