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Indoor laundry drying: a full-scale characterization of water emission
No full textInternational audienc
Concrete properties at high temperature. Complete characterization of a HPC concrete: M100
No full textThe report presents concretes properties at high temperature of a High Performance concrete (HPC) M100. These properties have been studied extensively in the frame of the National French Project HPC 2000. The report provides the composition of the concrete and its constituents, mass transport properties (porosity, permeability...), thermal properties, mechanical properties (strength, thermal strain, transient thermal strain, fracture energy...). In addition, the report includes the results from pore pressure and mass loss measurements (PTM) at high temperature. Finally, several tests have been carried out on fire exposed large-scale specimens, beams, columns and walls
Thermal conductivity parallel and perpendicular to fibers direction and heat capacity measurements of eight wood species up to 160 °C
No full textInternational audienceThe aim of this work was to characterize the thermal properties of wood prior to pyrolysis. The Anisotropic Parallel Hot Wire (APHW) technique was applied to characterize 8 wood species with densities varying between 100 and 1000 kg m−3. This variant of the hot wire technique allows the simultaneous measurement of the transverse and longitudinal thermal conductivity and the volumetric heat capacity of wood. Measurements were performed at 4 different temperatures: 20, 60, 110 and 160 °C. The results show that the thermal conductivity in both directions is independent of the type of wood (hardwood or softwood) and it increases linearly with density. Furthermore, the measurements show that the transverse thermal conductivity increases with temperature in contrast to the longitudinal conductivity which is either independent or decreases slightly with the temperature. Therefore, the anisotropy factor decreases with the temperature. The effect of water was also studied by characterizing the same samples at 20 and 60 °C, wet (water content 10%) and dried. The latter results show that thermal conductivity increases with the moisture content. Meanwhile, the effect of water is larger in the transverse direction. The heat capacity was also measured by the Differential Scanning Calorimetry (DSC) technique between 20 and 90 °C every 10 °C. The latter measurements show that the heat capacity is independent of the density and the wood species. It increases linearly with temperature for all wood species
Creating a comprehensive framework for design, construction and management of healthy buildings
No full textInternational audienceWhile healthy buildings are investigated in academic research, practice, and policy, they often fail to address the needs and gaps due to insufficient knowledge transfer between them. Moreover, there is no general definition of healthy buildings that could act as a reference for different stakeholders of the building sector. Therefore, this paper presents a novel framework for healthy buildings and a definition for compiling existing knowledge and addressing the needs and gaps. The holistic approach of the framework was developed through an extensive literature review and tested with 12 building case studies in the major European climate zones. The framework outlines five different dimensions (improving mental and physical health, designed for human needs, sustainably built and managed, resilient and adaptive, empowering people), including 24 indicators and sub-indicators. The validation of the framework revealed that it is possible to assess different building projects against different indicators under each dimension. However, challenges remain due to issues such as lack of time, cost of data collection, or lack of documentation. The developed framework provides a balanced approach that promotes both individual well-being and broader sustainability goals. It provides necessary guidance to inform practitioners and policy makers as well as other building sector stakeholders to integrate healthy buildings thinking into their project development, assessment, and decision making
Impact of temperature on the dust/gas partitioning of semi-volatile organic compounds in indoor environments
No full textInternational audienc
Biocide and other semi-volatile organic compounds in settled indoor dust of CRESPI daycare centers and implication for public health
No full textInternational audienceThis study investigates the presence of biocides and other semi-volatile organic compounds (SVOCs) used in cleaning products in the settled dust of daycare centers and discuss their health impact through ingestion by young children. In Paris metropolitan area, 106 daycares area were investigated between 2019‐2022. Fifteen substances were analyzed in settled indoor dust by gas chromatography-tandem mass spectrometry. Detection rates ranged from 5 to 100%. Galaxolide and benzophenone showed highest median concentration: respectively 884 ng/g and 819 ng/g. The daily intakes (DI) of each chemical through settled dust ingestion were estimated and compared to those from food, inhalation, and dermal contact reported in the literature. Daily intakes from settled dust for musks, triclosan, geraniol, benzophenone, 2-phenylphenol, bifenthrin, and 4-n-nonylphenol were lower than those reported in the literature for other countries. The proportion of dust ingestion to total DI was negligible, except for benzophenone (DI=34%) for children aged 3 to 11 months. The DIs were well below the respective toxicological reference values for isothiazolinones, 4-tert-butylphenol, chlorocresol, and diclosan.Our results suggest that exposure to these biocides and the other SVOCs, taken individually, by dust ingestion in daycares, is not a major public health concern. However, benzophenone, presumed carcinogen for humans, may require further investigation because of its presence in several daycares
Stock stratégique de l'État d'antiviraux contre la grippe (Avis et Rapports du HCSP)
No full textInternational audienceStock stratégique de l'État d'antiviraux contre la grippe (Avis et Rapports du HCSP)Serge AHO GLÉLÉ, François CARON, Christian CHIDIAC, Christine DEBEURET, Emmanuel DEBOST, Alban DHANANI, Eric GAFFET, Sabine HENRY, Bruno LINA, Philippe MINODIER, Henri PARTOUCHE, Emmanuel PIEDNOIR, Dominique PLOIN, Bruno POZZETTO, France ROBLOT, Nadia SAIDANI, Sylvie FLOREANI, Marc DURANDEditeur : Haut Conseil de la Santé Publique (53 pages)Date du Document : 31 Octobre 2024Date de mise en ligne : 21 Décembre 2024https://www.hcsp.fr/explore.cgi/avisrapportsdomaine?clefr=1410https://www.hcsp.fr/Explore.cgi/Telecharger?NomFichier=hcspa20241031_stocstradeltatdanticontlagrip.pdfLe Haut Conseil de la santé publique (HCSP) se prononce à la demande de la Direction générale de la santé sur l’opportunité du maintien de l’oseltamivir, antiviral actif sur les virus grippaux, dans les stocks stratégiques de l’État.Les experts du HCSP ont pris en compte : •l’efficacité de l’oseltamivir en situation pandémique ; •la cible de 30 % de population visée par les stocks stratégiques ; •le volume actuel du stock stratégique de l’État en antiviraux qui dépasse la cible pour 2024 et l’atteint en 2025 ; •le faible risque pandémique à court terme.Le HCSP recommande :•de poursuivre des engagements pluriannuels pour le stockage des antiviraux face à une pandémie grippale ;•de ne pas remettre en cause l’intérêt potentiel de l’Oseltamivir qui, malgré le développement de nouveaux antiviraux à visée antigrippale, devrait conserver une place de choix dans l’arsenal en traitement préventif et curatif de la grippe pandémique ; •d’adopter un moratoire pour des acquisitions nouvelles d’Oseltamivir, le stock de l’État étant suffisant pour couvrir 2025 dans le respect des délais de péremption actuellement en vigueur en France ;•de chercher à prolonger les durées de conservation du princeps (Tamiflu®) et du générique (Ebilfumin®) actuellement en stock selon un délai à définir par l’ANSM;•de lancer une réflexion pour de nouvelles dispositions réglementaires permettant de réorienter le stock stratégique de l’État vers d’autres structures en vue de son utilisation avant péremption et limiter sa destruction.Dans un avis en préparation le HCSP se prononcera sur l’intégration de nouvelles molécules actives sur les virus grippaux et sur le volume des antiviraux dans les stocks de l’État. Ce document apporte un complément à :•Utilisation des antiviraux en période de circulation du virus grippal A(H3N2) - Hiver 2011-2012 du 5 mars 2012•Utilisation des antiviraux en extra-hospitalier en période de grippe saisonnière du 9 novembre 2012•Grippe saisonnière. Recommandation de prescription des antiviraux du 12 novembre 2015•Prescription d’antiviraux et grippe saisonnière du 16 mars 2018Lire aussi dans les avis et rapports :•Utilisation des antiviraux en période de circulation du virus grippal A(H3N2) - Hiver 2011-2012 du 5 mars 2012•Utilisation des antiviraux en extra-hospitalier en période de grippe saisonnière du 9 novembre 2012•Grippe saisonnière. Recommandation de prescription des antiviraux du 12 novembre 2015•Prescription d’antiviraux et grippe saisonnière du 16 mars 2018Read in english:•Place of oseltamivir and antiviral influenza drugs in the State's strategic stockpile du 31 octobre 202
Projet LOB+HIE Low Béton / High Earth - Abaques d'aide à la conception - Performances acoustiques de parois en terre-chanvre
No full textLes travaux menés dans le cadre du projet LOB+HIE concernent :• La réalisation de mesures de l’affaiblissement acoustique, sur deux types de systèmes de cloisons en terre-chanvre (échelle paroi)• La caractérisation des paramètres (physiques) mécaniques et acoustiques des matériaux mis en œuvre (échelle matériau)• La comparaison des résultats expérimentaux avec des simulations numériques, pour évaluer la pertinence des simulations, recaler les paramètres physiques et comprendre les phénomènes mis en jeu (échelle paroi)• La conduite d’une étude paramétrique pour évaluer la variation de la performance acoustique en fonction des matériaux pouvant être utilisés (échelle paroi)• La production d’abaques d’aide à la conception, à destination des professionnels du bâtiment (échelle paroi)Sur la base d’une étude paramétrique, des abaques de conception sont proposés pour évaluer la performance acoustique (en termes de Rw+C) pour 4 types de parois à base de terre-chanvre
Désintriquer les lumières urbaines : comprendre et mesurer la pollution lumineuse
No full textInternational audienceA summary of a workshop given at the CSTB Grenoble for the 2024 UNESCO International Day of Light.Un résumé de l'atelier organisé par le CSTB de Grenoble à l'occasion de la journée internationale de la lumière 2024, un évènement UNESCO
A Review of Contemporary Issues with Temporal Light Modulation of Lighting Systems
No full textInternational audienceTemporal light modulation (TLM) is defined as a temporal change in luminous or color quantities of a light source, resulting from fluctuations of the power supply. Research studies published during the past decade helped define new metrics describing well-known visual effects of TLM such as flicker and the stroboscopic effect. Other visual artifacts induced by TLM such as the phantom array effect are still under investigation to better understand their occurrence and visibility, especially when viewing modern types of LED modules and power supplies, used for instance in automotive lighting and in color-tunable decorative or entertainment lighting. With the advent of solid-state lighting, high levels of temporal light modulation and new types of waveforms exhibited by some LED lamps and luminaires have generated concerns among users and regulators, thereby motivating the establishment of new research, metrics, and standards. Limits have been set in regulations to protect people from undesirable effects. Below these limits, TLM can be used as a useful optical signature to facilitate remote sensing measurements of lighting systems and their obtrusive light components by lock-in detection techniques