Search Results (124)

Mathematical modeling and computer visualization of hazardous zones of toxic substance cloud spread that occur during different accidents at industrial enterprises located near residential areas are in high demand to support the operational planning of evacuation measures and accident response. The possible chain-like nature of fires and explosions of containers with toxic substances inside increases the importance of predicting changes in hazardous zone parameters in real time. The objective of this study is to develop algorithms for the development of a mathematical model of a hazardous zone during an explosion and fire at an enterprise. The subject of this study is a software tool created for the visualization of hazardous substance emission zones in real time, superimposed onto a development map to determine potential damage to human health and for the operational planning of evacuation measures. The proposed model takes into account variables such as the air temperature, wind speed and direction, the mass of the substance at each explosion and fire site, etc. C# and Visual Studio 2022 languages and an SQL database were used to create a software tool for visualizing the hazardous area. The testing of the calculation model and software used for the visualization of the hazardous zones of toxic substance cloud spread are presented on the basis of explosion cases involving a railway tank containing ammonia and the combustion of polyvinyl chloride at a chemical industry enterprise. The results confirmed the operability of the software and the prospects of its use in regard to the mitigation of the consequences of human-made accidents. Full article

Chemical leakage accidents in chemical industrial parks pose significant threats to personnel safety, particularly during evacuation processes, where individual behavior and evacuation strategies have a considerable impact on overall efficiency. This study takes a leakage incident at an alkylation unit as a case study. First, ALOHA5.4.7 software was used to simulate the influence of meteorological conditions across different seasons on the dispersion range of toxic gases, thereby generating an annual comprehensive risk zone distribution map. Subsequently, different evacuation scenarios were constructed in Pathfinder2024.1.0605, with the integration of trigger mechanisms to simulate individual behaviors during evacuation, such as variations in risk perception and peer influence. Furthermore, this study expanded the conventional application scope of Pathfinder—typically limited to small-scale building evacuations—by successfully adapting it for large-scale evacuation simulations in chemical industrial parks. The feasibility of such simulations was thereby demonstrated, highlighting the software’s potential. According to the simulation results, exit configuration, shelter placement, and individual behavior modeling significantly affect the total evacuation time. This study provides both theoretical insights and practical guidance for emergency response planning in chemical industrial parks. Full article

Ensuring employee safety is a top priority for every enterprise, and it is especially critical in high-risk industries like coal mining. To achieve this goal, it is essential to focus efforts on identifying existing hazards and thoroughly assessing the associated risks. Accurate identification and detailed characterization of occupational hazards play a pivotal role in the occupational risk assessment process, providing the foundation for effective safety strategies. This article presents an analysis of the process of identifying occupational hazards in hard coal mining, based on applicable legal regulations and a review of the relevant literature. The analysis reveals, on the one hand, a diversity of approaches to hazard classification, and on the other, a limited use of the characteristic features of hazards in classification processes. The findings of this review form the basis for proposing a systematic classification of occupational hazards in hard coal mining, taking into account the specific features of hazards in relation to their sources and potential consequences. The proposed classification not only categorizes hazards but also describes the specifics of hazard sources, such as environmental conditions, machinery, chemicals, and human factors, as well as the possible outcomes of these hazards, including physical injury, health impacts, and even fatalities. The aim of this article is to present a proposed classification of occupational hazards in hard coal mining and to provide a detailed characterization of these hazards based on the description of their sources and potential consequences. The proposed approach, grounded in the identification of characteristic features of hazards, facilitates the effective selection of preventive measures that can be implemented to reduce risk and improve workplace safety. Due to the presence of the full spectrum of natural hazards in Polish hard coal mining, the analysis draws on available statistical data, focusing on those hazards that contribute most significantly to fatal accidents and serious injuries. In conclusion, the article emphasizes the importance of a structured and systematic approach to identifying and assessing occupational hazards in the coal mining industry. By drawing on legal and literature-based insights, it aims to contribute to the development of more effective safety practices that protect workers and minimize the occurrence of workplace accidents and illnesses. Full article

The exploration of the statistical characteristics and distribution patterns of workplace accidents can help to reveal the intrinsic features and general laws of safety issues, which is essential for forecasting and decision making in safe production. Here, we conduct the detailed analysis of the distribution characteristics between the fatality number and the frequency of workplace accidents based on the in-depth data mining of various industries. The results show that the distribution between the fatality number and the frequency of workplace accidents follows a power-law distribution. Moreover, the exponents of such power-law distributions in different industries exhibit significant industry dependence, with the characteristic values of the power-law exponents in the coal mining industry, the hazardous chemicals industry, the transportation industry, and the construction industry being 1.55, 2.16, 2.15, and 2.92, respectively. Meanwhile, the temporal variation in the power-law distribution exponent in each industry can be used for the short-term prediction and evaluation of safe production, which will inform the decision making of the safety management department. Last, but not the least, the results of this study provide the theoretical basis for Heinrich’s Law and confirm that a substantial reduction in the number of small-scale accidents can effectively help control the frequency of large-scale fatal accidents. Full article

This study analyzes the risks posed by high-temperature summer conditions to atmospheric storage tanks containing acrylic acid and proposes mitigation measures. Recent increases in heat waves and tropical nights have led to an increase in the temperatures of acrylic acid storage tanks. This temperature increase results in higher vapor pressure and promotes spontaneous polymerization, thereby increasing the risk of explosions in atmospheric storage tanks. Hazard and operability (HAZOP) analysis identified explosions due to pressure buildup as a major risk scenario. To mitigate this risk, a spray-tower system was introduced through a layer of protection analysis (LOPA), which effectively reduced the hazards associated with atmospheric storage tanks. Additionally, the removal of flame-arrester replacement operations not only achieves economic benefits, such as reduced replacement costs and labor time, but also enhances safety by eliminating worker exposure to hazardous chemicals. These findings have significant implications for improving safety at industrial sites and highlight the potential economic benefits of preventing chemical accidents. Full article

This paper analyzes the occupational risks associated with the activities of transporting and spreading bituminous emulsion, focusing on a specific technological process used in a company in Romania. This study aims to identify risk factors, systematically evaluate them, and propose preventive measures aimed at reducing occupational accidents and diseases. The main hazards identified include exposure to hazardous chemicals, mechanical risks generated by the equipment used, and ergonomic factors that may affect workers’ health. Given the specificity of the activity analyzed, there is currently a lack of relevant studies specifically addressing the occupational safety and health of this category of workers, which further highlights the novelty and importance of the present research. Based on the results obtained, recommendations are formulated for optimizing work conditions, including the use of appropriate protective equipment, improving operational procedures, and implementing effective technical and organizational measures. This study contributes to the development of a solid preventive framework in the field of transporting and applying bituminous emulsion, thus supporting the improvement of occupational safety and health in the road construction industry. The results obtained can be used to develop more effective policies in the field of occupational safety and to raise awareness among decision-makers about the need for proactive measures in preventing occupational risks. Full article

Chlorine gas and hydrogen chloride are highly reactive chemicals that pose a significant hazard to living organisms upon direct contact. Also, chlorine-containing gases are often by-products of industrial chemical synthesis and can be released into the air as a result of accidents. This can lead to great pollution of the environment. To remove toxic gases, various filter systems can be used. Filters based on carbon nanomaterials can be suitable for capturing gaseous chlorine-containing substances, preventing their spread into the air. In this work, the sorption activity of various carbon-based nanomaterials (graphene oxide, modified graphene oxide, reduced graphene oxide, multi-walled carbon nanotubes, carbon black) in relation to gaseous chlorine and hydrogen chloride was investigated for the first time. It has been shown that employed carbon nanomaterials have an excellent ability to remove chlorine and hydrogen chloride from the air, exceeding the performance of activated carbon. Modified graphene oxide with an increased surface area showed the highest sorption capacity of 73.1 mL HCl and 200.0 mL Cl₂ per gram of the sorbent, that is almost two and five times, respectively, higher than that of activated carbon. The results show that carbon nanomaterials could potentially be used for industrial filters and membrane fabrication. Full article

Aiming at the problems of complex calculation processes, insufficient risk data, and reliance on experts’ subjective judgments that exist in traditional probability analysis methods, this paper proposes a probability analysis method for hazardous chemical storage tank leakage accidents based on neural networks and fuzzy dynamic fault trees (Fuzzy DFT). This method combines fuzzy set theory (FST) and Bootstrap technology to accurately quantify the failure probabilities of basic events (BEs) and reduce the dependence on experts’ subjective judgments. Furthermore, an artificial neural network (ANN) model for tank failures is constructed. This model can accurately calculate the probability of tank leakage accidents by taking into account the dependency relationships among basic events. Finally, a long short-term memory (LSTM) network is utilized to analyze the dynamic evolution trend of the probability of storage tank accidents over time. In this paper, this method is applied to the case of the “11.28” Shenghua vinyl chloride leakage accident. The results show that the calculation results of this method are highly consistent with the actual situation of the accident, indicating that it is a scientific and effective method for analyzing the probability of hazardous chemical storage tank leakage accidents. Full article

Academic laboratories operate in diverse fields. However, they expose individuals to occupational risks. To ensure social and economic sustainability, organizations must assess these risks. Accident prevention reduces injuries and financial losses. This study aims to structure an occupational risk assessment process in a university chemical laboratory in Brazil using the fuzzy analytic hierarchy process (FAHP). The methodology consists of identifying risks and applying the FAHP with linguistic variables to evaluate and prioritize them. Fifteen hazard sources were identified. In the risk assessment phase, the “Chemical Risk” criterion was given the highest priority, accounting for 54%, followed by “Accident Risk” at 26%, “Physical Risk” at 13%, and “Ergonomic risk” at 7%. This study contributes to applying a novel scientific method that enables low-cost risk assessment, reducing the need for significant investments in technology or specialized consultancy services. Furthermore, the research suggests applying this technique to different economic sectors, broadening the applicability of FAHP in occupational risk assessment. Full article

The leakage of hazardous chemical gases in chemical plants can lead to severe consequences. Source term estimation (STE) algorithms are effective in locating the leak source. The layout of the sensor network significantly affects the performance of the STE algorithm, yet the underlying mechanism remains unclear. In this study, we first applied computational fluid dynamics (CFD) to simulate 160 hazardous chemical gas leakage scenarios under multi-directional wind conditions in two hypothetic scenes with a natural convection environment, creating an accident dataset. Subsequently, a mathematical model for sensor placement optimization was developed and applied to the dataset to generate a series of sensor layout solutions. Based on these layouts, 12,216 STE cases were calculated. By analyzing the error distribution of these cases, the relationship between sensor placement and STE performance was systematically investigated, and the most effective sensor layout optimization strategies were discussed. This study found that in scenarios with complex obstacles, increasing the average measured concentration of the sensor network can significantly reduce the errors in the STE algorithm. Full article

Leakage in oil and gas transportation pipelines is a critical issue that often leads to severe hazardous accidents at oil and gas chemical terminals, resulting in devastating consequences such as ocean environmental pollution, significant property damage, and personal injuries. To mitigate these risks, timely detection and precise localization of pipeline leaks are of paramount importance. This paper employs a distributed fiber optic sensing system to collect pipeline leakage signals and processes these signals using the traditional variational mode decomposition (VMD) algorithm. While traditional VMD methods require manual parameter setting, which can lead to suboptimal decomposition results if parameters are incorrectly chosen, our proposed method introduces an improved particle swarm optimization algorithm to automatically determine the optimal parameters. Furthermore, we integrate VMD with fuzzy dispersion entropy to effectively select and reconstruct intrinsic mode functions, significantly enhancing the denoising performance. Our results demonstrate that this approach can achieve a signal-to-noise ratio of up to 24.15 dB and reduce the mean square error to as low as 0.0027, showcasing its superior capability in noise reduction. Additionally, this paper proposes a novel threshold setting technique that addresses the limitations of traditional methods, which often rely on instantaneous values and are prone to false alarms. This innovative approach significantly reduces the false alarm rate in gas pipeline leakage detection, ensuring higher detection accuracy and reliability. The proposed method not only advances the technical capabilities of pipeline leakage monitoring but also offers strong practical applicability, making it a valuable tool for enhancing the safety and efficiency of oil and gas transportation systems. Full article

Chemical plants inherently handle and operate with a wide range of hazardous materials, making them more prone to accidents compared to other industrial sectors. Consequently, safety management in chemical plants tends to be systematically organized based on elements of process safety management (PSM) systems. In June 2023, South Korea’s Ministry of Employment and Labor released the Serious Injury and Fatality (SIF) report, which summarized 4432 major accident cases that occurred over six years (2016–2021), including 1834 cases in manufacturing and related industries and 2574 cases in construction. The report provided an overview of these accidents, their causes, and measures to prevent their recurrence, with a focus on fatalities and severe injuries associated with critical losses across different industries. This study examined 16 accident cases that occurred at PSM-regulated facilities, which are managed on the basis of a systematic safety framework established by regulatory requirements. Among these, particular attention was paid to an explosion accident in the organic catalyst packaging process at a facility with no prior accident history and exhibiting unique accident characteristics. A systemic root cause analysis was conducted using the barrier-based systemic cause analysis technique (BSCAT) and the system theoretic accident model and process (STAMP-CAST) methodologies. The systemic analysis highlighted the critical importance of clearly identifying materials or factors that may inadvertently mix during the process design or mass production phases and evaluating whether such interactions could lead to accidents during the hazard assessment stage. Beyond incorporating the risk mitigation measures identified in the process design and procedural development phases without omissions, it is essential to periodically conduct “worker-centered risk assessments”. These assessments help evaluate the potential for accidents resulting from human errors, such as workers’ non-compliance with established procedures, which is a key aspect of preventing chemical accidents. Although this study did not include an evaluation of the impacts of high pressures or high temperatures on workers near chemical accident sites—hence, no specific recommendations regarding safe working distances are made—the findings are expected to contribute to the development of preventive measures for chemical accidents in smaller-scale plants where workers directly manage and operate processes. Full article

To improve the accuracy of the risk evaluation results of hazardous chemical road transportation systems, an accident risk evaluation model based on the combined weight-cloud model is proposed to address the problems of ambiguity and randomness in the risk factors for hazardous chemical road transportation accidents. First, incorporating the risk factor identification results, the risk evaluation index system for hazardous chemical road transportation accidents is established. On the basis of determining the subjective and objective weights of the indices by using the analytic hierarchy process and entropy weight method, the comprehensive weights of the evaluation indices are calculated by the linear weighting method. Then, the weighting results are combined with the cloud model to calculate the risk level of the evaluation indices at all levels and to output the results in the form of a risk cloud diagram to visually determine the risk level of hazardous chemical road transportation. Finally, the model is applied to evaluate the accident risk in an example. The results demonstrate that the model is both practical and applicable in the evaluation of the risk of hazardous chemical road transportation accidents. The evaluation results can provide a valuable reference for hazardous chemical road transportation enterprises to prevent accidents. Full article

Chemical laboratories, as the cornerstone of scientific innovation, face inherent risks due to the nature of their operations. Hazards such as flammable, explosive, and corrosive chemicals, combined with high-pressure and high-temperature conditions, present significant safety challenges. Accidents not only jeopardize the health and safety of personnel but also risk equipment damage, environmental pollution, and broader societal impacts. Ensuring a safe laboratory environment demands a multifaceted approach involving all stakeholders. Institutional managers must establish and enforce comprehensive safety management systems, covering chemical storage, equipment handling, and waste disposal. Laboratory directors play a pivotal role in overseeing the implementation of these protocols, ensuring all members are well-trained and compliant. Laboratory personnel, as direct operators, must adhere to safety procedures, utilize protective equipment, and responsibly manage experimental waste. By fostering a culture of safety and collaboration, laboratories can effectively mitigate risks, safeguard research environments, and advance scientific progress without compromising well-being. Full article

Tank vehicles are highly prone to rollover accidents, especially on curved–slope combination sections, which can cause hazardous chemical spills, endangering the environment, public safety, and human health. Therefore, it is crucial to conduct research aimed at reducing the risk of such incidents. Method: The rollover risk of tank vehicles under various loading conditions while traveling on curved–slope combination sections was investigated using driver–vehicle–road dynamics simulation. A multiple linear regression model was then developed to further quantify the impact of key factors on the rollover risk. Results: The results revealed that the road curve radius, vehicle operating speed, and liquid cargo fill level have the greatest impact on a tank vehicle’s rollover risk, and higher fill levels, higher speeds, and steeper downhill slopes all amplify the impact of curve radius on the rollover risk. In some cases, adhering to the road’s speed limit alone was insufficient to ensure the safe passage of the tank vehicle through curves. Conclusions: This study introduced, for the first time, a rollover risk assessment model for tank vehicles operating on curved–slope combination sections. The findings reveal effective methods to improve the transportation safety of tank vehicles. Practical Applications: The findings of this study can assist transportation agencies in selecting routes with lower rollover risks for tank vehicles with different configurations, as well as guide the development of loading standards and curve speed limits. This will effectively reduce rollover accidents of tank vehicles and support sustainable, safer transportation practices. Full article