Reducing arc flash Hazard/Risk Category (HRC) in mining shovels based on standard NFPA-70E

2013 ◽  
Author(s):  
Eduardo P. Wiechmann ◽  
Anibal S. Morales ◽  
Carlos I. Llanos ◽  
Rodrigo J. Zulueta ◽  
Pablo Aqueveque
Keyword(s):  
Risk Category ◽  
Hazard Risk ◽  
Arc Flash

Technical textiles for protection against Arc-flash fire: Savesplash®

2020 ◽  
pp. 67-78
Author(s):  
Nandan Kumar ◽  
Sainath Shrikant Pawaskar
Keyword(s):  
Attenuation Factor ◽  
Threshold Energy ◽  
Single Layer ◽  
Weather Conditions ◽  
Electric Arc ◽  
Risk Category ◽  
Technical Textiles ◽  
Flash Fire ◽  
Level 3 ◽  
Arc Flash

Flash fire caused by electric arc is different than that caused by flammable liquids/fumes or combustible dusts. A suitable protective clothing for protection against electric arc-flash must be designed as per Indian weather conditions. Currently available garments are manufactured using two or three layers of woven/nonwoven combinations to achieve higher Hazard Risk Category (HRC) rating (level 3 and above). However, they are heavy and not comfortable to the end users. Savesplash® is a single layer inherent flame-retardant knitted fabric. Its arc rating was determined using ASTM standards. It achieved arc thermal performance value (ATPV) of 41 cal/cm2, breakopen threshold energy (E_BT) of 42 cal/cm2 and heat attenuation factor (HAF) of 94% when tested as per ASTM F1959/F1959M-14 which translated into an arc rating of 41 cal/cm2. This is equivalent to HRC level 4 ratings as per National Fire Protection Association’s NFPA 70E standard (USA). Further, cut and sewn gloves (HM-100) developed using Savesplash® fabric reinforced with leather on palm area achieved ATPV of 63 cal/cm2 and HAF of 94.5% when tested as per ASTM F2675/F2675M-13.

scholarly journals The Possibilities to Reduce Arc Flash Exposure with Arc Fault Eliminators

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1927
Author(s):  
Karol Nowak ◽  
Jerzy Janiszewski ◽  
Grzegorz Dombek
Keyword(s):  
Electrode Material ◽  
Low Voltage ◽  
Short Circuit ◽  
Electric Arc ◽  
Risk Category ◽  
Sudden Increase ◽  
Technical Personnel ◽  
Test Circuit ◽  
Arc Flash ◽  
Flash Exposure

This paper presents a method to limit the arc energy and hence the hazard risk category value according to IEEE 1584 by using a system of two oppositely connected multi-sectional thyristor branches. A test circuit for testing the effectiveness of a thyristor arc eliminator was designed and constructed. Arc ignition inside electrical switchgear can be a source of danger for technical personnel. The arc energy calculated according to the algorithms in IEEE 1584 can be significantly reduced by using multi-sectional arc eliminator MSAE. For the actual measuring object, the calculation of the hazardous arc flash zone and the hazard category was carried out for the system not equipped with an arc eliminator, and then the same was performed in a system with an arc eliminator. In parallel, the pressure inside the closed polyvinyl chloride (PVC) electrical box enclosure was measured and then compared with the calculated pressures that could occur during an arc fault. It was found that a Multi-Sectional Arc Eliminator (MSAE) effectively protects devices supplied from low voltage networks against the effects of short circuit or arc fault, such as the sudden increase of gas pressure inside the switchboard, which may cause it to break, significantly reduce the loss of electrode material, limit the spread of hot electrode material outside the switchgear, and also significantly reduces the energy of the electric arc.

Variance in Natural Hazard Risk Perception in Coastal Areas

2017 ◽  
Vol 25 (3) ◽  
pp. 21-46 ◽  
Author(s):  
Hyungjun Park ◽  
Gyoungjun Ha ◽  
Dalbyul Lee ◽  
Juchul Jung
Keyword(s):  
Risk Perception ◽  
Natural Hazard ◽  
Coastal Areas ◽  
Hazard Risk

Model for assigning security objects to a specific risk category in the field of fire safety

2020 ◽  
Vol 90 ◽  
pp. 19-31
Author(s):  
D. V. Zobkov ◽  
◽  
A. A. Poroshin ◽  
A. A. Kondashov ◽  
◽  
...  
Keyword(s):  
Adverse Effects ◽  
Fire Safety ◽  
Economic Activity ◽  
Fire Hazard ◽  
Risk Category ◽  
Negative Consequences ◽  
Acceptable Risk ◽  
Individual Object ◽  
Safety Requirements ◽  
Risk Categories

Introduction. A mathematical model is presented for assigning protection objects to certain risk categories in the field of fire safety. The model is based on the concepts of the probability of adverse effects of fires causing harm (damage) of various extent and severity to the life or health of citizens, and the acceptable risk of harm (damage) from fires. Goals and objectives. The purpose of the study is to develop the procedure for assigning protection objects to a certain category of risk of harm (damage) based on estimates of the probability of fires with the corresponding severity consequences, to determine the acceptable level of risk of harm (damage) due to the fires, to calculate and develop numerical values of criteria for assigning objects of protection to the appropriate risk categories. Methods. The boundaries of the intervals corresponding to certain risk categories are determined by dividing the logarithmic scale of severity of adverse effects of fires into equal segments. Classification methods are used to assign objects of protection to a specific risk category. Results and discussion. Based on the level of severity of potential negative consequences of a fire, risk categories were determined for groups of protection objects that are homogeneous by type of economic activity and by functional fire hazard classes. The risk category for each individual object of protection is proposed to be determined using the so-called index of "identification of a controlled person" within a group of objects that are homogeneous by type of economic activity and class of functional fire hazard. Depending on the risk category, the periodicity of planned control and supervision measures in relation to the specific object of protection under consideration is determined, taking into account its socio-economic characteristics and the state of compliance with fire safety requirements by the controlled person. Conclusions. To develop criteria for classifying protection objects that are homogeneous in terms of economic activity and functional fire hazard classes, the probability of negative consequences of fires, that are causing harm (damage) of various extent and severity to the life or health of citizens, and the acceptable risk of causing harm (damage) as a result of fires, is used. The risk category for each individual object of protection is determined taking into account socio-economic characteristics of the object that affect the level of ensuring its fire safety, as well as the criteriaof integrity of the subordinate person that characterize the probability of non-compliance with mandatory fire safety requirements at the object of protection. Calculations are made and numerical values of criteria for assigning protection objects that are homogeneous in terms of economic activity and functional fire hazard classes to a certain category of risk are proposed. Key words: object of protection, probability of fire, acceptable level of risk, risk category, dangerous factor of fire, death and injury of people.

Hygienic characteristics of the cosmetologists' lifestyle

2020 ◽  
Vol 60 (12) ◽  
pp. 958-963
Author(s):  
Natalia I. Latyshevskaya ◽  
Tatyana L. Yatsyshena ◽  
Elena L. Shestopalova ◽  
Irina Yu. Krainova
Keyword(s):  
Physical Activity ◽  
Risk Factors ◽  
Information And Communication Technologies ◽  
Health Risks ◽  
Healthy Lifestyle ◽  
Personal Hygiene ◽  
Risk Category ◽  
Essential Components ◽  
Group A ◽  
Group B

Modern trends in the deterioration of health and the growth of non-communicable diseases among the adult working-age population, including medical workers, actualize the importance of a healthy lifestyle for maintaining health and professional longevity. There were almost no studies related to cosmetologists' experienced group as representatives of aesthetic medicine. There is no scientific evidence on behavioral risks of this group. It justifies the relevance of this study. The study aims to analyze the essential components of the cosmetologists' lifestyle depending on age and the argumentation of priority behavioral health risk factors for preventive and recreational work justification. Sixty women (practicing cosmetologists in Volgograd at the age of 28-39 years (group A) and 40-53 (group B)) took part in the study. Lifestyle assessment included a modified questionnaire. The questionnaire consists of 5 blocks (block 1 - nutrition; 2 - physical activity, including hardening and active rest; 3 - daily regimen; 4 - personal hygiene; 5 - bad habits). It allows the analysis of the adherence to a healthy lifestyle based on the provision of quantitative data. Statistical data processing was carried out using the Excel package. The authors identified the essential and statistically significant differences in the cosmetologists' lifestyle depending on age. The respondents of group B demonstrated hygienically rational indicators in all blocks of the lifestyle more often. They had a more formed adherence to a healthy lifestyle: 504 answers in the category "insignificant risk" of respondents in group B versus 354 in group A. Distribution of answers in the "high risk" category: 119 responses in group B and 185 in group A. The lifestyle of 46.7% of the respondents in group B refers to a healthy lifestyle. 3.3% of the group B respondents have an anxious lifestyle, 50% have health risks. 10% of Group A respondents' lifestyle refers to a healthy lifestyle. 13.3% of Group A respondents' lifestyle refers to an anxious lifestyle; 76.7% of this group have health risks. There was almost no complex hygienic research profession of medical cosmetologists. Cosmetologists of the older age group (40-53 years old) are more conscious of maintaining a hygienically rational lifestyle. The most significant defects among cosmetologists aged 28-39 years are low physical activity, nutritional defects, insufficient duration of night rest, and excessive use of information and communication technologies for rest, accompanied by manifestations of neurotization and signs of pronounced fatigue. The obtained results argue the need to develop and implement informational and educational measures to prevent risk behavior patterns, taking into account the age of cosmetologists and the priority of the identified behavioral risk factors.

Students’ and Applicants’ Social Perceptions of the Risks of Educational Environment at Higher Education Institution

2019 ◽  
Vol 28 (11) ◽  
pp. 56-67 ◽  
Author(s):  
A. V. Lyalyuk ◽  
O. R. Tuchina
Keyword(s):  
Higher Education ◽  
Education Institution ◽  
Well Being ◽  
Social Institution ◽  
Educational Environment ◽  
Expert Assessment ◽  
Risk Category ◽  
Subjective Well Being ◽  
Higher Education Institution ◽  
Investigation Methods

Educational system is the most important social institution, which provides the development of a personality and frames his/her worldview and the conception of subjective well-being. Despite the large number of studies on the issue of psychological and pedagogical security of educational environment, the sphere of higher education still remains underexplored. The available empiric material has not received sufficient methodological justification and conceptualization. This article aims to provide the conceptualization of the risk category as applied to the educational environment of a higher education institution, as well as empiric investigation of the risks within the educational environment as viewed by applicants and students.Materials and methods. 213 applicants and 547 students of the Kuban State Technological University took part in the survey. The following investigation methods were used: expert assessment, interview, questioning, content analysis, analysis of means method, cluster analysis and factor analysis.Investigation results. Comparative examination of the manifestation degree of risks within the educational environment as viewed by applicants and students of higher education institution showed significant differences in the assessment of risk by these groups of respondents. From the point of view of applicants, the main risks are connected with social and psychological aspects of the educational environment of a higher education institution, relations within student groups and interaction with teachers, as well as with the issues related to the educational management and leisure arrangement. As viewed by the students, the risks within the educational environment include external and social and psychological risk factors, motivating risks and risks arising from the learning process organization and management and the related issues. Applicants’ notion of the risks within the educational environment of a higher education institution was mainly influenced by information they received from media and by the opinion of their relatives and age mates.Consideration and conclusions. It was proved that the applicants’ idea of the risks within the educational environment of a higher education institution is determined by the opinion of people they know personally, however it changes during the process of studying in higher education institution and acquiring their own experience of being within the environment. The investigation results allow creating a model of psychological and pedagogical security within the educational environment of a higher education institution. This model makes it possible to forecast main risks of the educational environment, their development, and evolvement and find solution to them. 

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