Determination of the quantity of the formaldehyde release of plywood by different methods

This work discusses free formaldehyde (HCHO) emission and methods of determining the quantity of free formaldehyde from plywood of rotary peeled veneers. The plywood samples were laboratory manufactured from rotary peeled veneer of beech (Fagus sylvatica), poplar (Populus nigra) and black locust wood (Robinia pseudoacacia). Free formaldehyde was determined by perforation and diffusion WKI- 24 methods using both iodometric titration and spectrophotometric analysis (with acetylacetone as a reagent). The effect of various methods on determining free formaldehyde and the relation between various test results were analysed. The results of perforation and those of diffusion WKl-24 method show linear relation. Free formaldehyde emission from rotary peeled veneers is negligible. The perforation method with spectrophotometric analysis has proved to be the most precise.