Publications

@article{WEI2018223,

title = {Influence of indoor environmental factors on mass transfer parameters and concentrations of semi-volatile organic compounds},

author = {Wenjuan Wei and Corinne Mandin and Olivier Ramalho},

url = {http://www.sciencedirect.com/science/article/pii/S0045653517320428},

doi = {https://doi.org/10.1016/j.chemosphere.2017.12.072},

issn = {0045-6535},

year  = {2018},

date = {2018-01-01},

journal = {Chemosphere},

volume = {195},

pages = {223 - 235},

abstract = {Semi-volatile organic compounds (SVOCs) in indoor environments can partition among the gas phase, airborne particles, settled dust, and available surfaces. The mass transfer parameters of SVOCs, such as the mass transfer coefficient and the partition coefficient, are influenced by indoor environmental factors. Subsequently, indoor SVOC concentrations and thus occupant exposure can vary depending on environmental factors. In this review, the influence of six environmental factors, i.e., indoor temperature, humidity, ventilation, airborne particle concentration, source loading factor, and reactive chemistry, on the mass transfer parameters and indoor concentrations of SVOCs was analyzed and tentatively quantified. The results show that all mass transfer parameters vary depending on environmental factors. These variations are mostly characterized by empirical equations, particularly for humidity. Theoretical calculations of these parameters based on mass transfer mechanisms are available only for the emission of SVOCs from source surfaces when airborne particles are not present. All mass transfer parameters depend on the temperature. Humidity influences the partition of SVOCs among different phases and is associated with phthalate hydrolysis. Ventilation has a combined effect with the airborne particle concentration on SVOC emission and their mass transfer among different phases. Indoor chemical reactions can produce or eliminate SVOCs slowly. To better model the dynamic SVOC concentration indoors, the present review suggests studying the combined effect of environmental factors in real indoor environments. Moreover, interactions between indoor environmental factors and human activities and their influence on SVOC mass transfer processes should be considered.},

keywords = {Emission, Mass transfer, Modeling, Partition, SVOCs},

pubstate = {published},

tppubtype = {article}

}

@article{XIONG2016314,

title = {Early stage C-history method: Rapid and accurate determination of the key SVOC emission or sorption parameters of indoor materials},

author = {Jianyin Xiong and Jianping Cao and Yinping Zhang},

url = {http://www.sciencedirect.com/science/article/pii/S0360132315301360},

doi = {https://doi.org/10.1016/j.buildenv.2015.09.027},

issn = {0360-1323},

year  = {2016},

date = {2016-01-01},

journal = {Building and Environment},

volume = {95},

pages = {314 - 321},

abstract = {The accurate and rapid determination of the emission parameters of semi-volatile organic compounds (SVOCs) from indoor materials is of great importance for estimating and controlling indoor exposure. By virtue of a simplified mass transfer model we derived, a new method called the early stage C-history method, has been developed to measure the key emission parameters: the gas phase SVOC concentration adjacent to the material surface (y0) and the convective mass transfer coefficient (hm). We validate this model using experimental data found in the literature. When compared with established methods, the new method has the following salient features: (1) rapid (the experimental time is reduced from several months to several days); (2) accurate (R2 in the range of 0.92–0.97). Further analysis shows that both features can be further improved if the test system has a smaller chamber wall/air partition coefficient. The new method is also extended to measure the key parameters of SVOCs from sorption materials. This method should prove useful for screening SVOC emission characteristics and for assessing exposure, as well as for chamber and test design.},

keywords = {Emission, Indoor air quality, Key parameters, Semi-volatile organic compounds (SVOCs), Sorption},

pubstate = {published},

tppubtype = {article}

}

@article{LIU2016283,

title = {Characterizing the equilibrium relationship between DEHP in PVC flooring and air using a closed-chamber SPME method},

author = {Cong Liu and Yinping Zhang},

url = {http://www.sciencedirect.com/science/article/pii/S0360132315301372},

doi = {https://doi.org/10.1016/j.buildenv.2015.09.028},

issn = {0360-1323},

year  = {2016},

date = {2016-01-01},

journal = {Building and Environment},

volume = {95},

pages = {283 - 290},

abstract = {The di-(2-ethylhexyl) phthalate (DEHP) concentration in the air immediately adjacent to a polyvinyl chloride (PVC) flooring surface, y0 (μg/m3), has been identified as one of the critical parameters governing the emission process and consequent exposure. At room temperature and below, the relationship between y0 and the vapor pressure of pure DEHP (Psat) is still unclear. Few studies have been conducted to examine the influence of the mass fraction of DEHP in PVC on the relationship. In this study a new closed-chamber solid phase microextraction (SPME) method is developed to characterize ratio of y0 to Psat at 23 °C. This method avoids the artifact from wall-loss of sampling lines and of the thermal desorption system, in contrast to ventilated-chamber methods. Results show that at 23 °C y0 is significantly lower than the vapor pressure of pure DEHP. When the mass fraction of DEHP in PVC flooring increases from 13% to 23%, y0/Psat is increased by 7.2%, similar to what is reported in the literature. The sorption capacity of SPME stainless steel (SS) rods differs by up to 104%, although they are all made of SS. Based on error analysis, strategies are recommended to improve the precision and time efficiency. The method developed here should work for other SVOC-polymer systems.},

keywords = {Emission, Indoor air quality (IAQ), Mass transfer, Persistent organic pollutants (POPs), Semivolatile organic compound (SVOC)},

pubstate = {published},

tppubtype = {article}

}

@article{LIANG2015141,

title = {Large-scale chamber investigation and simulation of phthalate emissions from vinyl flooring},

author = {Yirui Liang and Olivier Caillot and Jianshun Zhang and Jiping Zhu and Ying Xu},

url = {http://www.sciencedirect.com/science/article/pii/S0360132315000797},

doi = {https://doi.org/10.1016/j.buildenv.2015.02.022},

issn = {0360-1323},

year  = {2015},

date = {2015-01-01},

journal = {Building and Environment},

volume = {89},

pages = {141 - 149},

abstract = {This study investigated phthalate emissions from vinyl flooring in a large-scale chamber. Vinyl flooring materials were examined for their phthalates content; one with high contents of diisononyl phthalate (DINP) and di(2-ethylhexyl) phthalate (DEHP) was selected for emissions testing in a small chamber at two different temperatures. Using the same type of vinyl flooring, large-scale chamber experiments were then conducted in three testing phases. In the first phase, the gas-phase concentrations of DINP and DEHP in the large chamber at 36 °C were about three times lower than those in the small chamber under the same temperature, which is consistent with its lower area/volume ratio. In the second phase, when a large air mixing fan inside the chamber was replaced with a small fan, the gas-phase concentrations of DINP and DEHP in the large chamber were reduced slightly, due to the decease of mass transfer coefficient and emission rate. During the last phase, when the temperature of the chamber was reduced to 25 °C, phthalate concentrations dropped instantly and steeply due to the significantly reduced emissions. However, they did not decrease as quickly thereafter because of desorption of phthalates from the internal surfaces of the large chamber. A fundamental mechanistic model was developed to interpret the experimental results in the large chamber based on the emission characteristics obtained in the small chamber measurements. Reasonable agreement was obtained between the model calculation and experimental data. Further model simulations show that temperature and air mixing above the source material have important effects on the fate of phthalates, while the impact of air change rate (ACH) is not significant.},

keywords = {Emission, Large-scale chamber, Modeling, Phthalates, Sorption, SVOCs},

pubstate = {published},

tppubtype = {article}

}

@article{XIONG201365,

title = {Measuring the characteristic parameters of VOC emission from paints},

author = {Jianyin Xiong and Lixin Wang and Yuhua Bai and Yinping Zhang},

url = {http://www.sciencedirect.com/science/article/pii/S0360132313001364},

doi = {https://doi.org/10.1016/j.buildenv.2013.04.025},

issn = {0360-1323},

year  = {2013},

date = {2013-01-01},

journal = {Building and Environment},

volume = {66},

pages = {65 - 71},

abstract = {The emission characteristic parameters of volatile organic compounds (VOCs) from paints are the initial concentration, the diffusion coefficient and the paint/air partition coefficient. It is necessary to determine these parameters for fully understanding the emission behaviors as well as for source control. Based on detailed mass transfer analysis of VOC emissions from paints, a novel method is developed to measure these parameters, which owns the following merits: (1) the diffusion coefficient and partition coefficient can be simultaneously determined; (2) it takes less than 12 h for the cases studied and indicates high measurement accuracy (R2 in the range of 0.921–0.939). Ventilated chamber experiments are performed to obtain the two parameters of methylcyclohexane and toluene emissions from one kind of solvent-based paint. The effectiveness of the method is verified by the good agreement between model predictions based on the determined characteristic parameters and experiments. The present approach is then applied to analyze the experimental data in the literature, and good results are also obtained, which further demonstrates that the approach is convincing and reliable. Our new approach should prove useful for rapid prediction and characterization of VOC emissions from paints as well as from other wet materials.},

keywords = {Characteristic parameters, Emission, Indoor air quality (IAQ), Paints, Volatile organic compounds (VOCs)},

pubstate = {published},

tppubtype = {article}

}

@article{GUO2013908,

title = {Formaldehyde concentration and its influencing factors in residential homes after decoration at Hangzhou, China},

author = {Min Guo and Xiaoqiang Pei and Feifei Mo and Jianlei Liu and Xueyou Shen},

url = {http://www.sciencedirect.com/science/article/pii/S1001074212601703},

doi = {https://doi.org/10.1016/S1001-0742(12)60170-3},

issn = {1001-0742},

year  = {2013},

date = {2013-01-01},

journal = {Journal of Environmental Sciences},

volume = {25},

number = {5},

pages = {908 - 915},

abstract = {Air pollution surveys of formaldehyde (HCHO) were conducted in 2324 rooms decorated within one year in 2007–2009 in Hangzhou, China. The mean HCHO concentration (CHCHO) was 0.107 ± 0.095 mg/m3, and 38.9% of samples exceeded the Chinese National Standard GB 50325-2010. Over the past 3 years, the CHCHO decreased with time (p < 0.05). Relationships of potential factors to indoor CHCHO were also evaluated. CHCHO was related to temperature (T), relative humidity (RH), time duration of the windows and doors being closed before sampling (DC), time duration from the end of decoration to sampling (DR) and source characteristics (d). A model to relate indoor CHCHO to these five factors (T, RH, DC, DR, d) was established based on 298 samples (R2 = 0.87). Various factors contributed to CHCHO in the following order: T, 43.7%; d, 31.0%; DC, 10.2%; DR, 8.0%; RH, 7.0%; specifically, meteorological conditions (i.e., RH plus T) accounted for 50.7%. The coefficient of T and RH, RTH, was proposed to describe their combined influence on HCHO emission, which also had a linear relationship (R2 = 0.9387) with HCHO release in a simulation chamber test. In addition, experiments confirm that it is a synergistic action as T and RH accelerate the release of HCHO, and that is a significant factor influencing indoor HCHO pollution. These achievements could lead to reference values of measures for the efficient reduction of indoor HCHO pollution.},

keywords = {Emission, factor analysis, Formaldehyde, Indoor air quality, relative humidity, temperature},

pubstate = {published},

tppubtype = {article}

}

@article{WANG20111026,

title = {Measuring chemical emissions from wet products—Development of a new measurement technique},

author = {Rong Wang and Jiping Zhu and Soheil Rastan and Fariborz Haghighat},

url = {http://www.sciencedirect.com/science/article/pii/S0304389411007667},

doi = {https://doi.org/10.1016/j.jhazmat.2011.06.004},

issn = {0304-3894},

year  = {2011},

date = {2011-01-01},

journal = {Journal of Hazardous Materials},

volume = {192},

number = {3},

pages = {1026 - 1032},

abstract = {A new approach for estimating chemical emissions from wet products has been developed. The concept of such approach is that emission rates can be estimated from the amount of target chemicals in the product as a function of evaporation time. Samples were placed under a laboratory fume hood under controlled conditions (surface air velocity and temperature). Weight losses of the product were monitored and residuals at different time intervals were chemically analyzed. Emission factors of the target chemicals were then calculated based on the weight losses and residual levels of the chemicals. To demonstrate the applicability of this approach, two wet products with very different physical characteristics, one liquid and one paste-like viscous fluid, were chosen. Emissions of two principle chemicals in the products, decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) were measured. The influences of initial sample weight, surface air velocity, and temperature were investigated. The calculated emission profiles were compared with those obtained from the chamber method. The described approach could be used as an alternative screening method for emission tests of wet products, especially for compounds with low vapour pressure when sink effect poses serious challenge in traditional chamber-based emission tests.},

keywords = {Emission, Measurement techniques, Test chamber, Weigh loss, Wet products},

pubstate = {published},

tppubtype = {article}

}

@article{CLAUSEN20102760,

title = {Influence of air flow rate on emission of DEHP from vinyl flooring in the emission cell FLEC: Measurements and CFD simulation},

author = {Per Axel Clausen and Zhe Liu and Ying Xu and Vivi Kofoed-Sørensen and John C Little},

url = {http://www.sciencedirect.com/science/article/pii/S135223101000302X},

doi = {https://doi.org/10.1016/j.atmosenv.2010.04.020},

issn = {1352-2310},

year  = {2010},

date = {2010-01-01},

journal = {Atmospheric Environment},

volume = {44},

number = {23},

pages = {2760 - 2766},

abstract = {The emission of di-(2-ethylhexyl)phthalate (DEHP) from one type of vinyl flooring with ∼15% (w/w) DEHP as plasticizer was measured at 22 °C in five FLECs + one blank FLEC (Field and Laboratory Emission Cell). Initially, the flow through all FLECs was 450 ml min−1. After 689 days the flows were changed to 1000 ml min−1, 1600 ml min−1, 2300 ml min−1, and 3000 ml min−1, respectively, in four FLECs, and kept at 450 ml min−1 in one FLEC. Air samples were collected from the effluent air at regular intervals. After 1190 days the experiments were terminated and the interior surfaces of all six FLECs were rinsed with methanol to estimate the internal surface concentrations of DEHP. The DEHP air concentration and specific emission rate (SER) at steady state was estimated for the five different flow rates. The steady-state concentrations decreased slightly with increasing air flow with only the two highest flow rates resulting in significantly lower concentrations. In contrast, the SERs increased significantly. Despite large variation, the internal surface concentrations appeared to decrease slightly with increasing FLEC flow. Computational fluid dynamic (CFD) simulations suggest that the interior gas and surface concentrations were roughly uniform for the low flow case (450 ml min−1), under which, the partitioning between the FLEC internal surface and chamber air was examined. Although paired t-tests showed no difference between CFD and experimental results for DEHP air concentrations and SERs at steady-state conditions, CFD indicated that the experimental DEHP surface concentrations in the FLECs were underestimated. In conclusion, the experiments showed that the emission of DEHP from vinyl flooring is subject to “external” control and that the SER is strongly and positively dependent on the air exchange rate. However, the increased SER almost compensates for the decrease in gas-phase concentration caused by the increased air exchange.},

keywords = {CFD, Chamber, DEHP, Emission, FLEC, PVC},

pubstate = {published},

tppubtype = {article}

}

@article{KAGI20091199,

title = {Secondary VOC emissions from flooring material surfaces exposed to ozone or UV irradiation},

author = {N Kagi and S Fujii and H Tamura and N Namiki},

url = {http://www.sciencedirect.com/science/article/pii/S0360132308002199},

doi = {https://doi.org/10.1016/j.buildenv.2008.09.004},

issn = {0360-1323},

year  = {2009},

date = {2009-01-01},

journal = {Building and Environment},

volume = {44},

number = {6},

pages = {1199 - 1205},

abstract = {Chemical reactions on the surface of building materials can lead to secondary emissions from these materials that influence indoor air quality. Many studies have been made on the physical processes that influence material emissions. However, there are only a few studies on secondary emissions resulting from exposure of building material surfaces to ozone or ultraviolet (UV) irradiation. Therefore, this study was aimed at elaborating on the emission of chemicals resulting from chemical reactions initiated by the exposure of the surface of flooring materials to ozone or UV irradiation. The laboratory tests were conducted to estimate gas-phase emissions from the flooring materials when they were exposed to ozone or various kinds of light irradiation (infrared, sunlight, UV-A and UV-B lamps). The infrared and sunlight lamps significantly increased the temperature of the test specimens and, in turn, increased the emission rate for various organic compounds. The flooring materials used in this study had been treated with UV-cured surface coatings during their manufacturing. As a result, when exposed to UV irradiation, chemical transformations occurred resulting in the emission of a number of secondary products, including formaldehyde, acetaldehyde, cyclohexanone and benzaldehyde. Ozone reacted with chemicals present in the flooring materials to increase the emission rates of formaldehyde and acetaldehyde. Hence, the exposure of ozone and UV irradiation increased the secondary emissions of formaldehyde, even though the low formaldehyde emission type of flooring material was employed.},

keywords = {Chamber test, Emission, Secondary emission, Volatile organic compounds},

pubstate = {published},

tppubtype = {article}

}

@article{WESTBERG2009914,

title = {Quality assessment of building products by the micro-scale headspace vial (MHV) method and HS-SPME for monitoring the emission of hydrolysis products from phthalates},

author = {Åsa Westberg and Dane Momcilovic and Folke Björk and Sigbritt Karlsson},

url = {http://www.sciencedirect.com/science/article/pii/S0141391009000846},

doi = {https://doi.org/10.1016/j.polymdegradstab.2009.03.002},

issn = {0141-3910},

year  = {2009},

date = {2009-01-01},

journal = {Polymer Degradation and Stability},

volume = {94},

number = {6},

pages = {914 - 920},

abstract = {2-Ethyl hexanol from hydrolysed di-octyl-phthalate (DOP) may cause a secondary emission from building products such as PVC carpets and/or glues causing indoor air pollution. In the present study, a micro-scale headspace vial (MHV) method, earlier developed by us, was refined to study the degradation of DOP and di-isononyl phthalate (DINP) in humid and alkaline environments. By HS-SPME it was possible to extract the degradation products at low temperature, 35°C, which limits the risks of unwanted degradation during sampling. Three different types of HS-SPME fibres were evaluated. The carbowax-divinyl benzene (CW/DVB) fibre had the highest extraction capacity of 2-ethyl-1-hexanol and 5-nonanol. Although significantly shorter extraction times could be used with the 7μm and 30μm poly-dimethylsiloxane (PDMS) fibres, the CW/DVB fibre was found to be the most suitable for these alcohols. Furthermore, it was found that pH of the alkaline environment strongly influences the formation of degradation products from DOP and DINP.},

keywords = {Degradation, Emission, HS-SPME, Micro-scale chamber, phthalate},

pubstate = {published},

tppubtype = {article}

}

@article{CLAUSEN20073217,

title = {The influence of humidity on the emission of di-(2-ethylhexyl) phthalate (DEHP) from vinyl flooring in the emission cell “FLEC”},

author = {Per Axel Clausen and Ying Xu and Vivi Kofoed-Sørensen and John C Little and Peder Wolkoff},

url = {http://www.sciencedirect.com/science/article/pii/S1352231006011460},

doi = {https://doi.org/10.1016/j.atmosenv.2006.06.063},

issn = {1352-2310},

year  = {2007},

date = {2007-01-01},

journal = {Atmospheric Environment},

volume = {41},

number = {15},

pages = {3217 - 3224},

abstract = {Asthma in children appears to be associated with both phthalate esters and dampness in buildings. An important question is whether the concentrations of phthalate esters correlate with dampness (expressed as relative humidity—RH) in indoor air. The objective was to study the influence of RH on the specific emission rate (SER) of di-(2-ethylhexyl)phthalate (DEHP) from one type of vinyl flooring in the well characterized Field and Laboratory Emission Cell (FLEC). The vinyl flooring with ca. 17% (w/w) DEHP as plasticizer was tested in 6 FLECs at 22°C. The RH in the 6 FLECs was 10%, 30%, 50% (in triplicate) and 70%. The RH was changed after 248d in 2 of the 50%-FLECs to 10% and 70%, and to 50% in the 10%-and 70%-FLECs. The data show that the SER of DEHP from vinyl flooring in FLECs during a 1yr period is independent of the RH. A new physically based emission model for semivolatile organic compounds was found to be consistent with the experimental data and independent of the RH. The model helps to explain the RH results, because it appears that RH does not significantly influence any of the identified controlling mechanisms.},

note = {Indoor Air 2005 - 10th International Conference on Indoor Air Quality and Climate (Part I)},

keywords = {DEHP, Emission, Humidity, Plasticizer, Vinyl flooring},

pubstate = {published},

tppubtype = {article}

}

@article{QIAN2007352,

title = {Dimensionless correlations to predict VOC emissions from dry building materials},

author = {Ke Qian and Yinping Zhang and John C Little and Xinke Wang},

url = {http://www.sciencedirect.com/science/article/pii/S1352231006008338},

doi = {https://doi.org/10.1016/j.atmosenv.2006.07.042},

issn = {1352-2310},

year  = {2007},

date = {2007-01-01},

journal = {Atmospheric Environment},

volume = {41},

number = {2},

pages = {352 - 359},

abstract = {Based on the most recently published mass transfer model of volatile organic compound (VOC) emissions from dry building materials, it is found that the dimensionless emission rate and total emission quantity are functions of just four dimensionless parameters, the ratio of mass transfer Biot number to partition coefficient (Bim/K), the mass transfer Fourier number (Fom), the dimensionless air exchange rate (Nδ2/Dm) and the ratio of building material volume to chamber or room volume (Aδ/V). Through numerical analysis and data fitting, a group of dimensionless correlations for estimating the emission rate from dry building materials is obtained. The predictions of the correlations are validated against the predictions made by the mass transfer model. Using the correlations, the VOC emission rate from dry building materials can be conveniently calculated without having to solve the complicated mass transfer equations. Thus it is very simple to estimate VOC emissions for a given condition. The predictions of the correlations agree well with experimental data in the literature except in the initial few hours. Furthermore, based on the correlations, a relationship between the emission rates of a material in two different situations is deduced. With this relationship, the results for a given building material in a test chamber can be scaled to those under real conditions, if the dimensionless parameters are within the appropriate region for the correlations. The relationship also explicitly explains the impacts of air velocity, load ratio, and air exchange rate on the VOC emission rate, which determines the feasibility of assuming that the VOC emission rates in real conditions are the same as those in the test chambers.},

keywords = {Dimensionless correlations, Dry building material, Emission, Volatile organic compounds (VOCs)},

pubstate = {published},

tppubtype = {article}

}

@article{LI20061317,

title = {A physically-based model for prediction of VOCs emissions from paint applied to an absorptive substrate},

author = {Feng Li and Jianlei Niu and Lizhi Zhang},

url = {http://www.sciencedirect.com/science/article/pii/S0360132305001939},

doi = {https://doi.org/10.1016/j.buildenv.2005.05.026},

issn = {0360-1323},

year  = {2006},

date = {2006-01-01},

journal = {Building and Environment},

volume = {41},

number = {10},

pages = {1317 - 1325},

abstract = {Paints are widely used in residential and commercial buildings. The surface areas covered by this kind of coatings are usually very large. The volatile organic compounds (VOCs) emissions from such kind of materials will affect indoor air quality decisively. A relatively simple but physically-based model was developed to simulate VOCs emissions from paints. The model parameters have distinct physical meanings and thus the model is easy to scale up. The field and laboratory emission cell (FLEC) was used to investigate the VOCs emissions from commercially available water-based emulsion paint. Totally 23 individual VOCs were detected and quantified, the most abundant VOC was 1-ethyl-3-methylbenzene. Test data were used to obtain model parameters and to validate the proposed model. Good agreements between experimental data and model predictions were evidenced. Paints applied on two different substrates aluminium and particle board were simulated. Results indicated that real substrates like particle board would act like a ‘sponge’, which lowers the peak concentration but prolongs the presence of VOCs from the applied paint.},

keywords = {Building material, Emission, Field and laboratory emission cell (FLEC), Indoor air quality, Mass transfer, Volatile organic compounds},

pubstate = {published},

tppubtype = {article}

}