Showing 9 results for Moradi
Mansour Ziaei, Hamed Yarmohammadi, Meisam Moradi, Faramarz Gharagozlou,
Volume 1, Issue 3 (Journal of Ergonomics 2014)
Abstract
Introduction: Working with Visual Display Terminals (VDTs) can be associated with visual complaints particularly visual fatigue and symptoms including headache, disruption in continuing the work and ocular disorders. The objective of the present study was to determine the prevalence of visual fatigue and its related risk factors in computer users of Kermanshah University of Medical Sciences in 2013.
Materials and Methods: This descriptive-analytical study was achieved on 260 computer users. The data were collected by Visual Fatigue, demographic and job questionnaires. For data analysis, Spearman, Mann-Whitney and Kruskal-Wallis tests were used.
Results: The mean (SD) age of the users was 36.74 (7.74) and daily working time with VDTs was 5.85 (2.28) hours. Visual fatigue score was 2.99 (1.97), so that 32.3% of computer users had severe eye fatigue. Meanwhile, 45.4, 21.9, 32.7 and 46.2 percentage of users suffered severely from eye strain, visual impairment, eye-surface disorder and extra-ocular problems. Visual fatigue incidence and its compliments were significantly increased with increasing of age, work experience and daily working hours with computer (p<0.05). Visual fatigue was higher in users wearing glasses than those not wearing glasses (p<0.001) and was lower in monitor to window angle of 90º than two other monitor to window positions of 0º (p=0.041) and 180º (p=0.036).
Conclusion: The prevalence of visual fatigue among computer users was very high. Visual fatigue and its serious consequences can be prevented by applying the principles of ergonomics such as regular and short breaks, looking at distant objects, blinking regularly and reducing the direct and indirect glares.
M.saeed Moradi, Davood Afshari, Taher Hoseinzade, Kambiz Ahmadi,
Volume 2, Issue 2 (Journal of Ergonomics 2014)
Abstract
Background: Safety signs are considered as visual intermediates for message transmission and play a crucial role in reducing accidents particularly in petrochemical industries. These signs are effective as long as they are designed in compliance with ergonomic principles, human factors, and cognitive features. Therefore, the present study aimed to investigate the psychological effects of safety signs in transmitting message given their designing features in the petrochemical industry.
Materials and methods: This descriptive-cross-sectional study was carried out on 100 employees in Mahshahr Petrochemical Complex. A 2 partite questionnaire was used to collect data the first part for demographic information and the second part included designing features of signs (familiarity, objectivity, simplicity, meaningfulness, semantic proximity). The Pearson correlation test was used to identify the correlation coefficients between signs features and scores given by the participants.
Findings: Mean and standard deviation of the scores of the signs’ message perception were 60.73 and 4.36, respectively. Cognitive features of the signs included familiarity and semantic proximity with a mean of 49.15 and 66.78, respectively. The factors of work experience, age, and academic level had no significant effect on guessing the meaning of signs (p>0.05).
Conclusion: The results of this study showed that no significant relationship existed between cognitive features of the signs and transmission of the message and message transmission of safety signs is affected by other features than their design. Therefore, in order to improve individuals’ awareness about familiarity of employees with particular meaning of signs, ergonomic design of safety signs and proper training for perceiving their meaning are proposed.
Shirazeh Arghami, Maryam Moradi, Fatemeh Habibi,
Volume 3, Issue 3 (Journal of Ergonomics 2015)
Abstract
Background: Driver’s fatigue is a major factor contributing to the prevalence of road accidents. A vast number of city dwellers in most countries use public transport bus services to move around the city. Driver’s fatigue causes job burnout and affects the risk of a traffic accident injuring the public. Several methods have been used to date for evaluating mental fatigue however, using questionnaires tends to be a less time-consuming and more accessible technique. The present study was therefore conducted to develop a mental fatigue questionnaire for public transport bus drivers.
Materials and Methods: The study was conducted based on the criteria used for qualitative research. Semi-structured interviews were held with public transport bus drivers using probing questions and data were collected until their saturation so as to enable access to a direct description of mental fatigue by the bus drivers. Data saturation occurred with 30 interviews and sampling was then discontinued. The analysis of the interviews led to the extraction of the themes and an initial list of questionnaire items was then developed. The psychometric properties of the questionnaire were then evaluated through examining the content validity and internal consistency of the items. The content validity of the items was calculated using Lawshe’s table. A minimum CVR of 0.99 and a minimum CVI of 0.75 denoted an acceptable content validity for the items. To determine the internal consistency of the items, 200 bus drivers completed the final version of the questionnaire. The data obtained were then analyzed in SPSS-16 using Cronbach's alpha to measure the reliability of the questionnaire and considering an acceptance level of 0.7.
Results: The interviews conducted at the beginning of the study with 30 drivers led to the emergence of an initial list with 26 items. A total of 9 items with a CVR less than 0.99 were omitted from the list and 17 items with adequate simplicity, clarity and correlation between them and which had a minimum CVI of 0.75 were kept. The questionnaire had a Cronbach's alpha value of 0.87 and was therefore considered a reliable tool.
Conclusion: The questionnaire developed in this study has a good validity and reliability and can therefore be used to assess mental fatigue in public transport bus drivers.
Zahra Pirmoradi, Rostam Golmohammadi, Javad Faradmal, Majid Motamedzade,
Volume 5, Issue 4 (Journal of Ergonomics 2018)
Abstract
Background: Inadequate lighting in the workplace can cause unconventional changes in the posture of office workers. Poor ergonomic conditions in the office cause inappropriate postures during work and increase pressure on the musculoskeletal system which can cause some disorders in long-term. In this study, the relationship between work environment lighting with the prevalence and severity of musculoskeletal pain among office workers has been investigated.
Methods: In this study, the intensity of local illumination at work surface and at the perpendicular surface (perpendicular surface to the work surface and at the height of workers eye), and intensity of general lighting was measured based on the standard of The Illuminating Engineering Society (IES) using the SEKONIC, C-7000 SpectroMaster. Also, to assess the prevalence and severity of pain of musculoskeletal disorders, a Nordic Questionnaire and a Body map index were used respectively. To assess the office work strain, Rapid Office Strain Assessment techniques (ROSA) were used. Data were analyzed by SPSS 21.
Results: The results showed that the average intensity of general lighting, local lighting at work surface and at the perpendicular surface were 30.6%, 33.9%, and 38.4% respectively, which is lower than required illumination intensity of Occupational Exposure Limits (OEL). The neck and waist had the highest prevalence of the musculoskeletal disorders among the workers. The highest frequency percentage of scores in the ROSA method was the score 5 (41.7%) which had a significant correlation with illumination intensity.
Conclusion: Illumination intensity can be considered as one of the important factors affecting posture in administrative staff. Therefore, the improvement of illumination intensity can decrease the severity of musculoskeletal pain and improve the body postures of the staff and, consequently, increase their comfort.
Mohammad Ghofrani, Majid Motamedzade, Mohammad Reza Aghaie, Zahra Mohammad Moradi,
Volume 7, Issue 3 (Iranian Journal of Ergonomics 2019)
Abstract
Background and Objectives: The statics and actions of people during daily activities plays a major role in the physical and mental health and dynamics of the community. Given that humans deal with different things in a day, it is necessary that they are adapted to his features of body. The main goal of this study is to design and construct tables and ergonomic chairs for cartography, in accordance with the physical dimensions of students.
Methods: In this research, one of the most used educational furniture, namely cartographic table and chairs, has been studied. After examining the satisfaction of this furniture, for ergonomic review and design in accordance with anthropometric dimensions, physical features of 160 students of art and 40 students of a technical and vocational school were measured. Then data was analyzed by SPSS 18 software.
Results: According to the results, about 70 percent of the students did not feel comfortable with the features of former chair and table, except for the length of the thigh. There was no significant difference between the different educational foundations in the vocational schools and finally, with the help of tonality features, the drawing table and chair were designed which except for the height of the sitting space, in other indices, there was a 100% correlation with the dimensions of the student's body.
Conclusion: In this study, there was a lot of dissatisfaction among students due to the lack of matching these educational materials with their physical dimensions which has caused physical, mental and psychological damage and poor quality of education. At the end of the study, through ergonomic design, matters of satisfaction, sustainability and reduced production costs and also the reasons for students' dissatisfaction with the drawing table and chairs is presented.
Reza Shahidi, Rostam Golmohammadi, Zahra Pirmoradi Rizevandi, Azar Soltani, Nassrin Shirmohammadi Khoram, Reza Kazemi,
Volume 8, Issue 1 (Iranian Journal of Ergonomics 2020)
Abstract
Background and Aim: Undesirable lighting at work environment causes visual and non-visual effects on employers. The aim of this study was to compare the quantity and quality of combined and artificial lighting in daytime and its relationship with the indexes of mental performance.
Methods: This study was carried out at 65 rooms and on 81 employees randomly selected from different clusters. Measurement of lighting parameters was done using a spectrometer. To assess the cognitive function, the Pshycomotor Vigiliance Task (PVT) test and for the sake of visual comfort, alertness and sleep quality, the Conlone, KSS (Karolinska Sleepiness Scale) and PSQI (Pittsburgh Sleep Quality Index) questionnaires were used respectively.
Results: Most artificial sources used in the rooms included fluorescent lights in different shapes and colors. The average indexes of combined lighting was more than artificial lightings (P<0.001). Visual comfort was correlated with high color temperature (P=0.006, r = 0.315). The employees with natural lighting had less visually impairment. The sleep quality of the subjects was related to the type of work environment lighting (Chi2=0.59, P=0.44). Alertness of subjects exposed to high color temperature or natural light was better at 8 and 11 hours. The results of cognitive performance test showed no significant difference between different lighting conditions.
Conclusion: Using natural light or artificial lights with adequate illuminance and high correlated color temperature can increase the alertness and visual comfort to some extent and improve the sleep quality of day staff employers.
Tahmineh Moradi Tamadon, Fakhradin Ghasemi, Iraj Mohammadfam, Omid Kalatpour,
Volume 8, Issue 4 (Iranian Journal of Ergonomics 2021)
Abstract
Background and Objectives: Firefighting is a difficult and dangerous job. This job requires decision-making and speed in action in critical situations. Such conditions increase the probability of human error in the firefighting activities. Setting up fire operators as the first step of emergency response is associated with high criticality. The purpose of this study is identification and assessment of the risk of human error while setting up and operating fire operators.
Methods: This descriptive cross-sectional study was performed in 2019. Tasks related to the operation of industrial firefighting operators were studied and analyzed by Hierarchical Task Analysis. Then, human errors in the operation of fire operators were identified and analyzed using the systematic human error reduction and prediction approach (SHERPA). Finally, appropriate prevention solutions were proposed to reduce the risk of errors.
Results: A total of 480 errors were detected for 130 tasks as 49.58% of them were action errors, 39.17% check type, 10.42% communication and 0.83% were selective errors and no retried error was observed. According to the results of risk assessment, 8.33% of the errors were unacceptable, 24.17% were undesirable, and 48.33% were acceptable risks but needed to be revised and 19.17% were acceptable without the need for revision.
Conclusion: The process of operating fire operators can be associated with human errors and prevent successful firefighting operations. Therefore, these errors should be identified and controlled using appropriate methods.
Samira Barakat, Habibollah Dehghan, Hossein Ebrahimi, Behnam Moradi,
Volume 9, Issue 2 (Iranian Journal of Ergonomics 2021)
Abstract
Background & Objectives: Thermal sensation is not a direct sense of air temperature but is related to people's feelings, sensory experience and psychological phenomenon, which can affect their performance, productivity, attitude and sense of satisfaction. The aim of this study was to determine the subjective thermal sensation and its relationship with stress, anxiety, depression and students' cognitive function.
Methods: This study was descriptive-analytical and was performed on 167 male students of Isfahan University of Medical Sciences. Students' subjective thermal sensation was measured on a seven-point scale and ambient temperature and humidity were measured in each student's room. The DASS-42 questionnaire was used to measure stress and anxiety and the "Reaction Timer" device was used to measure the cognitive function. The collected data were analyzed by SPSS software version 20.
Results: Students' stress, anxiety and depression were 40%, 47.3% and 41.3%, respectively. The mean temperature of the dormitory was 20.326 ° C, the mean relative humidity was 56.78% and the subjective thermal sensation of 29.9% of the students were neutral from the ambient temperature. There was a significant relationship between students' subjective thermal sensation and stress, anxiety and mean diagnostic reaction time, color selection, sound selection, number of errors in the diagnostic section and sound selection.
Conclusion: Students' subjective sensation of ambient temperature was obtained as a very important and influential factor because in addition to affecting stress and anxiety, it also had a significant effect on their time of diagnostic reaction and selective.
Seyeydeh Hasti Sadati, Mehdi Asghari, Maedeh Moradi Farahani,
Volume 12, Issue 1 (Iranian Journal of Ergonomics 2024)
Abstract
Objectives: Awkward posture is a primary cause of musculoskeletal disorders (MSDs) in the dental profession due to the nature of dental activities. This study aimed to examine both observational and device-assisted posture assessment methods used to study dental professionals as well as the reported prevalence of MSDs among them.
Methods: A search was conducted in Scopus, PubMed, and Google Scholar databases for studies performed from 2000 to 2021 using specified keywords. In total, 31 out of the 541 articles found in the initial search were finally included in this study after the exclusion of ineligible articles, duplicates, conference presentations, systematic reviews, and letters to the editor.
Results: Based on the findings, the neck (58%), back and waist (54.9%), and shoulder and hand (29%) areas had the highest reported pain and disorder. Several posture evaluation methods, namely Rapid Upper Limb Assessment (19.4%), Rapid Entire Body Assessment (19.4%), Electromyography (EMG, 13.8%), and Quick Exposure Check (QEC, 8.3%), were the most frequently used methods among all 17 methods employed in the studies.
Conclusion: Among the observational methods, the QEC method was the most practical one as it considered the experiences of dentists and various dimensions of dental tasks. Moreover, the EMG method was the most suitable device-assisted method for the assessment of posture in dentists. The use of questionnaires in conjunction with evaluation methods appears to enhance the understanding and effectiveness of posture assessment.
