韓国における産業建築物中のアスベスト含有物質と空気中アスベスト濃度

This study introduces case adaptive detection models for detecting asbestos-containing building materials employing short-wave infrared hyperspectral images. The models are optimized for indoor and outdoor conditions, which could be applied to asbestos detection in interior and exterior building materials. Samples were collected from the most probable types and forms of building materials for both asbestos-containing materials (ACMs) and non-asbestos-containing materials (non-ACMs) to represent real-world conditions, utilizing the largest and most diverse dataset to date (11 types, 4 directions, and 4 forms). X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses demonstrated that chrysotile was the main asbestos mineral in the most of ACMs, as evidenced by characteristic chrysotile diffraction peaks, fibrous serpentine morphology, and coincident Mg-Si elemental distributions. The spectral characteristics of building materials are manifested by mineral components for ACMs and non-ACMs, where asbestos absorption (Mg-OH) identifies ACMs. The indoor RF model identified critical absorption features at 2299-2350nm, 1923-1967nm, and 2366-2426nm, corresponding to Mg-OH, OH, and CO₃²⁻ absorptions, achieving 95.3% accuracy. The outdoor RF model incorporated additional Fe-OH and Al-OH bands, achieving 96.5% accuracy. Real-world validation at three asbestos abatement sites and one large-scale site demonstrated practical applicability including scalability and computational efficiency with overall accuracies of 92.1% for indoor and 92.5% for outdoor conditions. Comparative analysis with existing benchmark methodologies confirmed superior performance, with our models significantly outperforming previous approaches. The models successfully detected ACMs across various material conditions, scales and effectively verified complete removal post-abatement with high computational speed. This approach delivers immediate practical value for compliance verification and quality assurance in real-world abatement scenarios and large-scale surveys, providing objective documentation for regulatory compliance while substantially reducing costs compared to conventional destructive sampling methods.

When asbestos containing materials (ACM) must be removed from the building before demolition, additional greenhouse gas (GHG) emissions are generated. However, precedent studies have not considered the removal of ACM from the building. The present study aimed to develop a model for estimating GHG emissions created by the ACM removal processes, specifically the removal of asbestos cement slates (ACS). The second objective was to use the new model to predict the total GHG emission produced by ACM removal in the entire country of Korea. First, an input-equipment inventory was established for each step of the ACS removal process. Second, an energy consumption database for each equipment type was established. Third, the total GHG emission contributed by each step of the process was calculated. The GHG emissions generated from the 1,142,688 ACS-containing buildings in Korea was estimated to total 23,778 tonCO2eq to 132,141 tonCO2eq. This study was meaningful in that the emissions generated by ACS removal have not been studied before. Furthermore, the study deals with additional problems that can be triggered by the presence of asbestos in building materials. The method provided in this study is expected to contribute greatly to the calculation of GHG emissions caused by ACM worldwide.

Risk assessment of asbestos containing materials in a deteriorated dwelling area using four different methods

7 - Mineral fibre-based building materials and their health hazards

This report presents guidelines for the assessment and abatement of asbestoscontaining materials in buildings based on available information. Background information is given on the history and use of asbestos-containing products in buildings, and regulations pertaining to their use. Included are control mea- sures for buildings containing asbestos materials, procedures for determining condition of the materials, and abatement techniques for containment and removal. A summary is presented of recent guide specifications and standards developed by industry, government agencies, and a standards organization which are related to asbestos-containing materials in existing buildings. These documents include guidance for the control, assessment, and abatement of such materials.

IntroductionNearly 14 million homes were built possibly using asbestos-containing construction materials between 1950 and the mid-1980s. Certain types of asbestos were not banned until 1999. Although exposure to asbestos is...

For seeking out suitable means of thermal insulation system of building envelope in south China, this paper has conducted simulation analysis on respective energy consumption of the typical residential template in cold region and south China, when adopt exterior thermal insulation system or interior thermal insulation system. The study has shown that the exterior thermal insulation system is much better than the interior thermal insulation system in energy efficiency in the cold region, but there isn’t obvious difference between them in south China. And from the aspects of the climate’s influence on the insulation quality, the installation’s influence on the building facades and the construction practices, it is proved that the interior thermal insulation system is more suitable than the exterior thermal insulation system in south China.

Concern for the health risk of occupants in buildings containing asbestos fireproofing, acoustic materials or lagging, among other products, has led to several investigations of airborne asbestos concentrations in buildings and exposure assessments of occupants and maintenance personnel. The purpose of this paper is to summarize these results, to place in perspective exposure to occupants and maintenance personnel, and to estimate risks based on these exposures. Regulatory implications of these results are discussed. It is concluded that asbestos-in-air measurements carried out with the most appropriate methods in buildings with damaged or undamaged asbestos-containing materials consistently show extremely low concentrations comparable to those measured outdoors for fibers greater than 5 μm in length. Risks to occupants in such buildings are correspondingly very low. Potential exposures are higher to those performing building maintenance procedures that may disturb the asbestos-containing materials. Operations and maintenance procedures are effective in protecting maintenance personnel through engineering controls, work practices and personal protective devices, which are used to a greater or lesser extent depending on the specific activity.

The service life of many buildings and houses built using asbestos-containing materials is coming to an end and their demolition will lead to a great deal of asbestos-containing waste (ACW). Conventionally, the disposal of such waste is conducted by isolation under controlled landfill procedures; however problems with this method exist, such as the risk at the time of re-utilization of landfill sites and the depletion of lands to be reclaimed. Melting treatment is a promising technology that could be used to solve these problems; a thermal process involving temperatures exceeding the melting points of asbestos, it transforms them into non-hazardous minerals. This technology may be applicable not only for friable ACW but also for nonfriable ACW. We performed a demonstration test of melting treatment of nonfriable ACW using a gasification and melting furnace of the shaft furnace type, which is a typical method for high temperature melting. Detailed observation using transmission electron microscopy as well as general analyses verified that the same level of asbestos remained in the slag obtained by high temperature melting as that of the background soil. In addition, the asbestos concentration in the exhaust gas and the dust from the facility were at sufficiently low levels, and it was thus verified that the asbestos concentration in the atmosphere in the vicinity of the facility during the melting treatment was comparable to that of Japan’s background level reported by the Ministry of the Environment in 2007.

Spacecrafts to go to inner or outer planet need to increase the insulation performance and also to evaluate its thermal performance precisely in order to design spacecrafts effectively. Our goal is to develop a new insulation system for spacecrafts instead of the traditional Multi Layer Insulation (MLI). Due to its high heat resistance, light weight, and high resistance to space environments, the porous super insulation polyimide foams (PI-F) is expected to progressively advance the spacecraft thermal insulation technique. The PI-F is based on the polyimide resin. In order to design the new thermal insulation system with PI-F, it is essential to clarify the thermal performance with combined phenomena of conductive and radiative heat transfer in PI-F. Heat transfer of new insulation with polyimide foam is basically decreased by using low conductive material instead of decreasing the radiative heat transfer. New MLI with polyimide foams has been constructed and its insulation performance was evaluated. As a result, we confirmed its insulation performance will be better than that of traditional MLI.

Current medical delivery drones lack dedicated thermal insulation systems. While the lack of dedicated thermal insulation is acceptable for the short flights these drones currently operate, scaling up these operations will require a different system. This project's aim is to determine if other lightweight materials, like polyisocyanurate and polyurethane, could be used in lieu of polystyrene for a more robust thermal insulation system. To test, the drones were modeled as rectangular containers of the same thickness, blood products were modeled as saline solution, and the climate in Sub-Saharan Africa was modeled by a heated chamber at 40°C. Combinations of polystyrene, polyisocyanurate, and polyurethane were tested against a control of only polystyrene, which is the material used for the body of the drones today. Polyisocyanurate was shown to be the most effective at insulating heat without adding a noticeable amount of weight to the overall drone. Limitations to this experiment include the various parts of the drones that were modeled using easily sourced parts instead of the actual parts used on the drone.

At present, the new generation of aircraft is developing in the direction of high speed, long endurance, high mobility, and repeatability. Some studies have shown that the surface temperature of the radome can reach even 1800 °C as the flight speed of the aircraft increases. However, the antenna inside the radome cannot serve at this temperature. Consequently, a thermal insulation system with electromagnetic wave-transparent ability and high-temperature resistance is urgently needed to protect the antenna from working normally. An aerogel material is known as "solid smoke," with the lowest density currently. Because of its high porosity (>90%) and the characteristics of nanopore size, its application in the field of thermal insulation always draws the attention of researchers. In this work, a novel amorphous/nanocrystalline boron nitride (BN) nanobelt aerogel was synthesized successfully. The BN aerogel shows lightweight (18 mg/cm3), good thermal stability (1400 °C under an inert atmosphere and 750 °C under an air atmosphere), wideband wave-transparent performance (dielectric constant of 1.03 and dielectric loss of 0.016 at 4-18 GHz), and thermal insulation property (43 mW/(m·K) at room temperature and 73 mW/(m·K) at 600 °C). The BN aerogel is a suitable candidate as an electromagnetic wave-transparent thermal insulator and fire-resistant material. What is more, the structural stability of the BN aerogel is good (Young's modulus remains basically constant during the fatigue tests), and the energy loss coefficient (∼0.56) is high; it also has the potential to be a mechanical energy dissipative material. The study on the amorphous/nanocrystalline BN nanobelt aerogel provides a new idea for structure design and performance optimization of a high-temperature electromagnetic functional insulation material.

As asbestos-containing waste from building demolitions has to undergo special treatment prior to recycling or final disposal, the demolition of buildings and the sorting of waste materials are conducted after checking for asbestos content in the construction materials (according to ISO, EPA or JIS). However, as solid waste is usually a mixture, it is possible that asbestos-containing material (ACM) is present in construction and demolition waste (CDW) that is transported to an intermediate treatment facility for CDW. In addition, the presence of ACM in disaster waste cannot be avoided. Therefore, a rapid method for the determination of asbestos at an intermediate treatment facility for CDW is required. In this study, the separation efficiency and the sorting time of CDW particles by grouping by visual appearance (GVA) were determined. In the case that the separation efficiency by GVA in this study was equivalent to that by visual observation with a loupe (DVL) in a previous study, the reduction of sorting time by GVA was evaluated. Newton’s separation efficiency by GVA and recovery rate were equivalent to that by DVL for 5.1 cm2 observation. In this case, the sorting time by GVA was 1/7 of that by DVL. Therefore, sorting time could be shortened by GVA under the condition of equivalent separation efficiency. In order to reduce the sorting time per worker to less than 1 h/t, only CDWPs having particle size larger than 12 cm for GVA or 20 cm for DVL for 5.1 cm2 observation should be subjected to sorting. Aiming to avoid diffusion of asbestos-containing waste, the authors suggest that grouping by visual appearance as a primary sorting step is effective to reduce sorting time of CDW from disaster waste or unknown origin.

Energy Efficiency Analysis in Building Walls in Tropical Climate Using Thermal Insulation System

In the unfortunate event of a fire, within the context of the evolution of façade fires, with a specific focus on the utilization of polystyrene thermal insulation (external thermal insulation composite system façades—ETICS façades), this study delves into the investigation of fires ignited by containers containing plastic bottles. Through an examination of the fluctuating temperatures within the affected room and its adjacent areas, as well as an assessment of the fire’s impact on polystyrene thermal insulation, this paper underscores the significance of incorporating non-combustible barriers into the building’s thermal insulation system. The tests conducted revealed that the temperature inside the room reached a maximum of 1100 °C, subsequently decreasing to 800 °C at a height of 2.5 m and approximately 400 °C at a height of 5 m. For this research, two 1100-L containers of household waste were employed, each weighing 45.5 kg and possessing a gross calorific value of 46.97 MJ/kg, with 10.7 kg of PET bottles inside, characterized by a higher calorific value of 23.90 MJ/kg as the source of the fire. Heat release rate highest values were obtained between 11 and 17 min, with a maximum value of 4919 kW. Thus, even in the absence of specific legislation, this study emphasizes the imperative need to establish safety distances for the storage of household waste away from the building’s façade to mitigate the risk of fire propagation, particularly in relation to materials such as polystyrene thermal insulation. Furthermore, in certain situations, extensive fire experiments on a grand scale, like the one undertaken in this research, hold a crucial position in confirming numerical findings for global researchers. This process assures the reliability and real-world usefulness of fire safety studies through the experimental outcomes presented in this investigation.