| Numerous studies have shown that building products for indoor are the main source of volatile organic compounds and seriously impact on indoor air quality. The wood-based panel is a kind of very durable material, and it is widely used to produce furniture, wood product and building material.It was mainly studied in the paper that compounds and its concentrations of VOC were released from particleboards and overly particleboard and impacts of environmental factors on emissions of VOC were analyzed. The difference between particleboard and plywood in these properties was studied. It was concluded as following.1. On the basis of climate chamber, TVOC concentrations emitted from the particleboards with different hot-pressing parameters and thickness, overly particleboard and plywood were continually measured. It was found that the tendencies of different panels were consistent, that is, the concentration value rapidly raised to the peak and then it quickly decreased with the exposure time increasing till it reached some invariable value. The emission peak values of 7 panels which were commonly sold in Chinese markets ranged from 47μg/m3 to 120μg/m3, and the stable values from 24 to 38μg/m3.The lowest emissions were from overly particleboard, and the highest emissions from the 18mm particleboard. The emission peak values from two kinds of floors ranged from 35to 36μg/m3, and the stable values from 19 to 21μg/m3. They became stable earlier.2. It is showed that the main elements of VOC emitted were composed of aromatics, alkanes, aldehydes and terpenes by measuring the compositions and its concentrations of VOC emitted from particleboards and plywood, and they accounted for more than 90% of the total concentrations. Especially, the concentrations of VOCs which are indeed bad in human health were very high, such as toluene, ethyl benzene, xylene and etc. The compounds of halogenated hydrocarbons, ketones, ester and others were also determined in the VOCs emitted.3. By anglicizing compositions and their concentrations of VOCs and emission levels of TVOC emitted by 7 panels, it was showed that producing parameters affected VOC emissions. With the increasing of hot-pressing time and the thickness of panel, the emissions increased, and especially the raised rates of aromatics, terpenes and alkanes were obvious. The effect of overly on reducing VOC emissions was marked. It could decrease the types and concentrations of compounds, and especially enclosed aromatics having adverse effect on health. On the basis of above analysis, it was concluded that the VOC emissions were reduced by properly tempering the hot-pressing parameters. TVOC releasing of plywood compared with the particleboard owning the same thickness were lower, and even were lower than the one of other thinner particleboards. The types and concentrations of VOCs (main compositions were aromatics, terpenes from plywood) also were reduced.4. Envirenment temperature influenced the TVOC emission, compositions and their concentrations. With the increase of temperature, TVOC emissions, compositions and their concentrations also rise. With the test time prolonging, the concentrations of VOC did not only decreased, but the number of VOC types declined. TVOC emissions at every temperature were simulated according to the model of first-order attenuation. The relation between temperature and the coefficients of the model of first-order attenuation was built. By doing this was the relation between temperature and TVOC emission built. It was justified to match well with the experimental values.5. Environmental relative humidity also influenced the TVOC emissions. With the rising of relative humidity, the concentrations released by all kinds of panels were raised according to nonlinear relation. The emissions of formaldehyde in the different humidity were measured, too. It was found that impact of relative humidity on formaldehyde was more obvious than the one on VOC emissions. The reason may be that formaldehyde is soluble in water, while VOC is not.
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