Emission of Volatile Organic Compounds from a Vinyl Floor Covering

Abstract

The emission of volatile organic compounds (VOCs) from a vinyl floor covering has been evaluated in two small climatic chambers and a microchamber using different air exchange rates and loading factors. The concentration versus time emission curves for cyclohexanone and phenol were decreasing. Evaluation of the emission data showed that a first order decay model was insufficient to describe the emission adequately. However, in spite of the different air exchange rates and chamber concentrations, the first order rate constant could be reproduced when the model was fitted to simultaneous measurements in the three chambers. This indicated that the emission was controlled by internal diffusion. A simplified model for emission controlled by internal diffusion in the source was developed, applying a diffusion coefficient which depends exponentially on the concentration in the source. This model described the emission curves satisfactorily. However, the model parameters were not reproducible, probably because the samples were inhomogeneous with respect to VOC content and effective thickness. All results indicated that the concentrations of cyclohexanone and phenol were almost homogeneous at test start (because of the wrapping of the samples during storage prior to testing) and that the emission after a short initial period became controlled by internal diffusion in the source.

Modeling emissions of volatile organic compounds from new carpets

“…Some focused on surface effects (Silberstein et aI., 1988;Dunn and Tichenor, 1988;Tichenor et al, 1991;Clausen et al, 1991;Chang and Guo, 1992), including an example where the boundary layer resistance between the bulk air and the source/sink was taken into account (Axley, 1991), while others considered internal diffusion (Dunn, 1987;Clausen et al, 1992;Dunn and Chen, 1992). Dunn (1987) emphasized the value of such models in de-coupling the source/sink behavior from the experimental apparatus, usually an environmental chamber, so that the results can be applied more widely.…”

“…The diffusion models of Dunn (Dunn, 1987;Dunn and Chen, 1992) assume an infinitely deep source, and can not be used for finite sources that are significantly depleted. Clausen et al (1992) considered a fmite source, but invoked concentration dependent diffusion, which may not be necessary at L1e relatively low concentrations found in the backing in this study. Tney also neglected equilibrium partitioning between the bulk air and the surface of the source as the VOCs in their study had relatively high vapor pressures.…”

Indoor air exposure to volatile compounds emitted by paints: experiment and model

“…In addition, the back pressure approach does contain a sink, the painted surface, because evaporation depends on partial pressure differences between paint and air. Other much used evaporation terms, such as exponential decay ( e.g., Sparks et al, 1991;Clausen et al, 1993 ), double -exponential or second -order decay ( Guo, 1993 ) model emission characteristics regardless of the room concentration. Their disadvantage is that they do not account for the saturation of room air.…”

“…When painting ceases, both the applied volume and area of paint are constant. The painted surface is modeled as a two -compartment system (Figure 1 ), thereby incorporating diffusion of solvents deeper in the paint to the surface, a potentially important rate -limiting process ( Clausen et al, 1993;Dunn and Chen, 1993) , in a simplified way. The upper compartment includes the surface of the paint in contact with air and the lower compartment includes the portion that entered the wooden material.…”

Potential for Reducing Indoor Styrene Exposure from Copied Paper through Use of Low-Emitting Toners

“…This model has been studied to represent, for example, the emissions from dried paint films 9 and vinyl flooring, 10 with n ϭ 2. The emission rates measured here are E 15% (t) (i.e., the rates for paper having 15% coverage).…”