Risk Of Electric Shock Research Articles

Обеспечение безопасных условий труда при зимнем обогреве железобетонных конструкций

The high rate of housing construction in 2023 significantly affected the level of occupational electrical injuries due to poor weather conditions and working in the winter season. The risk of electric shock at a construction site crucially increases in winter as heating reinforced concrete structures is mandatory. The study aims to develop design solutions to ensure safe working conditions and electrical safety at a construction site during the heating of reinforced concrete structures in winter. Electrical heating is used for concreting structures when the outdoor air temperature is expected to drop below 5 °C and the minimum daily temperature below 0 °C. The method is applied to prevent the freezing of freshly laid concrete, which can cause the formation of ice films around the reinforcement and filler grains. The study developed design solutions to ensure safe working conditions and electrical safety at a construction site when heating reinforced concrete structures in the winter season. Schemes of safe allocation of electrodes and heating wires in reinforced concrete structures, safe conditions and parameters of the use of heating wires, and safe conditions of structures’ heating and stripping are established. The technology and arrangement of work on installing electrodes and laying heating wires is described, and basic requirements for electrical safety at a construction site when heating reinforced concrete structures in winter are established. During the jobs’ performance, the safety requirements stipulated in the Occupational safety rules must be met. When assembling electrical installations, cables, and wires, the provisions of the Rules for Electrical Installations must be followed, during their operation, the Rules for the Technical Operation of Electrical Installations of Consumers of Electric Energy are applied. Employees must be trained, instructed, and provided with personal protection equipment. The heating area must be equipped with protective fencing, alarms, and safety signs. Electric wires and equipment must be in an operable state, undamaged, and insulated.

Protecting Electrical Workers in Conducting Locations with Restricted Movements

Conducting Locations with Restricted Movements (CLRs) pose unique electrical hazards due to the extensive presence of grounded conductive materials with which a person is likely to come into contact and the restricted freedom of movement of workers within these spaces. Extended physical contact is not solely a result of spatial constraints. It could also be associated with the specific tasks that workers need to execute. An example of this is work conducted on a transmission tower. This paper investigates the electrical safety measures necessary to protect operators in such environments. By examining the role of body resistance and the impact of different current pathways, this author highlights the inadequacy of the conventional disconnection of supply fault protection measure in CLRs. The paper discusses protective strategies, including supplementary equipotential bonding, use of double or reinforced insulation, electrical separation, and extra-low voltage systems. These measures are critical in mitigating the risk of electric shock and ensuring safety of workers in CLRs.

Indirect Thermographic Measurement of the Temperature of a Transistor Die during Pulse Operation

This paper presents aspects related to the indirect thermographic measurement of a C2M0280120D transistor in pulse mode. The tested transistor was made on the basis of silicon carbide and is commonly used in many applications. During the research, the pulse frequency was varied from 1 kHz to 800 kHz. The transistor case temperature was measured using a Flir E50 thermographic camera and a Pt1000 sensor. The transistor die temperature was determined based on the voltage drop on the body diode and the known characteristics between the voltage drop on the diode and the temperature of the die. The research was carried out in accordance with the presented measuring standards and maintaining the described conditions. The differences between the transistor case temperature and the transistor die temperature were also determined based on simulation work performed in Solidworks 2020 SP05. For this purpose, a three-dimensional model of the C2M0280120D transistor was created and the materials used in this model were selected; the methodology for selecting the model parameters is discussed. The largest recorded difference between the case temperature and the junction temperature was 27.3 °C. The use of a thermographic camera allows the transistor’s temperature to be determined without the risk of electric shock. As a result, it will be possible to control the C2M0280120D transistor in such a way so as not to damage it and to optimally select its operating point.

Hazard Identification Using Task Risk Assessment Method and Bowtie Analysis (Case Study: PT. Varia Usaha Beton)

PT. Varia Usaha Beton is a subsidiary of PT. Semen Indonesia Beton, which produces various types of products. PT Varia Usaha Beton (BSP Purwokerto) has an open work area where there are potential hazards such as physical factors, chemical factors and ergonomic factors. The aim of this research is to identify hazards, assess risks and control risks in the production process of ready-mixed concrete so that workplace accidents can be minimized. The methods used in this research are task risk assessment and bowtie analysis. Based on the research results, it was found that 1 risk belonged to the low category, 27 risks belonged to the medium category, and 11 risks belonged to the high category. Based on the bow-tie method, the major risks are exposure to fly ash and cement dust, risk of diesel spills, and risk of electric shock. The main causes of workplace accidents are pipe leaks and improper diesel filling. The main risk effects of workplace accidents are worker injury, and fire. The bowtie analysis method determines that the risk of electric shock is due to a damaged cable and the existing protective barrier is intended to replace the damaged cable. This risk has consequences, namely injuries to workers.

Assessment of fault potential and touch voltage in the low-voltage distribution line system of the residential community

Considering the increasing risk of electric shock in old residential communities, this paper investigated fault potential and consequential human-body touch voltage in the low-voltage (LV) distribution network under typical line-fault conditions by numerical simulation with a circuit approach. Three protective grounding configurations of the LV distribution system were of concern, and the electric shock scenarios considering practical situations were introduced for assessment. It has been observed that the phase-to-ground fault potential of equipment increases when the fault location is closer to the faulty equipment itself and decreases when it moves further toward the circuit end. The equipment in a building is likely exposed to the dangerous phase-to-ground fault potential under the line fault. As for line-to-neutral short circuit and neutral-line-open fault, the fault potential distribution mainly depends on the specific grounding configurations. Bonding of non-exposed steelwork in the buried building foundation to the nearby grounded grid may not be recommended in the literature, but it could effectively mitigate the touch voltage in and around the building of concern in this paper. Note that this measure, together with the local equipotential bonding method inside a flat, can provide enhanced protection against electric shock even if the protective device fails to operate or is unavailable. Among three grounding configurations, the one with multiple grounding points of the neutral wires up to the entrance of a building leads to the least dangerous touch voltage cases.

Electromagnetic interference and the effect of low-voltage protective measures at electric vehicle charging stations

The nominal power of electric vehicle charging stations or charging parks is constantly increasing. Most of the users are ordinary persons and handle such equipment with a rated power of several 100 kW. Until now, equipment with such power ratings was only common in electrical operating facilities such as industrial plants where the users are at least instructed and protective measures are specified. If ordinary persons handle equipment with such power ratings in the field, the question arises as to whether the conventional safety goals are met in the event of an electrical fault. The consideration is: If the power increases so much, it can be assumed that the short-circuit power and thus the fault current increase and so does the risk of a dangerous electric shock. In this contribution, calculations of line-to-earth short-circuits on the low-voltage AC side of the three-phase system and their effects in typical configurations of charging stations are carried out. Considering the electromagnetic interference, the calculations provide the fault current and its distribution to determine the electrical potentials during the fault. From this, the (partial) fault voltages and active fault voltages are calculated. Based on the active fault voltage, the expected body impedance and consequently, the body current can be determined. With the body current and the break time of the protection device the risk of electric shock using international standards as guidelines is evaluated. As a result, recommendations for the planning, installation and safe operation of charging stations are given. It turns out that considering certain aspects like the conductor cross-sections or the electromagnetic interference, the risk of electric shock can be reduced to a conventional level. Periodic testing of the electrical system is necessary for safe and reliable operation. For example, follow-on faults due to unintended, improper use by ordinary persons can be prevented. Also, regular inspection of the electrical system is necessary for safe and reliable operation to prevent hazards due to aging or wear. However, it seems challenging to define an installation guideline that applies to all configurations as the boundary conditions vary depending on the type of system, installations in the area of interference and environmental influences.

The Dominant Factors of Occupational Accident Risk Potential in Jember Regency

<div><table cellspacing="0" cellpadding="0" align="left"><tbody><tr><td align="left" valign="top"><p><em>The construction industry sectors have a significant risk of work accidents, making it one of the industries with a relatively high level of risk. According to the ILO, in 2018, 2,78 million workers died each year due to work accidents (13,7%) and diseases due to occupation (86,3%). This study aims to analyze the risk of work accidents among informal housing construction workers in Jember Regency. This type of research is quantitative descriptive research. The research was conducted in housing that is under construction which is located in Sumbersari District, Patrang District, and Kaliwates District, Jember Regency. The population in this study involved informal construction workers in Jember Regency. The population in this study included an unlimited population because easily entered by anyone and as the characteristics of informal construction do not require special skills. The sampling technique used non-probability sampling techniques, the sample calculation used quota sampling. The number of samples used was 97 respondents. The Accidental Sampling technique was used to select the samples. Risk analysis was through the Delphi method. Based on the calculation of all the risks that exist, it is indicated that there are three hazard risks with priority status, which means that they require immediate treatment. The risk identified was the risk of falling at the roof work stage (CPE 211,22), the risk of electric shock during the electrical installation work stage (CPE 197,85), and the use of PPE during the roof work stage (CPE 184,75). There needs to be risk control concerning the hierarchy of hazard control.</em></p><p><em> </em></p></td></tr></tbody></table></div><strong><em>Keyword: </em></strong><em> <strong>Construction, informal, work accident</strong></em>

Proposed use of TinkerCad in primary school computer science classes to support Arduino programming

– Nowadays, there is a strong emphasis on practical teaching, on teaching with the possibility ofusing what has been learned in the home environment or in leisure activities. This also requires the use ofmodern educational methods and, above all, modern teaching aids. This includes the TinkerCadenvironment accessible via a web interface. It allows not only full-fledged simulation but also the creationof your own program whether with deeper programming knowledge or just basic. Its great advantage isthat it is freely accessible and without any large financial outlay spent on buying an Arduino board orother electronic components, it allows you to develop your own simpler and more complex projects.These can also be developed by pupils in teams, thus encouraging pupils to work collectively. Last butnot least, we can also mention that using the simulation environment does not risk damaging theequipment and there is no risk of electric shock. Many pupils are very lively and interested in manythings, and they can also accidentally damage equipment. In our work, we will focus on the design ofsuch a project, where the Arduino calculates the product and sum from the two variables loaded. This willteach students how to use Arduino, LCD display, serial port with the aim of course to promotealgorithmic thinking and increase interest in science among students. By managing all this withoutprogramming in a commonly used programming environment, it allows us to use this example in theupper primary school years, where pupils can use their existing knowledge creatively.

The design of inductive power transfer system for fish aquarium using class-E inverter and LCCL impedance matching

<p>Nowadays, the accessories in fish aquarium systems such as water pump, internal filter, and LED light are powered using cables. This will cause to safety issue such as tangled wire, and risk of electric shock. Therefore, this work aims to design a wireless power transfer system to power up the fish aquarium’ accessories wirelessly without require any physical connection between source and loads. To be more specific, inductive power transfer (IPT) is used instead of capacitive power transfer (CPT) due to high efficiency ability owned by IPT. Class-E inverter circuit is proposed in this paper to convert DC to AC at nearly 100% efficiency. The inverter provides a low switching loss which is important as the circuit operates at high frequency, 1 MHz operating frequency. Furthemore, LCCL impedance matching circuit is added into receiver part of the system to enhance the efficiency of overall circuit. The analyses were done based on the distance between the coils and the misalignment of the coils against the output power and efficiency. The developed prototype is supplied by 24 V DC and capable to deliver 5 W power. The overall efficiency of the prototype is 87.81%.</p>

Evaluating Critical Safety and Health Risks by Job Safety Analysis and Analytic Hierarchy Process in Industrial Printing

Background: Critical risks are one of the most important problems in industries, which have high costs for the industry. This study aimed to assess critical safety and health risks through job safety analysis and analytic hierarchy process in industrial printing. Materials and Methods: The present study was conducted as a descriptive and analytical in one of the printing industries in Iran, in 2020. Critical risks were collected by visiting and observing the job safety analysis checklist. Then, critical risk prioritization was performed by an analytic hierarchy process using Expert Choice software, version 11. Results: A total of 23 hazards were identified. Mechanical hazards (61%) and chemical hazards (9%) had the highest and lowest frequencies, respectively. The identified safety and health hazards included musculoskeletal disorders (MSDs) in the upper and lower back, respiratory and skin exposure to chemicals, the risk of electric shock, and mechanical hazards (hand entrapment, hand amputation, and falling objects). Conclusion: The highest priority of critical risk was related to MSDs of the upper and lower back. The next priority of critical risk was related to chemical agents, respiratory exposure to organic solvents, and dermal exposure to organic solvents.

Analysis of electrical grounding design of substation and lines

This work analyzed the electrical grounding design of substation and lines. Substations are a crucial component of the electrical power system, so it is important to have properly designed grounding systems to protect people working nearby earthed facilities from electric shock risk, protect equipment from breakdowns, and ensure steady operation of the entire electrical system. There is frequently a concern that earth faults can produce hazardous voltage gradients in the earth at the site of the fault when energy is produced remotely and there are no other return channels for earth faults except the earth itself (called ground potential rises). In other words, someone standing close to the fault runs the risk of getting an electrical shock due to two factors: first, a potentially dangerous potential difference between the earth and any metallic objects they may be touching; and second, a potentially dangerous voltage gradient between their feet and the ground. The goal of constructing a safe grounding system is to give fault currents the simplest and shortest path without going above equipment and operating restrictions and negatively compromising service continuity. This work proposes a suitable grounding system design for alternating current (A.C.) substations based on the relevant IEEE Standards and International best practices. The study outlines the detailed calculations required to arrive at the mesh, touch, and step potential values appropriate for a good grounding system model for the A.C. Electrical substation. The suggested design provides for the safe functioning of all substation facilities, the safety of substation staff, and greater system dependability.

Is it safe for patients with metal implants to have iontophoresis treatment?

Iontophoresis passes electrical charge through skin to deliver drugs or reduce excessive sweating. Treatments can be performed by patients at home following initial instruction. A limitation of the technique is that patients are not permitted to have metal implants. These are hypothesized to increase the risk of electric shock, cause localized heating and/or corrosion. To investigate whether metallic materials (titanium, stainless steel and copper) placed in the iontophoresis circuit would lead to an unfavourable outcome regarding corrosion or local heating of the metallic object. This was carried out using mass loss and temperature change experiments, together with atomic force microscopy for stainless steel, to assess any surface roughness changes. The investigations were carried out under accelerated conditions (70 V compared with standard use 20-30 V). No changes in mass or clinically significant changes in temperature of any of the metallic objects (or surface roughness for stainless steel) were observed. This study suggests that patients with these metallic implants can safely undergo iontophoresis treatment. Further work is needed to review the impact on metallic implants with repeated exposure to the iontophoresis system to represent real-world evidence.

Analytical Investigation of the Effects of Secondary Structural Members on the Structural Behaviors of Transmission Towers

High-voltage transmission towers consist of structures that are designed to avoid the risk of electric shock and prevent the risk of collapse. Hence, for efficiency, they are generally designed as high-rise towers. The main tower posts are the primary structural members that resist loads under various load conditions. Therefore, the contribution of the secondary members to securing the stiffness and strength of the main posts by reducing the effective buckling length is an important one. However, we lack detailed secondary member design criteria. In this study, we observed the structural effects of the horizontal members and braces on the torsional stiffness, elastic buckling strength, and load-carrying capacity of a transmission tower using various structural analysis methods, including linear elastic, eigenvalue, and geometric nonlinear and inelastic analyses, under governing load combinations. According to the analytical results, it is the brace spacing rather than the horizontal members that substantially affects the structural performance. Therefore, we can minimize the number of horizontal members if we erect sufficient brace members. If the brace spacing is wide, then the horizontal members should be erected to create K bracing, thereby enhancing the buckling resistance of the main posts.

The Risk Analysis of Electric Shock in Different Grounding Systems

The risk of human body electric shock has always been an important issue to be considered in the design of grounding systems. To protect the human body from the risk of electric shock and to facilitate the design of the grounding system. In this paper, we use the Partial-Element-Equivalent-Circuit (PEEC) method to give numerical simulations for a typical grounding system and electric power distribution system under fault conditions. The electric shock for a typical grounding system, i.g. TN system or TT system, under phase-to-earth or phase-to-neutral short-circuit faults is studied. It is found that the complicated grounding grid may have a low step voltage than a single electrode. The touch voltage under phase-to-earth or phase-to-neutral fault conditions is analyzed. The TT system generally has a higher touch voltage magnitude than the TN-C system.

Synthesis and dilute aqueous solution properties of cationic antistatic surfactant functionalized with hydroxyl and ether groups

Abstract Polyester fibers tend to generate and accumulate electrical charges under friction and induction. This significantly affects the production and use process and even poses the risk of electric shocks and fire. Quaternary ammonium salt surfactants with a positive charge can be adsorbed on negatively charged polyester fibers and have excellent antistatic properties. Therefore, we have synthesised a cationic antistatic surfactant functionalised with hydroxyl and ether groups: N-hexadecyl-N,N-dimethyl-N-butanoxy glycerol ether ammonium chloride (HDBGA). The structure was characterized by 1H NMR, FTIR and ESI/MS. The excellent properties of HDBGA in aqueous solution were investigated by measuring the Krafft point (TK), surface tension, conductivity, and steady-state fluorescence. Also antistatic tests were carried out. The results show that the TK of HDBGA is below 0 °C indicating that it can still be applied in cold water. The new quaternary ammonium compound could effectively decrease the surface tension of aqueous solution to 31.28 mN m−1, where the critical micelle concentration (CMC) at 298.15 K was 3.83 × 10−4 mol L−1. In addition, the static electricity and static half-life values of the polyester cloths treated with the HDBGA solutions were also measured, as well as the effects on the fabric properties. The product exhibited excellent antistatic properties and satisfactory wash resistance, and the fabric fibers were not damaged.

Organization of Laboratory Work on the Basis of an Elective Course in Physics

The article describes the purpose of organizing an elective physics course for students of the 10th grade of Secondary School. At the same time, it is determined that the need for specialized training begins with high school. After all, the issue of admission of graduates to higher education institutions, the correct choice of the future profession, the presence of interest in this profession is relevant. In this study, special attention was paid to specialties in the field of Electrical Engineering. On the basis of this, the school organized an elective course in the technical direction, which became the basis for calling it «applied electrodynamics». At the same time, the hours, deadlines, and goals of the elective course are determined and presented in the article. Based on the organized methodology, one sample of laboratory work is presented. In the presented sitting laboratory work, the tasks of determining the dependence of a person's electrical resistance on the frequency of the applied voltage and assessing the risk of electric shock are presented. Students get acquainted with the dependence of the total resistance of the human body and the current flowing through it on the frequency of the applied voltage. In the course of this work, students of the school study the two-phase touch of a person to an alternating current network, the touch of a person to one phase of a three-phase network with a grounded neutral and the currents passing through the human body when a person contacts one phase of a three-phase network with an isolated neutral.

Assessing the Perception of Risk and Safety Climate of the Employees of Andishmandan Jonoob Company in 2020

Introduction: Safety climate and risk perception are two very important factors in safety studies that by examining and analyzing them, appropriate results can be obtained from the safety status of employees. This descriptive cross-sectional study was conducted randomly in 2020 on 388 employees of different departments of Andishmandan Jonoob Company project in Ahvaz.
 Methods: The Nordic Safety Atmosphere Questionnaire (NOSACQ-50) was used to assess the safety climate, the Flynn risk perception questionnaire was used to assess the risk perception, and the Likert method was used to assess the safety climate and risk perception assessment. Before distributing the questionnaire to the employees, a short educational class was held by the researcher on how to complete the questionnaire, and after distributing the questionnaire, the employees took 45 min to complete the questionnaire, and then the questionnaires were collected. To analyze the data, SPPS 24 software was used and to determine the differences between the studied variables, one-way analysis of variance (One-Way ANOVA) was utilized.
 Findings: In this study, the mean weight and height of the subjects were 81.57±18.45 kg and 176.32±24.68 cm, respectively. Among the employees, 43.81% had a diploma, 37.37% aged 30 to 40 years, 76.03% had 1 to 10 years of work experience, and 80.67% were workers. The mean scores of different dimensions of safety climate based on age, work experience, and education level showed that the mean safety commitment of employees for age, work experience, and education level were 0.76, 0.98, and 0.76, respectively. In this study, 14 workplace risks were considered that the risk of electric shock, back pain, and repetitive movements by employees did not have a score of 1 (very low risk). The risks of hitting the hot surface and falling objects on the foot by the employees did not have a score of 5 (high risk).
 Conclusion: The results of the mean scores of employees based on the safety climate questionnaire in the studied dimensions showed that the safety climate among the employees of the studied service jobs is relatively weak. Therefore, in order to reduce the potential risks in service jobs and reduce accidents, safety and health issues should be trained with proper and codified planning, and the safety culture of employees should be increased with new methods and new technologies. Regarding the perception of risk, it can be concluded that some risks were not felt by employees and were not observed by individuals; therefore, employees gave a low score to these risks.

Energy Management System Based on Automatic Intelligent Controller for Grid Connected Commercial LOADS

This paper grants the strategy and model of the automation system developed for managing electrical power demand in the home. All types of commercial loads are controlled by smartphones via Bluetooth technology. It can be controlled overall power that can be turned ON/OFF or can also control individual loads that are connected with relay and Arduino by simply pressing a button on mobile phone. This paper uses the HC-05 Bluetooth module to receive and transmit data from mobile phones and to home appliances. It improves better communication and responses between mobile phones and the home appliances. The purpose of the research is also to manage household appliances in order to reduce the risk of electric shock and for the convenience of elderly and physically disabled individuals who can easily access and control home appliances while staying in one location and without the assistance of others. Our home automation system works smartly by improving the quality of life and giving comfort to consumers thereby reducing the energy demand.

Electrical safety in low-voltage DC microgrids with B-type residual current devices

Residual current devices (RCDs) are most popular devices used in low-voltage installations for protection against electric shock and fire. In cases of high risk of electric shock the application of RCDs is mandatory. Currently, the spread of local direct current (DC) microgrids is widely considered. This creates new challenges for protective systems, in particular those based on RCDs. The main purpose of the research is to test the operation of B-type RCDs by simulating the conditions that may occur in DC microgrids as well as assessment of the effectiveness of electrical safety with the use of such RCDs. The research has revealed that theoretically identical RCDs in terms of technical data can have different tripping properties, including no reaction to residual direct current, which poses a risk of electric shock. This signalizes the necessity of extension of the normative tests performed by manufacturers. The scope of these additional RCDs tests is indicated, from the point of view of the persons’ safety in DC microgrids.

Pengaruh Kelembaban Dan Kadar Garam Terhadap Nilai Pentanahan Tanah Orgosol

Grounding is a very important protection or safety system in electrical equipment, to drain excess current to ground, protect people from the risk of electric shock, and protect equipment from being damaged. A good grounding system has a ground resistance in the range of 0-5 ohms. Moisture and salt content are several factors that affect the holding value. The type of research used is laboratory research using orgosol soil types. Based on the research, the grounding value at 634 humidity is 14572.3 x 104, higher than 766 humidity at 4670.2 x 104 ohm. This shows that the higher the humidity, the lower the soil value obtained. Soil was obtained with a salt content of 2319.75 × 104 ohms when 50 g of salt content was added. This is in contrast to the fact that adding 150 g of salt reduces the resulting ground reading by 879 x 104. This indicates that the higher the salt content of the soil, the lower the grounding value