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Three-layer polymeric diphenyl-methane-diisocyanate (pMDI)-bonded particleboards (PBs) were produced with different proportions of simulated recovered wood (rW) in the core layers (cLs) to assess the effect of rW on the formaldehyde (FA) release of PB. A pre-test was conducted on furniture and particle mixtures of rW to determine the range of expectable FA emission of rW. The FA content of the raw particle mixtures could be predicted from the contents of the individual raw material and did not change compared to the PB. FA content correlated strongly with PB-FA emission. It was possible to predict the maximum PB-FA contents, which should not be exceeded according to F**** and CARB 2 by linear regression models. At moderate and high total FA emission levels, the FA emission of the particle mixtures was approximately 60% higher than the emission of PB blocks. At low total FA level, the flask method and the gas analysis method exhibited different results with regard to the emissions from particles and their respective PBs.

A new and fast system for determining formaldehyde (HCHO) release of wood based panels (WBPs) for use in manufacturer's labs was developed. For sample preparation, solid phase microextraction (SPME) with a derivatisation step was used. The analytical system consists of a gas chromatographic column (GC) coupled to a high field asymmetric waveform ion mobility spectrometer (FAIMS). The emitted HCHO is determined in gaseous form, i.e. without trapping it in water. The system runs quasi-continuously with a cycle time of 20 min. This paper explains the basic functioning, and presents first results from a field trial.