The FLEC® has been validated and used in research for many years.
Below is a publication list of journal articles, abstracts, poster or oral presentations where the FLEC or CHEMATEC’s other products have been in focus.
If you have anything that can be added to the list, we encourage you to contact CHEMATEC.
2023 |
Braish, Tamara; Tinel, Liselotte; Depelchin, Laurence; Gaudion, Vincent; Andres, Yves; Caudron, Cécile; Antczak, Emmanuel; Brachelet, Franck; Locoge, Nadine Evaluation of the seasonal variation of VOC surface emissions and indoor air concentrations in a public building with bio-based insulation Journal Article In: Building and Environment, vol. 238, pp. 110312, 2023, ISSN: 0360-1323. Abstract | Links | BibTeX | Tags: Bio-based insulations, In-field emissions, Indoor air, Seasonal campaigns, VOC @article{Braish2023,The use of bio-based insulation materials is widely spreading in buildings. Due to their organic load, they can be an important source of Volatile Organic Compounds (VOCs). This study is among the first that evaluates the spatial and seasonal in-field VOC surface emissions from bio-based and conventional building structures as a whole, in a French public building insulated with wood wool. In addition to surface emissions, measurements of VOC concentrations in indoor air were taken. Results showed that a spatial difference (up to 5 times) in VOC emissions was observed due to the inhomogeneity of the surface. Moreover, the cardinal orientation of building structures with the same constitution induced a difference (up to a factor 30) in emission rates due to the exposure to different hygrothermal conditions. The variation in temperature and relative humidity between seasons led to higher summer VOC emissions and indoor air concentrations. In addition, indoor VOC concentrations were shown to be higher at night compared to daytime due to the decreased ventilation rate. Furthermore, an interesting approach was developed in this study to have a primary overview of the impact of surface emissions on indoor VOC levels. Results confirmed that the three bio-based walls have no significant specific VOC emissions at high rates compared to the floor and the ceiling. Bio-based insulations showed no impact on microbial indoor air concentrations during the two seasons. Moreover, no detected VOCs could be attributed to microbial development as they were also emitted from building materials. |
2016 |
Harb, P; Sivachandiran, L; Gaudion, V; Thevenet, F; Locoge, N The 40m3 Innovative experimental Room for INdoor Air studies (IRINA): Development and validations Journal Article In: Chemical Engineering Journal, vol. 306, pp. 568 - 578, 2016, ISSN: 1385-8947. Abstract | Links | BibTeX | Tags: Environmental conditions, Experimental chambers, Indoor air, VOC @article{HARB2016568,Over the last 30years, several experimental chambers were developed and implemented for indoor air studies. Yet, they were not all representative of real indoor air conditions. Either they did not have sufficient volumes or they were hindered by difficulties to control experimental conditions and air exchange rates. In this context, a 40m3 Innovative experimental Room for Indoor Air studies (IRINA) has been developed and validated at Mines Douai (Atmospheric Sciences et Environmental Engineering department (SAGE)) to overcome these drawbacks and above all to perform reproducible indoor air studies avoiding any possible experimental biases. IRINA inner walls are covered with aluminum foils. The room is operated in a closed mode and is equipped with a VOC injection system that relies on the heated and pressurized injection of vaporized VOC. IRINA is also equipped with analytical instruments that allow the analysis of both gas (online and offline measurements) and particle phases. IRINA validation evidenced that: (i) the air exchange rate of the room is well controlled over an one year timespan; (ii) both gaseous and particulate background levels in IRINA remain lower than typical indoor air conditions; (iii) fast homogenization of injected VOC concentrations is reached in the room; (iv) adsorption phenomena on IRINA walls are limited; and (v) there is no VOC matrix impact regarding individual VOC decays. The modelling of VOC natural decay in IRINA based on the new INCA-Indoor model showed that the VOC removal in IRINA is mainly due to the air exchange rate. |
Lyng, Nadja Lynge; Gunnarsen, Lars; Andersen, Helle Vibeke; Kofoed-Sørensen, Vivi; Clausen, Per Axel Measurement of PCB emissions from building surfaces using a novel portable emission test cell Journal Article In: Building and Environment, vol. 101, pp. 77 - 84, 2016, ISSN: 0360-1323. Abstract | Links | BibTeX | Tags: Building materials, emission rate, Emission test cell, Indoor air, Polychlorinated biphenyls (PCBs), Semivolatile organic compound (SVOCs) @article{LYNG201677,Polychlorinated biphenyls (PCBs) were used in building materials like caulks and paints from 1930–1970s and in some cases that caused elevated PCB concentrations in the indoor air at levels considered harmful to occupant health. PCBs are semivolatile organic compounds and capable of spreading from the original source to adjacent materials, indoor air and via adsorption from the air to indoor surfaces, causing secondary contaminations. Remediation of buildings with unsatisfactory indoor air concentrations is a complex and difficult task due to the secondary contamination of building materials and there is a need to prioritise remediation measures on different materials. An inexpensive and portable emission test cell was developed to resemble indoor conditions in relation to the area specific ventilation rate. Emissions were measured using the test cell in the laboratory on freshly made PCB paint. Further, the chamber was used for determining emissions from PCB-containing building materials in the field as well as remediated walls. The measurements showed that sorption of PCBs to chamber walls was insignificant after 2–4 days of exposure to the source. Over a period of two weeks emission rates did not change from any of the tested surfaces, however in the laboratory experiment emission rates decreased over a longer period (48 days) and was most pronounced for the lower chlorinated PCBs. |
2014 |
Vibenholt, Anni; Clausen, Per Axel; Wolkoff, Peder Ozone reaction characteristics of indoor floor dust examined in the emission cell “FLEC” Journal Article In: Chemosphere, vol. 107, pp. 230 - 239, 2014, ISSN: 0045-6535. Abstract | Links | BibTeX | Tags: Aldehydes, FLEC, Floor dust, Indoor air, Ozone, Reaction rate @article{VIBENHOLT2014230,Ozone reacts with C–C double bonds in common indoor VOCs and SVOCs contained in indoor dust and may be catalytically degraded on dust surfaces. The reaction between floor dust and ozone was investigated in the FLEC emission cell at different ozone concentrations and relative humidities (0%, 25%, and 50% RH). One gram of dust was spread on a clean stainless steel plate which was placed in the FLEC. Steady state reaction rate (kDust) at 2.2ppm ozone was determined for four different floor dust samples collected in Danish homes and offices. This high concentration was necessary in order to measure and determine the consumption in the outlet air from the FLEC. Measurements were corrected for FLEC wall effects by subtraction of the steady state reaction rate between ozone and a FLEC on a stainless steel plate without dust (kFLEC). The composition of organic compounds in the dust was analyzed by pressurized liquid extraction and thermal desorption GC–MS before and after ozone exposure. kFLEC was independent of the ozone concentration and the reaction was treated as first order. The same was indicated for kDust since it remained unchanged at 2.2 and 1.6ppm ozone for one dust sample. However, the measured kDust in the FLEC should be considered an average rate constant due to the FLEC geometry. kDust was in the range 0.039–0.14s-1 pr. g dust at 50% RH. kDust was 3 times higher at 25% RH than at 50% RH and 6 times higher than at 0% RH. The inhomogeneity of the dust was assessed by experiments in triplicate with a new portion of dust each time. The relative standard deviation of kDust at 50% RH was 6–20%. The major identified compounds before and after ozone exposure included aldehydes, saturated and unsaturated linear alkanoic acids, benzoic acid and their methyl esters, dimethyl esters, phthalates and traces of α-pinene and limonene. Substantial increase of C7–C9 aldehydes was observed after ozone exposure. |
Poulhet, G; Dusanter, S; Crunaire, S; Locoge, N; Gaudion, V; Merlen, C; Kaluzny, P; Coddeville, P Investigation of formaldehyde sources in French schools using a passive flux sampler Journal Article In: Building and Environment, vol. 71, pp. 111 - 120, 2014, ISSN: 0360-1323. Abstract | Links | BibTeX | Tags: Emission rates, Formaldehyde, Indoor air, Mass balance model, Passive sampling, Public school @article{POULHET2014111,While indoor air quality issues have received increasing attention the past decades, detailed investigations of primary sources of indoor pollution are still difficult to carry out. There is a lack of analytical tools and measurement procedures to identify sources of pollutants and to characterize their emissions. Formaldehyde is a ubiquitous pollutant in indoor environments, which is known to lead to adverse health effects. This study describes a measurement procedure to apportion formaldehyde emissions from building and furnishing materials and presents a source apportionment study performed in French public schools. More than 29 sources of formaldehyde were characterized in each investigated classroom, with higher emissions from building materials compared to furnishing materials. Formaldehyde emission rates measured using passive flux samplers (PFS) range from 1.2 to 252 μg/m2/h, highlighting several strong emitters made of wood products and foam. Interestingly, the ceiling was identified as the main source of formaldehyde in most classrooms. Measured emissions and air exchange rates were constrained in a mass balance model to evaluate the impact of formaldehyde reduction strategies. These results indicate that formaldehyde concentrations can be reduced by 87–98% by removing or replacing the main source of emission by a less emissive material and by increasing the air exchange rate to 1 h−1. In addition, an intercomparison of total emissions calculated from (1) PFS measurements and from (2) measured formaldehyde concentrations and air exchange rates indicate that an unidentified sink of formaldehyde may exist in indoor environments. |
Vibenholt, Anni; Clausen, Per Axel; Wolkoff, Peder Ozone reaction characteristics of indoor floor dust examined in the emission cell “FLEC” Journal Article In: Chemosphere, vol. 107, pp. 230-239, 2014, ISSN: 0045-6535. Abstract | Links | BibTeX | Tags: Aldehydes, FLEC, Floor dust, Indoor air, Ozone, Reaction rate @article{Vibenholt2014d,Ozone reacts with C–C double bonds in common indoor VOCs and SVOCs contained in indoor dust and may be catalytically degraded on dust surfaces. The reaction between floor dust and ozone was investigated in the FLEC emission cell at different ozone concentrations and relative humidities (0%, 25%, and 50% RH). One gram of dust was spread on a clean stainless steel plate which was placed in the FLEC. Steady state reaction rate (kDust) at 2.2ppm ozone was determined for four different floor dust samples collected in Danish homes and offices. This high concentration was necessary in order to measure and determine the consumption in the outlet air from the FLEC. Measurements were corrected for FLEC wall effects by subtraction of the steady state reaction rate between ozone and a FLEC on a stainless steel plate without dust (kFLEC). The composition of organic compounds in the dust was analyzed by pressurized liquid extraction and thermal desorption GC–MS before and after ozone exposure. kFLEC was independent of the ozone concentration and the reaction was treated as first order. The same was indicated for kDust since it remained unchanged at 2.2 and 1.6ppm ozone for one dust sample. However, the measured kDust in the FLEC should be considered an average rate constant due to the FLEC geometry. kDust was in the range 0.039–0.14s-1 pr. g dust at 50% RH. kDust was 3 times higher at 25% RH than at 50% RH and 6 times higher than at 0% RH. The inhomogeneity of the dust was assessed by experiments in triplicate with a new portion of dust each time. The relative standard deviation of kDust at 50% RH was 6–20%. The major identified compounds before and after ozone exposure included aldehydes, saturated and unsaturated linear alkanoic acids, benzoic acid and their methyl esters, dimethyl esters, phthalates and traces of α-pinene and limonene. Substantial increase of C7–C9 aldehydes was observed after ozone exposure. |
2013 |
Hu, Kang; Chen, Qun; Hao, Jun-Hong Influence of suspended particles on indoor semi-volatile organic compounds emission Journal Article In: Atmospheric Environment, vol. 79, pp. 695 - 704, 2013, ISSN: 1352-2310. Abstract | Links | BibTeX | Tags: Adsorption, Indoor air, Semi-volatile organic compounds, Suspended particle, Transport mechanism @article{HU2013695,Semi-volatile organic compounds (SVOCs) have been attracting more and more attentions to many researchers in these years. Because SVOCs have a strong tendency for adsorption to suspended particles, we take the effect of suspended particles into account to study the transport mechanism of SVOCs in the air. We establish a mathematical model to describe the transport mechanism of SVOCs, and study the transport processes of both gas- and particle-phase di-2-ethylhexyl phthalate (DEHP) in Field and Laboratory Emission Cells (FLECs). The predictions by the proposed model not only fit well with the experimental data of previous studies, but also show that the gas-phase DEHP concentration increases rapidly in the first few seconds and increases slowly during the following 200 days due to different transport mechanisms in the two periods. Meanwhile, when the particle radiuses are of the order of micron and the air changes per hour (ACH) is large enough, the characteristic time for DEHP getting gas/particle equilibrium is much longer than the residence time of a particle in the flow field, and thus there is no significant influence of suspended particles on the total concentration of DEHP in the air. Oppositely, the influence of particles on DEHP emission will be enhanced for a cycling air flow system with a small ACH, where increasing ACH will reduce the concentrations of particle-phase SVOCs. Besides, if the particle radiuses are of the order of nanometer, decreasing the particle radiuses will shorter the characteristic time for DEHP getting gas/particle equilibrium, and finally increase the particle-phase concentration of DEHP. |
2012 |
Marć, Mariusz; Zabiegała, Bożena; Namieśnik, Jacek Testing and sampling devices for monitoring volatile and semi-volatile organic compounds in indoor air Journal Article In: TrAC Trends in Analytical Chemistry, vol. 32, pp. 76 - 86, 2012, ISSN: 0165-9936. Abstract | Links | BibTeX | Tags: Air quality, Building material, Direct thermal desorption, emission rate, Emission test chamber, Field and laboratory emission cell, Indoor air, Passive flux sampler, Sampling device, Volatile organic compound @article{MARC201276,Adults spend most of their time in enclosed spaces (e.g., apartment, office and public buildings). According to research conducted by scientists, air quality indoors is much worse than the ambient air quality outdoors. Hazardous chemicals found in air indoors can adversely affect the functioning of the human body and cause many respiratory and circulatory diseases. Harmful chemical compounds (mainly volatile organic compounds and semi-volatile organic compounds) in the indoor environment are present because they are emitted from building and construction materials, and indoor equipment. One way of determining the levels of emissions of harmful chemicals is to use emission test chambers (ETCs), which can optimize analytical parameters (e.g., temperature, humidity, loading factor of the test chamber and the air-exchange rate). This article reviews the literature on the analytical methodologies that are used for different types of ETC for estimating emissions of chemicals from building and construction materials and components of indoor equipment. |
2009 |
Nicolle, Jérôme; Desauziers, Valérie; Mocho, Pierre; Ramalho, Olivier Optimization of FLEC®-SPME for field passive sampling of VOCs emitted from solid building materials Journal Article In: Talanta, vol. 80, no. 2, pp. 730 - 737, 2009, ISSN: 0039-9140. Abstract | Links | BibTeX | Tags: Building material, Emission cell, Indoor air, Passive sampling, SPME, VOC @article{NICOLLE2009730,The FLEC®-SPME sampler, described in a previous paper, consists of an emission cell coupled with solid phase microextraction (SPME) for passive sampling of VOCs emitted from building materials. It represents an interesting alternative to standard dynamic sampling protocol as it is easier to implement. If standard dynamic sampling determines emission rates, passive FLEC®-SPME aims to the determination of the concentration in air at the material surface. That could be assumed provided that material/air equilibrium is reached. Thus, VOCs emission kinetics were studied for 3 different materials (pine wood panel, carpet and PVC floor) to determine equilibrium times. Then, the relevance of the method has been assessed using new materials through a 3-day emission test. Qualitative results were compared to those obtained from the standard method to check the ability of FLEC®-SPME to detect the most toxic compounds, named “VOCs of interest” and listed in the French regulation. Minor differences were observed, so this methodology seems promising, especially for field studies aiming in the identification of VOCs sources in buildings. Moreover, the concentration at the material surface combined to emission modeling could be used to predict indoor VOCs concentrations helping in indoor air quality diagnostic. |
2007 |
Uchiyama, Shigehisa; Matsushima, Erica; Kitao, Nahoko; Tokunaga, Hiroshi; Ando, Masanori; Otsubo, Yasufumi Effect of natural compounds on reducing formaldehyde emission from plywood Journal Article In: Atmospheric Environment, vol. 41, no. 38, pp. 8825 - 8830, 2007, ISSN: 1352-2310. Abstract | Links | BibTeX | Tags: Emission control, Formaldehyde, Indoor air, Natural compounds, Urea @article{UCHIYAMA20078825,The effects of natural compounds on reducing formaldehyde emission from plywood were investigated. Urea, catechin and vanillin were examined as the natural formaldehyde reducers. The microemission cell, with an internal volume of 35ml, the maximum exposed test surface area of 177cm2 and an air purge flow rate of 50mlmin−1, was used to measure specific emission rate (SER). In the case of no reducer treatment, formaldehyde emission from plywood was fast and SERs were 4.4mgm−2h−1 at 30°C and 15mgm−2h−1 at 60°C. When this plywood was treated with the natural compounds, the SERs of formaldehyde were decreased at all temperatures. In the case of urea treatment, the SERs of formaldehyde decreased to 0.30mgm−2h−1 at 30°C and 0.65mgm−2h−1 at 60°C. When the urea treatment was applied to the inside of kitchen cabinet (made from plywood; 270cm wide, 60cm deep, 250cm high), the concentration of formaldehyde was reduced substantially from 1600 to 130μgm−3. The reducing effect of formaldehyde continued during the observation period (6 months), with a mean concentration of 100μgm−3. Reducers in the plywood would react with released formaldehyde. Application of natural compounds such as urea, catechin and vanillin could provide a simple and effective approach for suppressing formaldehyde emission from plywood. |
1999 |
Meininghaus, Roman; Salthammer, Tunga; Knöppel, Helmut Interaction of volatile organic compounds with indoor materials—a small-scale screening method Journal Article In: Atmospheric Environment, vol. 33, no. 15, pp. 2395 - 2401, 1999, ISSN: 1352-2310. Abstract | Links | BibTeX | Tags: FLEC, Indoor air, Mass transport, Permeability, Sink @article{MEININGHAUS19992395,Indoor air pollution caused by volatile organic compounds (VOCs) may affect the health and well-being of inhabitants. Uptake and release of these compounds by and from indoor materials alter their concentrations in indoor air: uptake will lower peak concentrations, whereas subsequent (slow) release at lower concentration levels will prolong the presence of VOCs in indoor air. An experimental set-up has been implemented where indoor materials are placed as a “membrane” separating two air compartments. Both compartments – consisting of Field and Laboratory Emission Cells FLECs – are constantly flushed with air, one air stream containing a mixture of 20 VOCs, and concentrations in both compartments are measured after 1 h. Ten materials usually covering extensive surfaces indoors were consecutively exposed to the vapour mixture at concentration levels typically found in indoor environments. Under the chosen experimental conditions, five of these materials exhibited a permeability high enough that VOCs could be detected on the other side. Mass transport of VOCs into and through indoor materials has therefore been confirmed by experiment. The set-up allows for a quick screening of indoor materials with respect to their sorption capacity and permeability. |