/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://dx.doi.org/10.1034/j. 1600-0668.2001.110406.x Indoor Air, 11, 4, pp. 246-256, 2001-12-01 Sorptive interactions between VOCs and indoor materials Won, D. Y.; Corsi, R. L.; Rynes, M. NRCC-433701 SORPTIVE INTERATIONS BETWEEN VOCS AND INDOOR MATERIALS AbstractA study was completed with various materials (carpet, gypsum board, upholstery, vinyl and wood flooring, acoustic tiles, and fruit) that were exposed to eight gaseous VOCs (isopropanol, MTBE, cyclohexane, toluene, ethylbenzene, tetrachloroethene, 1,2-dichlorobenzene, and 1,2,4-trichlorobenzene) in electro-polished stainless-steel chambers. Dynamic responses in VOC concentrations were used to determine linear adsorption and desorption rate coefficients and equilibrium partition coefficients. A linear adsorption/desorption model was used to effectively describe the interactions between VOCs and indoor surface materials for short-term source events (10 h). Relationships between sorption parameters and chemical vapor pressure and octanol-air partition coefficient were observed. Carpet was identified as the most significant sorptive sink for non-polar VOCs. Virgin gypsum board was observed to be a significant sink for highly polar VOCs. Sorptive interactions between non-polar VOCs and indoor materials were not affected by variations in relative humidity. However, increases in relative humidity were observed to increase the degree of sorption of isopropanol to carpet.Key words: sorptive sinks, volatile organic compounds, indoor air, vapor pressure, octanol-air partition coefficient Practical ImplicationsLinear adsorption/desorption coefficients and equilibrium partition coefficients are provided for a large number of volatile organic compounds (VOCs) and indoor materials. These sorption parameters can be used by modelers to predict the impacts of sorptive materials on indoor air quality, and on occupant exposures to VOCs. The experimental results presented herein clearly 3 demonstrate the relative sorption capacities of various indoor materials, the importance of carpet as a sorptive sink for non-polar VOCs, and the importance of virgin gypsum board for polar VOCs. Such information may be valuable to architects and building designers who wish to minimize or maximize sorptive interactions as a means of influencing indoor air quality. F...

Carpet is generally recognized as a source of volatile organic compounds (VOCs) in indoor air. However, carpet systems can also serve as adsorptive sinks with the potential for reductions in peak VOC concentrations and subsequent re-emission of VOCs over prolonged periods of time. A series of experiments involving eight VOCs, several carpet systems, and environmental conditions were completed using a set of parallel chambers to characterize the sorptive interaction between VOCs and carpet. A linear adsorption/desorption model was observed to be appropriate for short-term sorption events. New carpet fibers treated with stain protection generally accounted for only a small fraction of mass sorbed to carpet. Most of the sorbed mass was accounted for by either the underlying pad (cushion) or a combination of the pad and structural backing. Equilibrium partition coefficients were observed to be correlated to chemical vapor pressure and octanol−air partition coefficient. Variations in relative humidity (RH) had a significant effect on the degree of sorption for a highly soluble VOC (2-propanol). However, RH had little apparent effect on other VOCs. Inlet concentrations generally had little effect on sorption.

a b s t r a c tTo improve the reliability and accuracy of tests used to measure emissions of volatile organic compounds (VOCs) from samples of interior building products, the National Institute of Standards and Technology (NIST) and Virginia Tech (VT) have created a program to develop reference materials with independently predictable emission rates. A diffusive reference material and associated mechanistic model have been developed and are undergoing extensive evaluation. As part of this process, a pilot inter-laboratory study (ILS) was conducted with four laboratories using a polymer material loaded with toluene as the reference source. Results showed the prototype material to be a relatively stable, homogeneous source with consistent emissions both within and between production batches. A comparison of toluene emission rates determined by the laboratories showed relative standard deviations as low as 9%, which are significantly lower than inter-laboratory variations for most previous ILS exercises with VOC sources. At a sample time of 48 h, the mean measured toluene emission rate for all four laboratories was within 1% of the model predicted value. The success of this pilot ILS is a key step toward being able to provide a VOC reference material for independent validation of VOC emission tests conducted in small chambers.Published by Elsevier Ltd.

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/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://dx.doi.org/10.1016/S1352-2310(01)00223-0 Atmospheric Environment, 35, pp. 4479-4488, 2001-04-03 Validation of VALIDATION OF THE SURFACE SINK MODEL FOR SORPTIVE INTERACTIONS BETWEEN VOCS AND INDOOR MATERIALS AbstractAdsorption and desorption by indoor surface materials can have significant impacts on the level of volatile organic compounds (VOCs) indoors. The surface sink model (SSM) was developed to account for these interactions in an indoor air quality model. Two types of scale-up experiments were conducted to validate the SSM that was developed based on small-scale chamber experiments. Conflicting results were obtained from a large-scale laboratory experiment and a field test. From the large-scale laboratory experiment involving three materials and three chemicals, relatively good agreement was observed between measurements and predictions by the SSM. In contrast, the level of sorption in the field test was observed to be at least 9 times greater than was predicted by the SSM.