Application and limitations of a mass transfer VOC emission model for a dry building material

- Styrene emission data from a thermoset composite material were obtained using a small environmental test chamber.
- A mass transfer emission model was used to predict styrene concentration in the chamber.
- The model showed good agreement with the chamber data at 23 °C, but it will require adjustment for other temperatures.

Volatile organic compound (VOC) emission from building materials into air has been quantified, characterized and modeled. Internal diffusion of VOC through a material based on Fick's law of diffusion is the basis for mass transfer modeling of diffusive emission used to estimate VOC concentrations in air over time. Current mass transfer models have been shown to appropriately estimate air VOC concentrations at approximate room temperature, while other research has shown that temperature has a profound effect on the diffusion coefficient, D, of VOC in a material. Here, a mass transfer model is operated at 23 °C and 40 °C using input parameters applicable for each temperature. The model estimates are validated against environmental test chamber data for styrene emission from a vinyl ester resin thermoset composite material. The model correlates well with the 23 °C chamber data, but underestimates chamber data by as much as 10−4 at 264 h for the 40 °C modeling. This suggests that the model requires adjustment for predicting VOC air concentrations at temperatures other than 23 °C.