During the production of plywood, formaldehyde-based adhesives are generally used, so the finished product will release free formaldehyde to varying degrees. When the free formaldehyde content exceeds a certain limit, it will affect human health. Testing the formaldehyde release of plywood is a complex process. The following method can be used to make a simple preliminary judgment on the formaldehyde release of plywood. First, pile unused plywood in a small room, close the doors and windows, and observe it after a period of time. If there is no pungent odor, it indicates that the formaldehyde release of the plywood is low and its use will not affect human health; if the odor is strong or there is a tearing sensation, it indicates that the formaldehyde release of the plywood may be high.
Regarding the formaldehyde issue of plywood, its internal pores have a pore size between 0.27 and 0.98 nanometers and are arranged in a crystalline pattern. It also possesses weak electrical properties. Formaldehyde, ammonia, benzene, toluene, and xylene molecules all have diameters between 0.4 and 0.62 nanometers and are polar molecules, giving it the characteristic of preferentially adsorbing harmful gases such as formaldehyde, benzene, and TVOCs, thus achieving the effect of purifying indoor air. It can adsorb and decompose formaldehyde, and can be reused after being exposed to sunlight.