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The effect of thermal modification and extracts of Scots pine sapwood and heartwood, and Norway spruce on the colonisation by the bacterium, Escherichia coli was studied. All wood samples caused more rapid decrease of bacterial numbers compared to glass, which was used as reference material. Pine sapwood caused somewhat faster decrease of bacterial count than the other wood types. On the other hand, both thermal modification and extraction increased the bacterial count on all the samples compared to untreated wood samples. Neither the amount of extractives nor the faster drying of the surface, to which the bacterial inoculum was added, could alone explain this result; rather it is likely that this is due to a combination of both factors.

The accuracy and precision of moisture content (MC) and specific gravity (SG) measurements were tested on two industrial on-line measurement devices using microwave technology: the Metriguard DME 2800 and the Mecano MVA. Both devices were installed in a laboratory measurement line, and to obtain accuracy and precision of measurements, in total 137 spruce veneer sheets and 51 birch veneer sheets were tested. Before measurement, the spruce veneer sheets were conditioned to four different nominal MC classes between 4 and 16 % and birch veneers to three classes between 4 and 10 %. The veneer sheets were passed through the measurement devices three times. After measurement, the MC and SG of each veneer sheet were assessed gravimetrically. Using microwave technology the MC and SG of spruce and birch veneers can be measured with good accuracy and precision. The root mean square error (RMSE) for MC measurements of the spruce veneer sheets was 0.2 % on both devices and for birch veneers it was 0.7 % for DME and 0.5 % for MVA. The RMSE for the spruce SG measurement was 0.008 for both devices and for birch veneers it was 0.013 for the DME and 0.022 for the MVA.

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This paper introduces a new type of contact drying method that has been developed at Aalto University in Finland. The paper also presents experimental results from tests with the new drying method. The drying system consists of a hot upper plate, a cold bottom plate, a vacuum inside the drying chamber and a mechanical press. An experimental drying device was built and used in a study to compare the new method with the currently used drying methods. The study includes drying time experiments and tests on veneer quality. The results were compared to veneers which had been dried in a convective dryer. Compared to conventional convective drying, the new method decreased the total drying time significantly, by approximately 50%. The preliminary tests show that the quality of the veneer was not compromised in the drying process. The new method could be used in the plywood and LVL manufacturing process, as well as in special drying applications. The results showed that the new system was a viable drying method and there is potential for improvements in the veneer manufacturing process.