What is F4 plywood (F Four-star Plywood) ?
F4 means F☆☆☆☆ or F 4-star or F Four-star, which is the top Formaldehyde Emission grade for plywood, fiberboard, MDF, OSB, HDF, wood furniture and other wooden products according to Japanese standard JIS A 1460 (2005) Building Boards Determination of formaldehyde emission – Desicator method .
JIS A 1460 (2005) is a part of JAS (Japanese Agricultural Standard) which is published by Ministry of Agriculture, Forestry and Fisheries (MAFF Japan) .
JIS A 1460 (2005) sets four grades for Formaldehyde Emission value . F☆☆☆☆ is the highest Formaldehyde Emission grade according to JIS A 1460 (2005) . F4 plywood means the plywood can meet the F☆☆☆☆ grades of Formaldehyde Emission according to JIS A 1460 (2005) . F4 plywood is the lowest Formaldehyde Emission plywood which can be used interior without limitation .
JAS Formaldehyde Emission grades: Grades (Rating) Average Value Max. Value F☆☆☆☆ 0.3mg/L 0.4mg/L
F☆☆☆ 0.5mg/L 0.7mg/L
F☆☆ 1.5mg/L 2.1mg/L
F☆ 5.0mg/L 7.0mg/L
Note: These values are achieved through Desiccator Test .
