Evaluation of formaldehyde emissions from composite wood products

With respect to the effects of undesirable formaldehyde exposure to human health and to the environment, emission level of this gas from wood composite product was measured in order to introduce a practical method for evaluating the amount of its emission from glued wood products. In this regard, particleboards panels were prepared from Haloxylon persicum using particles with three different moisture gradients using urea-formaldehyde adhesive. Formaldehyde emissions were evaluated using desiccators’ method according to ASTM D 5582-00.The results showed that the emission declines as the moisture gradient increases. The emission values were determined as 8.946 ppm, 6.312 ppm and 4.172 ppm for the particleboards with moisture gradients of 0, 2 and 4 percent, respectively. Increasing moisture gradient from 0 to 2 percent resulted in 29 percent and increasing moisture gradient from 2 to 4 percent resulted in 34 percent lower formaldehyde emissions, respectively. In addition, comparing the measured values with standard values showed that these particleboards should be only used in outdoor application rather than indoors.