Improvement of the hazard identification and assessment in application of the Seveso II Directive

International audienceThe Council Directive 96/82/EC of 9 December 1996 on the control of major-accident hazards involving dangerous substances, known as SEVESO II Directive, aims at the prevention of major accidents and the limitation of their consequences for human beings and environment. Although rules are well established to identify potential risk, there is no method to measure the risk level which takes into account safety devices and safety management systems implemented by operators. This paper deals with the first stage of a global methodology that aims to better assess benefits form safety devices and safety management systems through accident scenario selection

Multi-tool formaldehyde measurements in simulated and real atmosphere for indoor air monitoring

International audiencePeople spend most of their time in indoor environments where they can be highly exposed to formaldehyde which is ubiquitous and abundant due to the presence of many emission sources. In French public places, its averaged concentrations can vary from 3 micro g m-3 to 60 micro g m-3. Because formaldehyde is of particular health concern (carcinogenic for human), it is important to be provided with suitable methods to measure its content in indoor air. This work presents the test of five different techniques in the INERIS simulation chamber and in indoor environments: passive and active sampling methods based on 2,4-dinitrophenylhydrazine (DNPH) reaction with formaldehyde, two online continuous monitoring systems based on fluorescence and UV measurements and a portable commercialised analyser based on electrochemical titration. The analytical and sampling problems associated with each measurement method have been identified and will be discussed. An overall agreement between each technique has been observed and continuous analyzers allowed for formaldehyde concentrations change monitoring and secondary formation of that pollutants observation

The effect of agglomeration on the emission of particles from nanopowders flow

International audienceThis paper suggests an original method to evaluate the possible emission of particles from a nanopowder submitted to a shear stress in dense phase and the resulting degree of agglomeration of the particles released. The method is based upon the monitoring of the rheological signature of the nanopowders, thanks to a powder rheometer. As a function of the increasing shear rate, the powder flow will evolve from the newtonian state (dense powder) to the coulombian state (dense rheofluidified phase). If the shear rate is high enough, the powder will be set in suspension and the kinetic state (a leaner dense phase submitted to particles collisions) will be reached. The shear stress in this state is dependent on the particle or the agglomerate diameter for cohesive powders, which can be then calculated from rheograms. Carbon black and silica nanopowders have been tested and compared to other experiments carried out on non cohesive glass beads microparticles, chosen as reference. For the different glass beads powders, the average value of their 'agglomerate' diameter is 12% different of the primary diameter, indicating agglomeration of less than two particles. Nanometric agglomerates were found to be of hundred micrometers diameter. That is in line with the high tendency of the nanoparticles to agglomerate. This work can be used to evaluate the current safety tests, such as Hartmann's tube or 20 L sphere apparatuses, to verify whether the standard equipment for microparticles is suitable for the use of nanoparticles. This is linked to research projects like NanoSafe 2

Pressurisation of fixed roof storage tanks due to external fires

International audienceThis study deals with one of the phenomena which is able to generate fire balls like the one which was observed during the 1987 Edouard Herriot port of Lyon fire. Reflections led on this accident have pushed to consider the phenomenon of tank pressurization as a potential initiating event of the fire ball observed. In concrete terms, when a fixed roof storage tank is surrounded by a pool fire, and when the vents or the insulation are not correctly designed, the inside pressure can raise until the mechanical limits of the structure are reached. The aim of this study is to develop a tool which will allow to follow the variations of the pressure and temperature in the gas phase, highlighting if a pressure increase is possible or not. This will help the sizing of new tank vents and insulation of the walls, or evaluating the risk of already build structures, by solving the question occurrence of the accident, regarding the estimated external fire duration. The model also gives the temperature distribution in the liquid phase, at each time step. In case of rupture, this information will be useful to describe the phenomenological aspect of the accident after the rupture of the tank. It means that qualifying and quantifying the fire ball generated and its effect on persons and structures will be possible. Currently, although a few analytical models exist to quantify the fire ball and its effects after the rupture, none is able to describe with accuracy the pre-rupture phenomena. This model is a work in progress, and at the end, the tool will take into account the two phases of the accident and will allow to study complete and consistent scenarios. After a description of the numerical model developed, this paper presents its application on the study of the influence of various parameters

Considerations about market surveillance and quality control of fireworks

International audienceMost fireworks that are used in Europe and North America are produced by manufacturers located in the Far East. Considering the results of tests performed by the Canadian Explosives Research Laboratory (CERL) and INERIS on fireworks imported into their jurisdictions (mainly from China), and taking into account that a new Directive has been published in 2007 in Europe for the certification of pyrotechnic articles (including fireworks), it has becomes apparent that it is necessary to implement an additional system for examining and certifying the fireworks, when importers themselves are not capable of testing the products in accordance with the existing or newly introduced standards. This system could be applied to manufacturers or control laboratories outside of the European Union, and could be applicable to any country wishing to improve the safety of use of fireworks (safety for consumers and safety during display). We present our views in this paper regarding the proposed system : - a comparison between the examination procedures applied by Canada to imported fireworks and their consequential results, and those applied by France (INERIS) to grab samples taken in the importers warehouses imported fireworks from the far east, and their results - some proposals on criteria of minimal competence (qualified or accredited testing laboratory, competent people, testing equipment, testing procedures, ...) to implement in order to qualify the manufacturers exporting into Europe, or local control bodies

Experimental study of CH4/O2/CO2 mixtures flammability

International audienceThe oxy-combustion process uses CH4/O2/CO2/H2O mixtures at various concentrations, according to the different operation phases. To analyze the risks associated to this process, the safety characteristics of these explosive mixtures have to be taken into account. A literature review showed that some safety features of methane in oxygen or in air were not available. Thus, the flammability ternary diagram of CH4/O2/CO2 mixtures was determined at room temperature and 1 bar pressure. Furthermore, the influence of oxygen content on the explosion severity (Pmax; dP/dt) was investigated. The ternary mixtures were prepared directly in a 20 L spherical test vessel. The concentrations of reactants were adjusted using the relationship between the partial pressure and the molar fraction of gas. The ignition source used was an alumel fusing wire. The flammability limits of methane in oxygen were extrapolated at 5 and 68% vol., by using the established CH4/O2/CO2 mixtures ternary diagram. It also confirmed that when the carbon dioxide concentration increases, the flammability range decreases: no ignition was observed when carbon dioxide content exceeded 73%. A significant influence of the oxygen concentration on the explosion severity has been highlighted for CH4/O2/CO2 mixtures containing respectively 10, 25, 45 and 65% vol. of carbon dioxide. The maximal explosion overpressure and the maximum pressure rise were both measured near the stoechiometry. Maximum values of Pmax and dP/dt measured for a 10% vol. carbon dioxide concentration were 11.2 bar rel. and 5904 bar/s respectively, while they were 3.6 bar rel. and 72 bar/s respectively in the case of a 65% vol. carbon dioxide content in the mixture

Brain aromatase (Cyp19a1b) is a highly sensitive gene to estrogens and xeno-estrogens

International audienceAromatase is the only enzyme responsible for the irreversible conversion of androgens into estrogens. Teleost fishes have two copies of the cyp19a1 gene that encode two isoforms of aromatase: cyp19a1a encodes ovarian aromatase, while the cyp19a1b gene encodes brain aromatase (aromatase B). We have shown that (i) aromatase B is strongly expressed in radial glial cells (RGC), that act as stem cells in mammals and fish and ii) the cyp19a1b gene is very sensitive to estrogens, through a mechanism that involves a well conserved ERE. This feature makes this gene an outstanding biomarker of xeno-estrogen exposures and we have developed and validated an in vivo assay allowing detection of estrogenic activity with a very high sensitivity. The in vivo assay is based on a transgenic zebrafish tg(cyp19a1b-GFP) line that expresses GFP in RGCs and we demonstrate the usefulness of the transgenic cyp19a1b-GFP as a reliable, sensitive and rapid in vivo estrogenic screening assay

Experimental study of accidental industrial LPG releases

International audienceThe objective of the atmospheric dispersion research projects of INERIS are to develop models of flashing releases as encountered in realistic industrial environments. Equivalent source term models exist for flashing release in current long range dispersion models. Several factors can, however, invalidate simplified equivalent source models, especially in the very near field where obstacles can be found. To perform these objectives, INERIS took part in an European project called FLIE (Flashing Liquids in Industrial Environment). In this project, INERIS carried out large-scale experiments with propane and butane releases. The French ministry in charge of Environment also supported INERIS participation which dealt with the modelling of two-phase jets. This paper aims at presenting the large-scale experiments and the main results relative to the rain out observations. The experimental set-up is located in the INERIS test site. It allows performing propane and butane liquid releases at ambient temperature with a regulated pressure from the saturation pressure to 15 bar with an orifice (circular or rectangular shape) of an equivalent diameter from 10 mm to 25 mm. It is possible to realize free jets but also impinging jets by introducing obstacle at a maximum distance of 2 meters from the release point. To develop models requires experimental validation data. Up to now, little of experiments were carried out on a great scale with such a variety of measurements. The results revealed some new points related in particular to the rain-out which are seldom discussed in the literature and which can be useful to develop models of flashing releases. Another important lesson learnt is that pools formed by LPG release jets do not contain liquid exclusively but also a mixture with ice. This has a great influence on the pool evaporation

As transport characterization from the soil to the groundwater : an original laboratory study

International audienceHeavy metals are major soil pollutants since a lot of former industrial soils are polluted by these contaminants. In the context of risk assessment of contaminated sites, they are of particular concern because of their toxicity toward human beings. Nevertheless, the vadose zone of the soil is not taken into consideration in this kind of study, although this is where the pollution enters the soil. That is why mechanisms responsible for trace element release in the unsaturated zone of the soil have to be understood. In addition, tools and methods to measure and put forward interactions between contaminants and the solid matrix have to be provided. Therefore, we selected a soil from a wood preserving facility site (contaminated by As) and decided to follow As release as it was the only trace element measured on site at a concentration in groundwater above the EU guidelines for drinking water quality. We designed an original laboratory set up: two columns were filled with 2 sub-samples of the As contaminated soil (202 and 253mg/kg) and As release was studied as it could occur on site. Two main phenomena were simulated during these experiments: rain water infiltration and an increase in the water table level. After the results of the two experiments, it was shown that As concentrations at the outlet of the two columns were constant over time. Given that and the results of the sequential extraction carried out on this soil, As release could mainly occur from the soluble and exchangeable parts. This will be modeled in a future work in order to confirm this hypothesis

Hazard property classification of waste according to the recent propositions of the EC using different methods

International audienceHazard classification of waste is a necessity, but the hazard properties (named "H" and soon "HP") are still not all defined in a practical and operational manner at EU level. Following discussion of subsequent draft proposals from the Commission there is still no final decision. Methods to implement the proposals have recently been proposed: tests methods for physical risks, test batteries for aquatic and terrestrial ecotoxicity, an analytical package for exhaustive determination of organic substances and mineral elements, surrogate methods for the speciation of mineral elements in mineral substances in waste, and calculation methods for human toxicity and ecotoxicity with M factors. In this paper the different proposed methods have been applied to a large assortment of solid and liquid wastes (>100). Data for 45 wastes documented with extensive chemical analysis and flammability test - were assessed in terms of the different HP criteria and results were compared to LoW for lack of an independent classification. For most waste streams the classification matches with the designation provided in the LoW. This indicates that the criteria used by LoW are similar to the HP limit values. This data set showed HP 14 'Ecotoxic chronic' is the most discriminating HP. All wastes classified as acute ecotoxic are also chronic ecotoxic and the assessment of acute ecotoxicity separately is therefore not needed. The high number of HP 14 classified wastes is due to the very low limit values when stringent M factors are applied to total concentrations (worst case method). With M factor set to 1 the classification method is not sufficiently discriminating between hazardous and non-hazardous materials. The second most frequent hazard is HP 7 'Carcinogenic'. The third most frequent hazard is HP 10 'Toxic for reproduction' and the fourth most frequent hazard is HP 4 "Irritant - skin irritation and eye damage". In a stepwise approach, it seems relevant to assess HP 14 first, then, if the waste is not classified as hazardous, to assess subsequently HP 7, HP 10 and HP 4, and then if still not classified as hazardous, to assess the remaining properties. The elements triggering the HP 14 classification in order of importance are Zn, Cu, Pb, Cr, Cd and Hg. Progress in the speciation of Zn and Cu is essential for HP 14. Organics were quantified by the proposed method (AFNOR XP X30-489) and need no speciation. Organics can contribute significantly to intrinsic toxicity in many waste materials, but they are only of minor importance for the assessment of HP 14 as the metal concentrations are the main HP 14 classifiers. Organic compounds are however responsible for other toxicological characteristics (hormone disturbance, genotoxicity, reprotoxicity...) and shall be taken into account when the waste is not HP 14 classified