Activities of moulds on wood as a function of relative humidity during desorption and absorption processes
Yujing Li, L Wadsö
Three different types of indoor moulds: Penicillium brevicompactum, primary colonizer; Alternaria tenuissima, secondary colonizer and Trichoderma harzianum, tertiary colonizer, grown on wood were measured for their activities under different relative humidity levels. The activities were measured by isothermal calorimetry. The activities of the moulds changed with the change of the relative humidity levels. The optimal relative humidity levels are different for these three moulds. The mould activities were also different from desorption to adsorption processes under the same relative humidity levels. This might be caused by the moisture hysteresis properties of wood. Therefore, besides of relative humidity, water availability also plays an important role for mould growth. Such information should be taken into account for modelling mould behaviour on building materials.