Emissions from bio-based building products

The study focused on the emission behaviour of wood and the occurrence of corrosion on lead coupons due to these emissions when both materials were combined in a modified Oddytest (Oddy 1973, modified). Wood may not seem like a challenging environment for corrosion but by its porous micro- and ultrastructure wood has complex interactions with water that greatly affects its physical, mechanical, and chemical properties, including corrosion (Zelinka 2014). Wood can be considered as one of the major emission sources of formaldehyde and other volatile compounds. During the kiln drying of wood, the hydrolysis of cell wall components (cellulose, hemicellulose and lignin) leads to formation of furfural, formaldehyde and very volatile acids, e.g. acetic and formic acid. In addition, at a relative humidity of 20 % an initial molecular layer of water on the metal surface can react with atmospheric formaldehyde to produce formic acid which in turn causes metal corrosion (Hatchfield et al. 1986).