Single-layer model to predict the source/sink behavior of diffusion-controlled building materials.

Deept Kumar; John C Little

doi:10.1021/es026332g

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Single-layer model to predict the source/sink behavior of diffusion-controlled building materials.

Deept Kumar·John C Little

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Abstract

Building materials may act as both sources of and sinks forvolatile organic compounds (VOCs) in indoor air. A strategy to characterize the rate of absorption and desorption of VOCs by diffusion-controlled building materials is validated. A previously developed model that predicts mass transfer between a flat slab of material and the well-mixed air within a chamber or room is extended. The generalized model allows a nonuniform initial material-phase concentration and a transient influent gas-phase concentration to be simultaneously considered. An analytical solution to the more general model is developed. Experimental data are obtained by placing samples of vinyl flooring inside a small stainless steel chamber and exposing them to absorption/desorption cycles of n-dodecane and phenol. Measured values for the material-air partition coefficient and the material-phase diffusion coefficient were obtained previously in a series of completely independent experiments. The a priori model predictions are in close agreement with the observed experimental data.

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Absorption Air Pollution, Indoor Construction Materials Diffusion Forecasting Models, Theoretical Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Deept Kumar, John C Little. 2003-09-01. Single-layer model to predict the source/sink behavior of diffusion-controlled building materials.. https://doi.org/10.1021/es026332g

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