One、What are the grades of plywood?
Plywood is classified into three grades: top-grade, first-grade, and acceptable based on the material and processing quality of the panels. Some companies also use designations such as A-grade, double A-grade, and triple A-grade for plywood, but these are not standard classifications and are no longer permitted on the market.
Two. How are the environmental grades of plywood classified?
Particleboard is a type of engineered wood, therefore its environmental rating should comply with relevant regulations for engineered wood. According to the standard GB/T 39600-2021 for formaldehyde emission levels of engineered wood and its products, formaldehyde emission levels are divided into three grades based on the specified limits.
Class E1 (≤0.124 mg/m³)
E0 grade (≤0.050mg/m³)
ENF grade (≤0.025mg/m³)
The standard for formaldehyde emission from engineered wood products specifies the emission level for a single product. However, in home renovation, not only engineered wood products but also some textile materials may release formaldehyde.
The indoor air quality standard (GB/T 18883-2002) implemented on March 1, 2003, is established to protect human health and prevent and control indoor air pollution. Specifically, the standard sets the limit for formaldehyde at a 1-hour average value of no more than 0.10 mg/m³.