Safety Code Research Articles

Parametric Analysis of the Compact and Long-Term-Operable Passive Residual Heat Removal System

Differing from land-based systems, conventional passive residual heat removal systems (PRHRSs) in nuclear-powered ships encounter challenges for use as safety systems due to limited space and difficulties in adopting safety aids. To resolve this problem, the authors have previously suggested a compact and long-term-operable PRHRS that uses air cooling and seawater cooling in tandem, and its feasibility was confirmed through a design study and transient analysis. Nevertheless, the system performance depends on various parameters, and their sensitivities have yet to be analyzed. The purpose of the current study is to conduct a parametric analysis of the system focusing on four parameters: filling ratio, thermal center difference between heat source and sink, heeling angle, and heat source temperature. The Multi-dimensional Analysis of Reactor Safety (MARS-KS) code was used for the parametric analysis. The results show that the parameters are highly interrelated with each other, and consequently, the system exhibits significantly different behavior depending on the parameter conditions. In particular, the filling ratio determines the overall trends of the system. It was also found that the presence of two heat sinks with a single heat source in the natural circulation loop of the system complicate the natural circulation behavior. Based on the results, we conclude that a thorough examination and careful control of the parameters are necessary to implement the proposed system. The highlights are as follows: 1. Parametric analysis of compact and long-term-operable PRHRS is conducted. 2. Analysis reveals that the filling ratio is the most dominant parameter for system performance. 3. The unique behavior of the natural circulation loop with two heat sinks and a single heat source is analyzed.

The National Electrical Safety Code, powerline clearances, and wildfires

AbstractThe provisions of the National Electrical Safety Code (NESC) have a long, but undocumented history. They are the primary means by which Public Utilities Commission agencies in various States in the United States enforce requirements for electrical clearances pertinent to high‐voltage powerlines. Examination of the NESC provisions for clearances between grounded guy wires and distribution phase conductors in the context of the Woolsey Fire indicates a comprehensive lack of realism in the Code provisions. While they may be entirely sufficient to prevent sparkover under normal operating conditions, they are wholly insufficient to cope with even modest adverse events. The profession should consider explicitly assessing factors beyond sparkover that affect the adequacy of clearance requirements. The provisions of the NESC (and California's parallel General Order No. 95) should be systematically reexamined in order to ensure that safety regulations can cope with adverse events that are serious, but not extreme. Since the vast majority of the electrical power network is aging and not new construction, a scheme should be developed to establish priorities for upgrading existing facilities at the highest risk of failure.

A new fire damage index to assess the vulnerability of immovable cultural heritage

The recurrent occurrence of devastating fires in cultural heritage constructions highlights the need for more studies focusing on the assessment of their fire vulnerability to support the development of adequate mitigation measures. To address the limitations of existing methods, this article introduces the Potential Fire Damage Index (PFDI) as a new approach. The PFDI is an indicator-based method that integrates twenty-one Fire Vulnerability Indicators (FVIs) into four categories with varying weights. The method is applicable to various types of heritage constructions and independent of national fire safety codes, which makes it a versatile tool for assessing fire vulnerability and estimating potential damage that can impact the cultural values of these structures. The article emphasizes the significance of the PFDI for preliminary identification of critical points in heritage constructions requiring vulnerability reduction measures, paving the way for subsequent more rigorous fire safety engineering analyses. The detailed criteria for assessing the FVIs are presented, and a case study illustrates the PFDI's applicability. The case study analyses a historic church in Portugal and evaluates its current conditions, as well as the impact of implementing certain measures to reduce fire vulnerability. To evaluate the robustness of the PFDI, its results were also compared with those of a well-established method in the literature.

Pengaruh Media Trainer terhadap Hasil Belajar Praktek Instalasi Listrik Komersil Mahasiswa Pendidikan Teknik Elektro

Electrical installation learning is the process of understanding how to install, maintain, and repair electrical systems. This includes an understanding of basic electrical principles, safety codes and standards, and best practices in the installation and maintenance of electrical equipment. This study aims to evaluate the effect of using media trainers in practical learning of commercial electrical. Installations on the learning outcomes of electrical engineering education students. The research method used was a quasi-experiment with a nonequivalent design. The samples for this research were two groups of students, each consisting of 10 people. One group received learning using trainer media, while the control group received conventional learning. Learning outcome data is collected through a final test which includes cognitive, affective and psychomotor aspects. The results of data analysis show that the use of media trainers significantly improves student learning outcomes in all aspects measured compared to conventional learning. The implication of these findings is the importance of using technology in supporting practical learning in the context of electrical engineering education.

Enhancement of Reflood Test Prediction by Integrating Machine Learning and Data Assimilation Technique

Data assimilation (DA) was revealed as a highly efficient approach to enhance the prediction’s accuracy, demonstrating the reliability of the simulation through uncertainty quantification analysis. However, in the numerical simulations, most of the tasks are highly nonlinear relationships between the parameters that directly affect the efficiency of the DA such as the large search space dimension, resulting in significant computational costs. This limitation can be overcome by implementing machine learning (ML) predictions that can efficiently expand the DA search space. Therefore, this study is aimed at enhancing the performance of DA by integrating ML and DA (IMD), proposing a new method to overcome the stand-alone DA limitations. The approach involved implementing a stand-alone DA using the multidimensional analysis of reactor safety (MARS) code to enhance the prediction of reflood tests. The output datasets obtained from the stand-alone DA were then used to train the deep neural networks (DNNs), and the accuracy of the DNN’s prediction was thoroughly evaluated with varying dataset sizes. This DNN subsequently can predict the enormous unobserved samples, enabling the identification and investigation of the prospective candidates for the subsequent DA process. The results demonstrated that the stand-alone DA achieved an accuracy enhancement of up to 41.3% in reflood test predictions, while the IMD yielded even more significant improvements, with a performance enhancement of 47.0%. These findings reveal that the IMD approach outperformed the stand-alone DA approach, particularly in the case of high flooding rate tests. In this context, the proposed integrating system can effectively overcome the high computational cost and enhance the performance of stand-alone DA.

«Безопасность» или «охрана» труда как основа построения законодательства о защите жизни и здоровья работников

A comparative analysis of the categories “labor safety” and “labor protection” as a fundamental basis for the formation of labor law norms is carried out. The International Labor Organization considers the concept of “safety and health at work” a priority. In Russia, labor law was formed using the basic concept of “labor protection”. The Labor Code of the Russian Federation understands labor safety too narrowly — only as the protection of persons working in special conditions. The proposals of scientists to replace the concept of “labor protection” with “labor safety” in the norms of the Labor Code of the Russian Federation are recognized as erroneous. In the interests of expanding the boundaries of protecting the rights of workers, it is proposed to legally recognize safety and labor protection as coinciding concepts and build the regulation of labor relations on this basis.

The Impact of Change Orders Caused by Legislative Changes on Program Management in the UAE Construction Industry

Program management is an important strategy for organizing and managing multiple interdependent construction projects to achieve strategic goals. However, when change orders occur, they can have a serious impact on the quality, time, cost of projects and, ultimately, affect the construction program. Furthermore, when change orders are caused particularly by legislative changes, such as environmental laws, taxes, tolls, safety codes, transportation, design or building codes, their impacts are unavoidable, yet can be managed through mitigation strategies. The existing literature only reports the implications of change orders on the project level and reports legislative changes as one of the contributing factors to change orders, but does not consider the implications on a program level. This study aims to close this knowledge gap by assessing the implications of change orders caused by legislative changes on program management in the construction industry during the construction phase, and explore what the possible mitigation strategies to manage change orders caused by legislative changes are. The objectives of the study include identifying the implications of change orders on construction projects in the UAE through a literature review using peer-reviewed journals and reliable industry sources. Additionally, we investigate the implications of change orders caused by legislative changes on construction programs through interviewing subject matter experts, evaluating the importance of the reported impacts, with possible mitigation strategies, through a structured questionnaire and Relative Importance Index (RII) and, finally, proposing a set of recommendations for key industry stakeholders. A mixed methods approach is adopted in this qualitative study, and the participants include clients, contractors and consultants from the construction industry, with a defined scope covering the construction stage only. The outcomes of the study can guide program managers, decision-makers and practitioners in the construction industry to successfully deliver all projects by directing proper resources to accommodate legislative changes.

Assessment of Indoor Air Quality Performance in a Building at Kemaman, Terengganu

Violations of IAQ regulations can lead to sick building syndrome (SBS), which manifests as symptoms like respiratory difficulties, eye irritation, skin issues, and headaches. Monitoring IAQ is crucial for ensuring the well-being of occupants and preventing health issues and reduced productivity. Compliance with IAQ regulations is necessary to avoid legal concerns and penalties. The study aims to evaluates IAQ in accordance with the Department of Occupational Safety and Health (DOSH) Malaysia's Industry Code of Practice on Indoor Air Quality (ICOP 2010), which provides guidelines and acceptable limits for physical and chemical contaminants on the impact on occupants' health and comfort in Bangunan Persekutuan Kemaman, a government office building in Terengganu, Malaysia. Objective and subjective measurements were collected to assess physical parameters, chemical contaminants, and ventilation performance indicators. The data revealed that the airflow, relative humidity, and light intensity in the building did not meet the ICOP 2010 standards, indicating the need for repair and maintenance of the mechanical ventilation and air-conditioning (MVAC) system. The subjective survey completed by occupants indicated symptoms such as drowsiness, fatigue, and headaches, which are associated with poor IAQ. The study concludes that improvements are necessary to ensure compliance with IAQ regulations and recommends further research on the relationship between air temperature, relative humidity, and older building designs.

A Terminological Study on the Legal Framework of Occupational Safety, Health and Working Conditions Code 2020

A Terminological Study on the Legal Framework of Occupational Safety, Health and Working Conditions Code 2020

Reproducible Benchmark for the SNAP 8 Experimental Reactor at Dry Conditions

This work provides fully reproducible benchmark models of the Systems for Nuclear Auxiliary Power (SNAP) 8 Experimental Reactor. Validation benchmarks of the criticality configuration experiments under dry conditions with no coolant are presented. In addition, relevant reactivity worth experiments, and measurement of power distributions are validated and presented here. Discrepancies between modeled and experimental results are at most 110 pcm for fuel and poison worths, and critical configurations that do not manipulate control elements are within 50 pcm. Larger discrepancies found in reflector element worth experiments are due to experimental methodology which was noted as being simplified due to limited calculational capabilities at the time, while discrepancy in the control element manipulated critical configuration is due the absence of structural components for modeling simplification. Power distributions closely follow what was observed in experiment with expected peaking in reflecting elements. All models are well documented with cited references describing and justifying assumptions, simplifications, and adjustments to reproduce the models with any nuclear safety codes; model inputs and outputs are stored in the snapReactors GitHub repository.

First implementation of quality control procedures on selected X-ray machines in South of Benin

Abstract Introduction: The use of X-ray equipment for medical diagnostic radiography procedures has increased due to advances and complexity of radiological procedures. Achieving good image quality while keeping exposure of workers, public and patient exposure to an acceptable level has become a prerequisite for the radiology department in order to comply with best international practices. The aim of this study was to undertake quality control measurement of seven (7) diagnostic radiography equipment in the south of Benin, the first of its kind. Material and methods: Multifunction detector (Piranha) and beam alignment test tool were used to perform quality control tests on seven (7) X-ray units. The method used as well as the interpretation of the results was based on the American Association of Physicists in Medicine (AAPM), United States Food and Drug Administration (FDA), Healing Arts Radiation Protection (HARP), Institute of Physics and Engineering in Medicine (IPEM), International Atomic Energy Agency (IAEA) and Canadian Safety code 35 (S.C 35) recommendations. Results: The quality control results showed that all X-ray equipment investigated were within standard limits for accuracy of exposure time below 10 ms; reproducibility of kVp, exposure time and dose output; specific dose-kVp2 linearity; and specific dose-mAs linearity. Five (5) out of seven (7) diagnostic X-ray machines passed quality control tests such as X-ray beam alignment, exposure time above 10 ms and kVp accuracy. One (1) X-ray machine failed the quality control test of beam filtration at 70 kVp and above. Conclusions: The findings of this study have provided baseline data for other radiology departments to embark on similar QA/QC activities, and also explore options for optimization of patient dose. However, there is a need to extend the study to cover more diagnostic X-ray machines throughout the country. It is anticipated that this would ultimately assist in improving radiation protection and safety during medical diagnostic radiological procedures.

Song, wind, and mayhem: The Indiana State Fair stage collapse.

The study of planning and execution failures resulting in disastrous outcomes for public events often offers much value when preparing for similar future events. While not recent, the lessons learned from the Indiana State Fair stage collapse of 2011 remain especially pertinent, due to thorough technical and managerial forensic investigations and their rigorous examination during subsequent litigation about the fatal event. Continued concern about life safety and inconsistent building code enforcement and design guidance for publicly occupied temporary structures, eg, outdoor stages, recently drew recommended changes by the International Code Council for the 2024 edition of the International Building Code. Codification of technical lessons learned is seldom immediate. Even with checklists and written plans of action, the full context of managerial lessons learned can be forgotten, as people without first-hand experience of earlier disasters plan later events. Salient events of the past can reinforce valuable lessons for today's practitioners, even to produce building code changes. That is certainly so for the Indiana State Fair stage collapse of August 2011.

Nurse Manager’s Guide to Life Safety Code for Dialysis Facilities

Nurse Manager’s Guide to Life Safety Code for Dialysis Facilities

Machine Learning Applications and Uncertainty Quantification Analysis for Reflood Tests

The reflooding phase, a crucial recovery process after a loss of coolant accident (LOCA) in reactors, involves cooling overheated fuel rods with subcooled water. Its complex nature, notably in its flow regime and heat transfer, makes prediction challenging, resulting in high uncertainty and computation cost. In this study, we utilized the data assimilation (DA) technique to enhance the prediction of reflooding phenomena and subsequently deployed machine learning models to predict the accuracy of the safety and performance analysis code (SPACE) simulation. To generate the dataset for the machine learning model, we employed the sampling method for highly nonlinear system uncertainty analysis (STARU), providing a high-quality dataset for a complex problem such as a reflooding simulation. In this dataset, the physical models were assimilated under their selected uncertainty bands and utilized the effective sampling approach of STARU, generating the high-quality output and efficient enhancement of SPACE predictions. Consequently, the implemented machine learning model can be used to enhance model development and uncertainty quantification (UQ) analysis using the system code.

Proposal of Application of a Simple Analysis Code DYMOS for Accident Analyses of Molten Salt Reactors

The Molten Salt Reactor (MSR) possesses unique characteristics, including the circulation of liquid fuel salt in-core and ex-core, and the absence of cladding tubes of fuel rods. To perform safety analyses for accidents and transients, the selection of appropriate models is crucial. Proposed models vary from the coupling of a three-dimensional (3-D) nuclear reactor model and a detailed thermal/hydraulic (T/H) model to a simple point reactor model coupled with a lumped parameter model of the T/H system. The authors have been investigating the development of a simple and accurate model that can be utilized during the design stage and licensing evaluation, while also providing transparency, which means that models can be easily understandable by experts and reproduced in licensing evaluation. Given the distinctive features of the MSR, the peak heat flux or fuel cladding peak temperature is not a requirement. Instead, the most decisive parameter for safety evaluations is the fuel salt temperature in the fuel salt boundary. As demonstrated in this paper, the outlet of the MSR core consistently displays the highest temperature.Based on the afore-mentioned prospects for both nuclear and T/H systems, the authors have developed a simple safety and transient analysis code for MSR (DYMOS). The DYMOS code has been verified for MSRE experiments, as described in this paper. However, the previous verification was limited to small experimental MSRs, and there is a lack of verification for large reactor systems. This paper shows that the DYMOS code is applicable to these larger reactors. In other words, the main objective of this article is not to claim the originality of the model of DYMOS code, but to propose applicability of such simple code to large reactor systems.

Multistage safety code based on responsive CdS photonic crystal organohydrogel

In the realms of information storage and display, achieving heightened levels of complexity and security has always been paramount. This study presents a multi-responsive material based on CdS photonic crystals, harnessing the properties of CdS photonic crystals and responsive organohydrogels. We incorporated temperature-responsive monomer N-isopropyl acrylamide (NIPAM), AIE monomer (2-(4-vinylphenyl)ethene-1,1,2-triyl)tribenzene (TPEE), and photochromic unit 2,2-diphenyl-2H-naphtho [1,2-b] pyran-6-carbaldehyde (naphthopyran, Np) into the organohydrogel to prepare the responsive gel material. It was then combined with CdS photonic crystals to fabricate the multistage responsive CdS photonic crystal organohydrogel. This material is not only capable of tuning the structure color of the photonic crystals through temperature but also triggers the AIE effect of the gel upon reaching the phase transition temperature. Additionally, it can initiate the photochromic effect of the material upon exposure to ultraviolet (UV) light. These responsive behaviors underpin the multistage response nature of the material. Capitalizing on these multi-responsive traits, we designed an array of multistage responsive anti-counterfeiting patterns and multistage security codes. This approach not only elevates the density of multi-layered information storage but also fortifies the tamper-resistance of traditional coding systems. The multistage responsive material has a wide spectrum of potential applications, particularly in anti-counterfeiting, information display, and encrypted data transmission, offering fresh perspectives in the domain of information security.

REVIEW OF FIRE BRIGADE EXTINGUISHMENT MODELS AS PART OF A BUILDING FIRE RISK ASSESSMENT

This paper presents models of firefighting operations of fire brigades from the point of view ofassessing the fire risk of buildings. The following seven related standards can be distinguishedworldwide: International Fire Code (IFC), NFPA 5000: Building construction and safety code,International Fire Engineering Guidelines (IFEG), Fire Risk Evaluation and Cost AssessmentModel (FireCAM), Fire Evaluation and Risk Assessment system (FIERA), PD 7974-5:2014Application of Fire Safety Engineering Principles to the Design of Building; Part 5 Fire and RescueService Intervention as well as a Fire Brigade Intervention Model (FBIM). Given the editoriallimitation as to the amount of text only the last one of them, which was used to the greatestextent in the construction of own model, was discussed in detail. The others have been discussedonly in a general way. In the final part of the work, the existing models were evaluated as partof the discussion. On the basis of a critical review of literature and own research of the authors,a stochastic model of firefighting activities of fire brigades in Poland was developed, which will beone of vital elements of the Aamks software developed at the Fire Safety University for assessingthe fire risk of buildings. The description of this model along with the results of its operation andtheir discussion will be presented in the successive parts of the same series.

Cavity effects on spontaneous ignition of pressurized hydrogen jets

The release of pressurized hydrogen jets can lead to spontaneous ignition, which poses a major challenge to the safe utilization of hydrogen energy. Previous studies have primarily focused on the spontaneous ignition of pressurized hydrogen released into tubes. However, in real industrial scenarios, pressurized hydrogen is usually released into the atmosphere or a complex equipment environment. Therefore, the effect of obstacles on spontaneous ignition needs to be considered. In this study, the spontaneous ignition of sudden releases of pressurized hydrogen entering various cavity shapes was modeled using the standard k-ω turbulence model, the eddy dissipation concept (EDC) model and a detailed 21-step chemistry model. The effects of the cavities on the jet flow fields and the spontaneous ignition were analyzed for various cavity shapes and release pressures. For the pressures considered in this study, the cylindrical cavity did not lead to ignition. The highest hydrogen jet temperature occurred in the contact region due to the shock wave reflection, after which spontaneous ignition could not occur due to the flow divergence. The pressurized hydrogen entering hemispherical and conical cavities enhanced the hydrogen-air mixing which led to combustible regions and the formation of multidimensional shock waves, which significantly increased the spontaneous ignition probability. The cavities created a high-temperature region inside the cavity that experienced ignition but the flames did not spread out of the cavity. The conical cavity produced lower flame temperatures than the hemispherical cavity but prolonged the flame lifetime. Higher initial hydrogen release pressures resulted in more violent multidimensional shock wave interactions and higher contact surface temperatures, which lead to earlier ignition times but with little impact on the initial location of the spontaneous ignition. The results of this study provide a scientific foundation for hydrogen safety codes, safe equipment designs and the development of industry codes and standards.

Retrofitting Techniques of Columns: A Comprehensive Review of Methods and Materials

Column retrofitting is a critical aspect of structural maintenance and improvement. It ensures that existing structures remain safe, resilient, and adaptable to evolving needs, contributing to the longevity and sustainability of the built environment. It is essential to maintain or enhance the structural integrity of buildings and infrastructure, ensuring their continued safety, resilience, and functionality. In such cases, columns may not meet current safety codes, and it becomes essential to bring them up to contemporary standards and ensure compliance with building codes. The purpose of this paper is to provide a brief overview of the methods of retrofitting, like steel jacketing, wrapping, concrete jacketing and bracing. For these advanced methods materials used in retrofitting techniques and advanced methods for column retrofitting, as it addresses various challenges associated with existing structures. Key Words: Retrofitting, Steel Jacketing, CFRP Wrapping, concrete jacketing.

Sandstone mining and silicosis deaths in Rajasthan: a critical legal and policy analysis

PurposeThe extant literature underlines the inadequacies of legal and policy frameworks addressing the safety and health concerns of sandstone mineworkers in India. Notably, Rajasthan, a state renowned for its extractive industries, mirrors these concerns. Against this backdrop, this paper aims to critically evaluate the relevant legal and policy landscape, with an emphasis on the recent central statute: the Occupational Safety, Health and Working Conditions Code of 2020 (OSHWCC). Given that the Code subsumes the key legislation pertaining to the safety and health of mineworkers, an in-depth critical analysis is essential to forge suitable policy interventions to address continued gross violations of human rights.Design/methodology/approachThe critical analysis of legal and policy frameworks on silicosis in sandstone mineworkers is based on a comprehensive reading of existing literature. The literature includes relevant laws, case law, reports of the Rajasthan State Human Rights Commission and National Human Rights Commission, publicly available data and key scholarly contributions in the field.FindingsAlthough the OSHWCC has made some changes to the existing regulatory architecture of mines in India, it has failed to safeguard the safety and health of mineworkers. Notably, the vast majority of mines in India – constituting approximately 90%, which are informal, seasonal and small-scale – remain beyond the jurisdiction of this Code. In Rajasthan, there are specific policies on silicosis, but these policies are poorly implemented. There is a serious shortage of doctors to diagnose silicosis cases, leading to under-diagnosis. The compensation for silicosis victims is insufficient; the distribution mechanism is complex and often delayed.Research limitations/implicationsThe central and many state governments have not established the regulatory institutions envisaged under the OSHWCC 2020; therefore, the working of the regulatory institutions could not be critically examined.Originality/valueThe paper critically evaluates laws and policies pertaining to silicosis in sandstone mineworkers, with a special emphasis on the state of Rajasthan. It offers a comprehensive critique of the OSHWCC of 2020, which has not received much attention from previous studies.