| In recent years, indoor air pollution has become one of major issues of common concern to the society. Volatile organic compounds (VOC) of indoor air have negative effect on human health. Wood-based panels are main source of indoor VOC. Therefore, the research of VOC evaluation released from wood-based panel would play an important role in improving indoor air quality of living environment.The aim of this research is to improve the indoor air quality, to reduce environmental pollution, and to protect human health. the assessment of impact factor of VOC released from commercial wood-based panel in decoration market is studied in this paper,.On the basis of processing, the influences of VOC released from different hot-pressing technology and surface finishing were analyzed, and the controlled methods of decreasing or slowing down the VOC release were investigated. The theoretical basis of cleaner production for wood-based panel was provided.In this paper, the VOC emissions released from different processing conditions were evaluated with the selected method, then the measures of cleaner production were carried out successively. The results are listed as followed:(1) By comparing and analyzing the evaluation methods and the impact factor of VOC emissions from wood-based panel show that comprehensive index method can evaluate VOC emissions from wood-based panel and conclude rating. This method has the advantages that are consideration to the maximum pollution, simple calculation and good practicality.(2) The evaluation of VOC emissions from different moisture contents and resin contents for 28 days showed that the comprehensive index and VOC release trend were consistent. Quantitative analysis the component of particleboards with different processing was detected at the 60th days after manufacturing. VOC emission values and pollution levels increased with moisture content, density, thickness, resin content and hot-pressing time. Aromatics released in a highest ratio. The VOC emission from single-layer structure particleboards were small than three layer structure particleboards and belongs to the light pollution level.(3) By comparing the total costs of different processing conditions with VOC emission values and comprehensive pollution index, the optimal processing conditions were concluded: moisture content of 12%, thickness of 0.6g/cm3, density of 8mm, resin content of 8%, hot-pressing time of 4min.The principal component analysis was adopted to analyze the VOC released from particleboards under different hot-pressing parameters. The main factors affect the properties were:TVOC concentrations, aldehyde ketone, esters and aromatic hydrocarbons. According to the evaluation of particleboards, the worst quality of particleboards was pressed as the thickness 22mm.Three layer structure particleboards were in the second of the relatively heavy pollution.(4) VOC emissions of particleboards, which were coated with water through the varnish, alkyd varnish and nitrocellulose lacquer alkyd varnishes, was detected and evaluated. with the extension of exposure time, The VOC emissions of the particleboards has a downward trendafter finished. The comprehensive index pollution levels of three kinds of paints have the similar trendance with the VOC emission values. The VOC level was serious at the first three days, and then the VOC emissions decreased to the moderate level at the fifth day, at last it turned into the clean level after seven day.(5) Based on results of VOC emissions of particleboards under different processing parameters, the requirement of cleaner production was proposed:the moisture content of single-layer structure particleboards were no more than 14%; thickness should not exceed 22mm; resin content was no more than 10% and the hot-pressing time should no more than 6min were better for processing. The surface finishing is an effective control method for terpenes and aldehyde ketone emissions from the wooden base materials.
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