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The aim of this study was to determine the concentrations of volatile organic compounds found in the air in five production halls at a furniture manufacturing plant. Tests were performed in production halls, where machining operations were performed both on wood and wood-based materials, in shop halls in which surface-finishing operations were performed, as well as a finished goods warehouse.A Tenax TA synthetic sorbent was used to adsorb compounds found in the air.Volatile substances were analysed by gas chromatography combined with mass spectrometry and thermal desorption. It was found that the microclimate in the examined production halls varied. Differences were observed not only in the type of compounds detected in the shop halls, but also in their amounts. The analysed air contained a broad spectrum of volatile compounds, mainly alcohols, glycols, aromatic hydrocarbons, aldehydes, esters and terpenes. The total concentrationof volatile organic compounds (TVOC) found in the air in the examined production halls varied within a very broad range from 795 to 5113 μg/m3. The concentrations of volatile organic compounds identified in the production halls were markedly lower than those specified by Polish legal regulations - the Ordinance of the Minister of Labour and Social Policy of 2002 (with later amendments).
This paper presents the results of investigations on the emission of volatile organic compounds (VOC) from oak wood surfaces finished with acrylic waterborne lacquers. The lacquers selected for the experiments were characterised by a different content of solids, fluctuating between 32 and 38%. The volatile organic compounds were analysed using a gas chromatography technique combined with mass spectrometry and thermal desorption (GC/MS/TD). Tenax TA was employed as an adsorption medium. The obtained results indicate that volatile organic compound emissions from the experimental waterborne lacquers varied widely from 388 to 1794 μg/m3. The most important constituents of emissions included compounds that belonged mainly to glycol ethers as well as aliphatic and aromatic hydrocarbons.
The objective of this research project was to determine, using the Life Cycle Assessment (LCA) techniques, the extent and character of consequences which can occur in the entire ecosystem in the result of production of unedged oak timber and selected wood-based materials. In order to estimate the environmental consequence of selected raw materials, the authors employed the LCIA procedure (Eco-indicator '99) based on the results of work of a team of experts from the Netherlands. The applied procedure allowed determining the influence of the resultant environmental effects on various important environmental aspects.
The paper presents results of investigations on the emission levels of volatile organic compounds from surfaces of furniture elements, both in the course of finishing processes and during ordinary utilization of finished products. Experiments were carried out on articles manufactured from particleboards finished with natural oak veneer and treated with nitrocellulose wood stain, nitrocellulose primer and acrylic finishing lacquer. Qualitative and quantitative analyses of the composition of volatile emissions were conducted with the assistance of gas chromatography combined with mass spectrometry.
Comparative studies of ipe (Tabebuia spp.) wood photodegradation cause by treatment with outdoor and indoor UV-A light irradiation. A study on photodegradation of ipe (Tabebuia spp.) wood by UV A light has been carried out. Two types of lamps were used in the tests, i.e. a UVA-340 lamp with a wavelength of 290 - 400 nm, emitting light resembling natural light, an a UVA-351 lamp with a wavelength of 300 - 400 nm, imitating light found indoors penetrating through window panes. Colour of the samples was measured using a Datacolour 600 spectrophotometer prior and after 1,5, 10, 25, 50 and 100-hour irradiation. Characterization of investigated material included determination of its chemical components. Despite the fact that ipe wood contains high concentrations of components playing an important role in the photodegradation process (e.g. 37.2% lignin) the detected changes are minor and do not exceed 1 point. The change in colour (∆E) for ipe wood surface was mainly caused by changes in the chromatic coordinate (b*) and the lightness coordinate (L*). Greater changes occurred under the influence of a UV-340 lamp emitting the type of light resembling that found outdoors.
In this work the optimum resination rate of white mustard straw particles with UF resin in the production of straw particleboards was investigated. The resination rates used in this study were 10, 12 and 14%. For the selected resination rate, the possibility of reducing the density of the straw particleboards was also determined. In order to evaluate the hygienic parameters of the experimental boards, the formaldehyde content and volatile organic compounds (VOC) were determined. Moreover, using a thermogravimetric analysis (TGA) the boards’ disposal options by means of burning or co-incineration were investigated. The study results showed thata 10% resination rate enabled the production of white mustard particleboards of type P1 and P2, while the simultaneous reduction in their density to 600 kg/m3limited their application to dry conditions only, i.e. boards of P1 type. Thermogravimetric analysis revealed a variable thermal performance of the studied boards.The pine particleboards showed a higher thermal resistance, however, up to a temperature of 750°C, the samples of the experimental boards underwent a similar process of thermal destruction.
Comparative studies of ipe (Tabebuia spp.) wood photodegradation caused by treatment with acid and alkaline buffers. A study on photodegradation of ipe wood using xenon lamp and UV lamp light has been carried out. Colour of the samples was measured using a Datacolour 600 spectrophotometer prior to their soaking in acid and alkaline buffers, after soaking and successively after 1, 5, 10, 25, 50 and 100-hour irradiation. It was concluded that the treatment with acid and alkaline buffers causes opposite changes of the investigated colour coordinates. Samples after treatment with the acid buffer were lighter and yellower in colour, but less red, while after treatment with the alkaline buffer they were darker and redder, bur less yellow. Generally treatment with the alkaline buffer caused more significant changes of ipe wood in comparison to treatment with the acid buffer. Samples treated with the acid buffer were more prone to changes of colour (∆E*) due to light irradiation in comparison to the samples treated with the alkaline buffer. More significant changes of colour were observed in the case of UV irradiation in comparison to irradiation cause by xenon lamp light.
The paper presents the results of chamber tests conducted on UV-cured water-based lacquer coatings applied on different wood species. Volatile organic compounds were transferred onto Tenax TA and then they were assayed by gas chromatographycoupled with mass spectrometry and thermal desorption. It was found thatUV-cured water-based coatings may be potential sources of the emission of volatile substances and thus pollute indoor air. Concentrations of these compounds in the chamber depended on the type of the lacquer system used and the type of finished surface. The highest emission of volatile substances was recorded from coatings applied onto the surface of pine wood. The coatings tested released aldehydes, ketones and alcohols, while in the case of pine wood, terpenes were also emitted. Analyses conducted 24 h and 72 h after the samples had been placed in the chamber, showed that the amounts of compounds released varied over time.
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