Comparative study of selected indoor concentration from selective laser sintering process using virgin and recycled polyamide nylon (pa12)

Additive manufacturing (AM) stands out as one of the promising technologies that have huge potential towards manufacturing industry. The study on additive manufacturing impact on the environment and occupational exposure are attracting growing attention recently. However, most of the researcher focus on desktop and fused deposition modelling type and less attention given to the industrial type of AM. Usually, during the selective laser sintering process, recycle powder will be used again to reduce cost and waste. This article compares the PM 2.5, carbon dioxide (CO2) and total volatile organic compound (TVOC) concentration between virgin and recycles powder using polyamide-nylon (PA12) towards indoor concentration. Four phases of sampling involve during air sampling accordingly to the Industry Code of Practice on Indoor Air Quality 2010 by DOSH Malaysia. It was found that PM 2.5 and CO2 concentration are mainly generated during the pre-printing process. The recycle powder tended to appear higher compared to virgin powder in terms of PM 2.5, and CO2. The peak value of PM 2.5 is 1452 μg/m3 and CO2 is 1218 ppm are obtained during the pre-printing process during 8 hours of sampling. TVOC concentration from recycling powder is slightly higher during the post- printing phase where confirm the influence of the powder cake and PA12 temperature from the printing process. In summary, this work proves that elective laser sintering (SLS) machine operators are exposed to a significant amount of exposure during the SLS printing process. Mitigation strategies and personal protective equipment are suggested to reduce occupational exposure

Design of non destructive testing on composite material using parallel plate electrical capacitance tomography: a conceptual framework

In this paper, a conceptual framework for a non destructive testing to check defect on composite material using parallel plate electrical capacitance tomography is being proposed. At the early stage, the possibility of using this method is being simulated using Comsol Multiphysic software. The simulation process has shown promising results to make this concept works. When a dielectric material is placed between the parallel plates, the permittivity distribution can be observed. As the number of electrodes of the sensor are increased from 2 to 8 electrodes, the capacitance value increase from 2.0131e-11-2.3532e-14i F to 5.2474e-11-3.0756e-13i F. Furthermore, there are significant results when the size and the permittivity of the object are varies

Design Safety Considerations for Water Cooled Small Modular Reactors Incorporating Lessons Learned from the Fukushima Daiichi Accident

The global future deployment of advanced nuclear reactors for electricity generation depends primarily on the ability of nuclear industries, utilities and regulatory authorities to further enhance their reliability and economic competitiveness while satisfying stringent safety requirements. The IAEA has a project to help coordinate Member State efforts in the development and deployment of small and medium sized or small modular reactor (SMR) technology. This project aims simultaneously to facilitate SMR technology developers and potential SMR users, particularly States embarking on a nuclear power programme, in identifying key enabling technologies and enhancing capacity building by resolving issues relevant to deployment, including nuclear reactor safety. The objective of this publication is to explore common practices for Member States, which will be an essential resource for future development and deployment of SMR technology. The accident at the Fukushima Daiichi nuclear power plant was caused by an unprecedented combination of natural events: a strong earthquake, beyond th e design basis, followed by a series of tsunamis of heights exceeding the design basis tsunami considered in the flood analysis for the site. Consequently, all the operating nuclear power plants and advanced reactors under development, including SMRs, have been incorporating lessons learned from the accident to assure and enhance the performance of the engineered safety features in coping with such external events. In response to the Fukushima Daiichi accident, the IAEA established an Action Plan on Nuclear Safety. The preparation of this publication was carried out within the framework of the IAEA Action Plan on effectively utilizing research and development. The main objective of this publication is to present technology developers and user s with common considerations, approaches and measures for enhancing the defence in depth and operability of water cooled SMR design concepts to cope with extreme natural hazards. Indicative requirements to prevent such an accident from recurring are also provided for States planning to adopt water cooled SMR designs and technologies. The IAEA gratefully acknowledges the information on technology and safety aspects provided by SMR design organizations and information regarding technical requirements provided by several Member States. The IAEA officers responsible for this publication were M.H. Subki of the Division of Nuclear Power and M. Kim of the Division of Nuclear Installation Safety

Technology Roadmap for Small Modular Reactor Deployment

Given the increasing interest of Member States in the near term deployment of SMRs, the objective of this publication is to present several model technology roadmaps to Member States which can be adapted to their specific projects. These roadmaps are based on the best ideas generated during a series of international meetings on this topic. For nuclear newcomer countries, these roadmaps assume that a Member State has already developed, or is at least well along the way in developing, the infrastructure necessary to operate a nuclear power programme. Guidance provided here, describing good practices, represents expert opinion but does not constitute recommendations made on the basis of a consensus of Member States