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L'objectif de cet article est d'étudier le comportement de gouttelettes de solution d'eau NaCl de 48 µm dans un jet d'air humide avec une vitesse initiale de 5 m.s-1 et une température de 34°C. En utilisant l'anémométrie Doppler laser et l'anémométrie Doppler de phase, nous avons étudié le transport et les gouttelettes dans le jet de gaz en mesurant la décroissance de la vitesse des gouttelettes à différents endroits de la source du jet., The purpose of this paper is to investigate the behavior of 48 µm NaCl-water solution droplets in a humid air jet with an initial velocity of 5 m.s-1 and a temperature of 34°C. Using Laser Doppler Anemometry and Phase Doppler Anemometry, we investigated the transport and of droplets within the gas jet by measuring the decay of droplet velocity at different locations from the jet source.

De nos jours, la détection et la caractérisation des particules de l'air est un enjeu sociétal majeur. Des outils existent pour mesurer la contamination de l'air conformément aux directives et normes en vigueur. Cependant, malgré leurs performances élevées, ils ont des inconvénients tels que leurs encombrements, leurs couts ou encore leurs impossibilités de réaliser des mesures en temps réel. Ainsi ce résumé présente un concept miniaturisé d'un système de détection et de suivi des particules dans l'air comprenant un micro-impacteur combiné à un capteur résonant de type MEMS. Les étapes permettant l'obtention de ce système ainsi que des résultats préliminaires de caractérisation de dépôt de particules seront présentés., Nowadays, the detection and characterization of air particles is a major societal issue. Tools exist to measure air contamination in accordance with the directives and standards. However, despite their high performance, the have disadvantages like their dimensions, their costs or their impossibility to carry out real-time measurements. Thus, this summary presents a miniaturized concept of a system for detecting and monitoring particles in the air comprising a micro-impactor combined with a resonant sensor of MEMS type. The steps allowing this system to be obtained as well as the preliminary results of particle deposition characterization will be presented.

Cet article présente une revue bibliographique des techniques expérimentales utilisées pour la caractérisation des gouttelettes générées lors des différentes activités respiratoires. Ces techniques sont classées en deux catégories : les techniques intrusives et les techniques non intrusives. L'impact du choix de la métrologie sur les paramètres mesurés sera discuté., This article is a review on the experimental techniques used for the characterization of the exhaled droplets generated during different respiratory activities. In this study, these techniques are classified into two categories; intrusive and non-intrusive techniques. The impact of the choice of these measurement techniques on the measured parameters will be discussed.

Nous présentons une étude expérimentale dédiée à la mesure de la fraction d'aérosol remise en suspension dans l'air pendant les opérations de déconstruction du béton, pour des applications en sûreté nucléaire. La quantité totale de particules remises en suspension est évaluée à l'aide de préleveurs à haut débit associés à un compteur optique de particules. Un intérêt particulier est accordé aux particules dans les fractions conventionnelles alvéolaire et thoracique par une analyse de leur distribution granulométrique. Il convient de mentionner que le travail a été réalisé en l'absence de radioactivité. Toutefois, les résultats devraient être facilement transposables aux structures en béton des installations nucléaires exposées au flux neutronique, pour lesquelles les scénarios d'activation sont bien définis., We present an experimental study dedicated to measurement of airborne particle release fraction during concrete dismantling operations for nuclear safety applications. The total re-suspended particles fraction is quantified by using high volume samplers along with an optical particle counter. A particular interest is given to the particles in the respirable and thoracic conventional fractions by particle size distribution analysis. It is noteworthy to mention that the work is realized in absence of radioactivity but the outcomes should be conveniently applicable to concrete structures in nuclear installations exposed to neutron flux, for which activation scenarios are well defined.

The sanitation of concrete structures through dismantling of nuclear buildings is complicated by the radiological threat associated with the airborne release of fine dust. This is the reason why the aerosol release fraction (ARF) associated with mechanical removal of concrete structure containing radioactivity needs to be accurately evaluated to implement efficient radiological survey. We characterize experimentally the ARF resulting from milling operations on a standard concrete slab in a confined experimental chamber using an industrial scarifying machine. Our results reveal a significant production of fine aerosol particles with a mass median aerodynamic diameter close to 4 µm and which mineralogical composition is dominated by calcium and silica compounds. The ARF measured when a vacuum suction device is used to confine the dust production close to the source is on the order of 5×10-4; the maximum ARF estimated when no suction device is used is on the order of 0.5.

Dans ce contexte, de multiples bio-impacteurs sous la forme de buses un étage rondes ont été conçues, fabriquées et caractérisées à partir de considérations classiques dans la conception des impacteurs. Ensuite, des aérosols et bio-aérosols de différentes origines et tailles ont été impactées sur du silicium (lisse) et du silicium nano-structuré pour évaluer les caractéristiques de déposition de ces aérosols sur de telles surfaces. Les résultats expérimentaux montrent que la taille des particules volatiles déterminent les caractéristiques de déposition par un procédé de rebond et de ré-entrainement (effet de rebond). L'efficacité de collecte dans la première zone d'impact a été estimée. Le silicium nano-structuré permet de réduire l'effet de rebond des particules micrométriques grâce à ses piliers pointus en cassant les particules en plus petits fragments ce qui a comme conséquence de confiner la déposition sous la buse. Cette déposition localisée peut facilement être alignée avec un micro-capteur. Ainsi cette étude suggère que les capteurs MEMS de masse inertielle sont adaptés pour la détection de particules de tailles micrométriques.

International audience; A scanning mobility particle sizer (SMPS) is a high resolution nanoparticle sizing system that is widely used as the standard method to measure airborne particle size distributions (PSD) in the size range 1 nm–1 μm. This paper addresses the problem to assess the uncertainty associated with PSD when a differential mobility analyzer (DMA) operates under scanning mode. The sources of uncertainty are described and then modeled either through experiments or knowledge extracted from the literature. Special care is brought to model the physics and to account for competing theories. Indeed, it appears that the modeling errors resulting from approximations of the physics can largely affect the final estimate of this indirect measurement, especially for quantities that are not measured during day-to-day experiments. The Monte Carlo method is used to compute the uncertainty associated with PSD. The method is tested against real data sets that are monosize polystyrene latex spheres (PSL) with nominal diameters of 100 nm, 200 nm and 450 nm. The median diameters and associated standard uncertainty of the aerosol particles are estimated as 101.22 nm ± 0.18 nm, 204.39 nm ± 1.71 nm and 443.87 nm ± 1.52 nm with the new approach. Other statistical parameters, such as the mean diameter, the mode and the geometric mean and associated standard uncertainty, are also computed. These results are then compared with the results obtained by SMPS embedded software.

Le marché des matériaux nanocomposites dédiés au secteur du bâtiment est en constante croissance. Cependant, cette utilisation accrue s'accompagne d'interrogations légitimes quant au devenir de ces nanomatériaux à long terme et à son impact potentiel sur la santé humaine et l'environnement. En effet, la dégradation liée aux mécanismes de vieillissement de ces nanomatériaux est susceptible d'entraîner la dispersion de particules dans l'environnement entraînant, à termes, l'exposition des populations à ces agents physiques. Afin d'apporter de nouvelles connaissances dans ce domaine, nous nous sommes donc intéressé à étudier le relargage particulaire issu de peintures nano-additivé de TiO2 lors de différents scénarios de vieillissement., The market of the nanocomposite materials in the construction industry is growing exponentially. However, many questions are still open concerning the impact of these nanomaterials on the human health and the environment. Their degradations linked by the aging mechanisms could induce the particles released into the environment and thus imply an exposition for the population. In order to provide new scientific knowledge in this topic, we characterized the particles released during the aging scenarios for nano-TiO2-containing paints.

The analytical performance of high-resolution scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX) for accurate determination of the size, size distribution, qualitative elemental analysis of nanoparticles (NPs) was systematically investigated. It is demonstrated how powerful high-resolution SEM is by using both mono- and bi-modal distributions of SiO2 airborne NPs collected on appropriate substrates after their generation from colloidal suspension. The transmission mode of the SEM (TSEM) is systematically employed for NPs prepared on thin film substrates such as transmission electron microscopy grids. Measurements in the transmission mode were performed by using a “single-unit” TSEM transmission setup as manufactured and patented by Zeiss. This alternative to the “conventional” STEM detector consists of a special sample holder that is used in conjunction with the in-place Everhart–Thornley detector. In addition, the EDX capabilities for imaging NPs, highlighting the promising potential with respect to exploitation of the sensitivity of the new large area silicon drift detector energy dispersive X-ray spectrometers were also investigated. The work was carried out in the frame of a large prenormative VAMAS (Versailles Project on Advanced Materials and Standards) project, dedicated to finding appropriate methods and procedures for traceable characterization of NP size and size distribution.

Carbon nanotube-based poly(methyl methacrylate) and polyamide-6 nanocomposites have been investigated using various techniques within the framework of the NANOFEU project. Scanning transmission electron microscopy was used to characterize morphologies of composites, while fire properties were studied using cone calorimeter and pyrolysis combustion flow microcalorimeter. The study focused particularly on composition and microstructure of gaseous and aerosol products. Morphology of ultrafine particles released from the combustion of nanocomposites was studied using cascade impactor and atomic force microscopy. Fire behaviour has been interpreted in relation with the degradation mechanisms specifically induced by the presence of carbon nanotubes. Copyright © 2012 John Wiley & Sons, Ltd.

Nanoparticles with size in the range from 10 nm to 300 nm and from three different materials (Au 10 nm, Ag 20 nm, and PSL 30 nm, 100 nm and 300 nm) were used in this supplementary comparison. The selected nanoparticles meet the requirements of different measurement methods such as Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), and Differential Mobility Analyzer (DMA), Small Angle X-Ray Scattering and for forth. All 37 participating laboratories returned results, but not all laboratories were able to perform measurement of all 5 nanoparticles. In order to determine the degree of equivalence (DOE), two reference values were considered in this comparison: the method dependent reference value (MRV) and the global reference value (GRV). The MRVs were determined for different measurement methods according to the corresponding reported uncertainties and measurement values from the participants. Each measurement method owns its own MRV. Since the measurement data from DLS were very different from and inconsistent with the measurement data from the other methods, the MRV for DLS was used in the En number calculation for the measurement data reported from the DLS method. The GRV was determined from the MRVs and their uncertainties of all the measurement methods except DLS, and was applied in the En number calculations for the measurement data reported from AFM, EM, DMA and SAXS methods. The assumption that the particles are spherical was commonly made in the nanoparticle measurements. Non-sphericity of particles, if exists, could have different impacts on different measurement methods. It is also important to note that the methods used are measuring mean diameters of a population of particles, not just a single particle, and that the meaning of the mean diameter could differ for different methods. Probably if participants include a different specific contribution in the uncertainty in a harmonized way, taking the non-cancelled method-dependent "systematic" errors into account, it may be easier to compare the results. KEY WORDS FOR SEARCH Nanoparticles; Atomic Force Microscopy (AFM); Transmission Electron Microscopy (TEM); Scanning Electron Microscopy (SEM); Dynamic Light Scattering (DLS); and Differential Mobility Analyzer (DMA); Small Angle X-Ray Scattering Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The objective of this work is to carry out an experimental investigation on the influence of different parameters such as liquid properties (viscosity and liquid-gas surface tension), impacting droplet properties (velocity vi and diameter di) and the thickness of liquid film on the emission of airborne particles produced by the impact of millimetre-size droplets onto a liquid film. Our results show that in the variation range studied, the increase of vi and di or the decrease in liquid film thickness produces an increase in the mean number of microdroplets emitted by impact in the size range 2-50 μm. Furthermore, it was also observed that an increase in viscosity involves a steep decrease in the mean number of microdroplets emitted. These microdroplets may be produced by the fingers pinching of the crown formed during impact. In the case of low surface tension liquid, the formation of bubbles involves high production of droplets smaller than 15 μm. The results presented here constitute a database of the micro-droplets produced to validate models of droplet impact outcomes. © 2009 Elsevier Ltd. All rights reserved.

The aim of this work is to carry out an experimental investigation into the generation of airborne microparticles when millimetric droplets of aqueous solutions impact onto a liquid film. Impact experiments using 3.9 mm diameter droplets were carried out for Weber numbers between 159 and 808, with a fixed Ohnesorge number of 2 × 10−3 and film parameters S f (the ratio between the thickness of the liquid film h film and the diameter of the impacting droplet d i) between 0.3 and 1. Observed results show that the deposition/splashing threshold is independent of the parameter S f in agreement with the data in the literature. The aerosol measurement results demonstrate the production of solid particles from the evaporation of secondary microdroplets with diameters less than 30 μm formed when splash occurs. The median diameter of these microdroplets is around 20 μm, corresponding to a value of d 50/d i = 5 × 10−3. Taken together, the results show that the mass and the number of particles emitted increase as the Weber number increases. Moreover, at a Weber number of 808, the results show that the mass and number of particles emitted increases as the parameter S f decreases. In this case, the mean number of microdroplets emitted per impact is equal to 14 for S f = 1 and equal to 76 for S f = 0.3.

Le TEOM-FDMS (Tapered Element Oscillating Microbalance with Filter Dynamics Measurement Systems) est un instrument de mesure tres repandu au sein du reseau national de surveillance de la qualite de l’air. A l’heure actuelle, cet appareil est etalonne a l’aide de masses etalons raccordees au SI mais dont les valeurs et les differences de masse ne sont pas representatives des masses particulaires atmospheriques prelevees. De plus, l’utilisation de ces masses etalons ne permet pas de prendre en compte un eventuel dysfonctionnement du systeme de prelevement en amont de la mesure de la masse et du systeme de filtration intrinseque au TEOM-FDMS. Par consequent, une nouvelle methode d’etalonnage a ete developpee pour les TEOM-FDMS de par la mise en place d’un systeme portable de generation de particules ayant des concentrations massiques connues et stables dans le temps. Cet article presente la caracterisation de la reproductibilite globale de ce generateur portable en terme de gamme de masses de reference, son couplage avec differents types de TEOM-FDMS et la comparaison globale entre les masses particulaires de reference definies et les masses lues obtenues pour chaque TEOM-FDMS implique dans cette etude.

Since the end of the nineties, nanoclays based nanocomposites have been widely studied and produced. These trendy materials are expected to end up in incineration waste plants. Recently, various studies have focused on the particulate emissions of polymer nanocomposites during their combustion [1, 2, 3]. The aim of our work is to investigate the behavior and the fate of the nano-objects from nanocomposites during their incineration. This study focuses on PA6/HNTs nanocomposites (polyamide 6 incorporating halloysite nanotubes). Incineration tests have been performed at lab-scale using a peculiar tubular furnace modified in order to control the key incineration parameters within both the combustion and post-combustion zones [4]. The combustion residues and the combustion aerosol (particle matter and gas phase) collected downstream the incinerator furnace have been characterized using various techniques devoted to the analysis of aerosols. Time tracking for gas concentration and particle number concentration reveals a two step mechanism. HNTs have been found both in aerosol and residues. As shown in Fig.1, some remains intact, while others are aggregated.

International audience; The development, manufacturing and commercialization of nanomaterials require traceable characterisation processes for quality control and safety of both the exposed workers and final customers. Even if the production batches are considered to be compliant with the industrial applications intended by manufacturers, it is necessary to study the reproducibility of the manufacturing process of nanomaterials independently, so as to determine the variability of key physico-chemical properties of nano-objects from one batch to another.In this study, a metrological approach was employed, using different traceable analytical techniques (X-Ray Diffraction, Transmission Electron Microscopy, Nitrogen physisorption with Brunauer–Emmett–Teller method, X-Ray Fluorescence, Scanning Mobility Particle Sizer and Aerodynamic Particle Sizer) to develop robust, reproducible and statistical methods to evaluate the impact of batch variability on physico-chemical properties of manufactured titanium dioxide and silicon dioxide nano-powders (crystalline structure, crystallite size, primary particle size, specific surface area, chemical composition and the dustiness of nanopowders).Five references of manufactured titanium dioxide nanoparticles and silicon dioxide nanoparticles were characterized with the developed measurement protocols. The reproducibilities of five batches by reference were overall inferior to 10% for crystalline structures, primary particle sizes, specific surface areas and the chemical composition of major components (TiO2 and SiO2) of the nanopowders studied (k = 1). As for the size distributions of released particles from dustiness tests, reproducibility for the modal and mean diameters ranged between 2% and 27%. Moreover, a large variation of nanopowder dustiness was obtained for the same material type (TiO2 or SiO2). This could point out that the physico-chemical properties of nanopowders, linked to the manufacturing process, have a strong impact on the dustiness parameter.

International audience; This work investigates the aerosols emitted during combustion of aircraft and naval structural composite materials (epoxy resin/carbon fibers and vinyl ester/glass fibers and carbon nanotubes). Combustion tests were performed at lab-scale using a modified cone calorimeter. The aerosols emitted have been characterized using various metrological devices devoted to the analysis of aerosols. The influence of the nature of polymer matrices, the incorporation of fibers and carbon nanotubes as well as glass reinforcements on the number concentration and the size distribution of airborne particles produced, was studied in the 5 nm–10 μm range. Incorporation of carbon fibers into epoxy resin significantly reduced the total particle number concentration. In addition, the interlaced orientation of carbon fibers limited the particles production compared to the composites with unidirectional one.The carbon nanotubes loading in vinyl ester resin composites influenced the total particles production during the flaming combustion with changes during kinetics emission. Predominant populations of airborne particles generated during combustion of all tested composites were characterized by a PN50 following by PN100–500.

Results of an interlaboratory comparison on size characterization of SiO2 airborne nanoparticles using on-line and off-line measurement techniques are discussed. This study was performed in the framework of Technical Working Area (TWA) 34 - "Properties of Nanoparticle Populations" of the Versailles Project on Advanced Materials and Standards (VAMAS) in the project no. 3 "Techniques for characterizing size distribution of airborne nanoparticles". Two types of nano-aerosols, consisting of (1) one population of nanoparticles with a mean diameter between 30.3 and 39.0 nm and (2) two populations of non-agglomerated nanoparticles with mean diameters between, respectively, 36.2-46.6 nm and 80.2-89.8 nm, were generated for characterization measurements. Scanning mobility particle size spectrometers (SMPS) were used for on-line measurements of size distributions of the produced nano-aerosols. Transmission electron microscopy, scanning electron microscopy, and atomic force microscopy were used as off-line measurement techniques for nanoparticles characterization. Samples were deposited on appropriate supports such as grids, filters, and mica plates by electrostatic precipitation and a filtration technique using SMPS controlled generation upstream. The results of the main size distribution parameters (mean and mode diameters), obtained from several laboratories, were compared based on metrological approaches including metrological traceability, calibration, and evaluation of the measurement uncertainty. Internationally harmonized measurement procedures for airborne SiO2 nanoparticles characterization are proposed. © 2013 Springer Science+Business Media Dordrecht.

International audience; A model to simulate SMPS (Scanning Mobility Particle Sizer) measurement and the associated uncertainty analysis when axial DMA (Di erential Mobility Analyser) classi er operates under scanning mode conditions is de- scribed. Starting from simulated SMPS raw data, a fast estimation of aerosol size distribution measurement using regularization technique is performed. Then, global sensi- tivity analysis is used to discriminate signi cant parameters of the system and, as a preliminary result, a 95% con dence region is obtained by Monte Carlo simulations on an atmo- spheric aerosol size distribution.

The fire behavior and the characterization of solid and gaseous fire effluents of polymers [polymethyl methacrylate (PMMA) and polyamide-6 (PA-6)] filled with nanoparticles (silica, alumina, and carbon nanotubes) used to improve their flame retardancy were investigated. To determine the impact of these composites on the emission of airborne particles produced during their combustion in accidental fire scenarios, an experimental setup was developed to measure the mass distribution in the 30 nm–10 μm range, and the concentrations of submicrometric particles in the aerosol. Comparisons were made between unfilled and filled polymers, and the influence of filler surface treatments (silane-based), as well as combinations with a flame retardant [ammonium polyphosphate (APP)], was investigated. The presence of nano-oxides in PMMA shows a significant effect on the rate of particle emission with a decrease in the concentration of the emitted submicrometric particles. APP in PMMA led to a decrease in the mass fraction of ultrafine particles and an increase in the rate of submicrometric particle emission compared to filled compositions with nano-oxides. Atomic force microscopy was used as a complementary tool for the characterization of the particles emitted during combustion, allowing direct observation of nanoparticle morphology, detection of carbon nanotubes in the aerosol, and visualization of the effect of APP on nanoparticle morphology.

International audience; Impingement of droplets on surfaces occurs in many industrial and natural processes. The study of droplet break-up is fundamental in order to determine the potential sources of airborne contamination for scenarios of hazardous liquid falls such as dripping. There are very few data in the literature describing the case of impact of millimetre-size droplets. The purposes of this work were to study experimentally particle emission during the impact of droplets on a liquid film and to assess the use of coalescence/splash relations to predict airborne particle release. The results are described using dimensionless numbers taking into account the inertial, viscosity and surface tension forces. Experiments were carried out for Weber numbers between 62 and 1754 and for Ohnesorge numbers between 2.0×10 -3 and 1.5×10 -2. New results on coalescence/splash thresholds are obtained using highly sensitive aerosol measurement and allow a prediction concerning the presence or absence of airborne particles according to a threshold relation. Moreover, we propose a modification of the Cossali et al.'s [1] relation in order to describe the coalescence/prompt splash threshold. © 2011 Elsevier Inc.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Technological advances in nanomaterials have allowed the development of new applications in industry, increasing the probability of finding airborne manufactured and engineered nano-objects in the workplace, as well as in ambient air. Scientific studies on health and environmental risks have indicated that airborne nano-objects in ambient air have potential adverse effects on the health of exposed workers and the general population. For regulatory purposes, ambient measurements of particulate matter are based on the determination of mass concentrations for PM10 and PM2.5, as regulated in the European Directive 2008/50/EC. However, this legislation is not suitable for airborne manufactured and engineered nano-objects. Parameters characterising ultrafine particles, such as particle number concentration and size distribution, are under consideration for future health-based legislation, to monitor workplaces and to control industrial processes. Currently, there are no existing regulations covering manufactured airborne nano-objects. There is therefore a clear, unaddressed need to focus on the toxicology and exposure assessment of nano-objects such as titanium dioxide (TiO2), which are manufactured and engineered in large quantities in industry. To perform reliable toxicology studies it is necessary to determine the relevant characteristics of nano-objects, such as morphology, surface area, agglomeration, chemical composition, particle size and concentration, by applying traceable methods. Manufacturing of nanomaterials, and their use in industrial applications, also require traceable characterisation of the nanomaterials, particularly for quality control of the process. The present study arises from the OECD WPMN sponsorship programme, supported by the French Agency for Environmental and Occupational Health Safety (ANSES), in order to develop analytical methods for the characterization of TiO2 nanoparticles in size and count size distribution, based on different techniques to characterize five different manufactured TiO2 nanoparticles. In this study, different measurement techniques have been implemented: Transmission Electron Microscopy (TEM), Scanning Mobility Particle Sizer (SMPS) and Aerodynamic Particle Sizer (APS). The TEM results lead to a relatively good agreement between data from the manufacturer and our characterizations of primary particle size. With regard to the dustiness, the results show a strong presence of agglomerates / aggregates of primary particles and a significant presence of emitted airborne nanoparticles with a diameter below 100 nm (composed of isolated primary particles and small aggregates / agglomerates formed from a few primary particles): the number proportion of these particles varies from 0 to 44 % in the measurement range 14-360 nm depending on the types of powders and corrections of measurements.

Scanning Mobility Particle Sizer (SMPS) is a high resolution nanoparticle sizing system that has long been hailed as the researcher's choice for airborne nanoparticle size characterization for nano applications including nanotechnology research and development. SMPS is widely used as the standard method to measure airborne particle size distributions below 1 m. It is composed of two devices: a Dierential Mobility Analyzer (DMA) selects particle sizes thanks to their electrical mobility and a Condensation Particle Counter (CPC) enlarges particles to make them detectable by common optical counters. System raw data represent the number of particles counted over several classes of mobility diameters. Then, common inversion procedures lead to the estimation of the aerosol size distribution. In this paper, we develop a methodology to compute the uncertainties associated with the estimation of the size distribution when several experiences have been carried out. The requirement to repeat the measure ensures a realistic variability on the simulated data to be generated. The work we present consists in considering both the uncertainties coming from the experimental dispersion and the uncertainties induced by the lack of knowledge on physical phenomena. Experimental dispersion is quantied with the experimental data while the lack of knowledge is modelled via the existing physical theories and the judgements of experts in the eld of aerosol science. Thus, running Monte-Carlo simulations give an estimation of the size distribution and its corresponding condence region.

Day after day, new applications using nanoparticles appear in industry, increasing the probability to find these particles in the workplace as well as in ambient air. As epidemiological studies have shown an association between increased particulate air pollution and adverse health effects in susceptible members of the population, it is particularly important to characterize aerosols emitted by different sources of emission, during the combustion of composites charged with nanoparticles for example. The present study is led in the framework of the NANOFEU project, supported by the French Research Agency (ANR), in order to characterize the fire behaviour of polymers charged with suitable nanoparticles and make an alternative to retardant systems usually employed. To determine the impact of these composites on the emission of airborne particles produced during their combustions, an experimental setup has been developed to measure the mass distribution in the range of 30 nm – 10 μm and the number concentration of submicrometric particles of the produced aerosol. A comparison is performed on the aerosol emitted during the combustion of several polymers alone (PMMA, PA-6), polymers containing nanofillers (silica, alumina, and carbon nanotubes) and polymers containing both nanofillers and a conventional flame retardant system (ammonium polyphosphate). The results on the morphology of particles were also investigated using AFM.