Showing 13 results for Mououdi
Mohammad Amin Mououdi,
Volume 3, Issue 3 (Journal of Ergonomics 2015)
Abstract
Introduction: An important measure for ensuring safety in the operation of industrial machinery is to install proper guards that prevent machine hazards and protect operators. The design of industrial machine guards is a key issue in ergonomics and worker safety and has become a focus of research in hand anthropometry.
The present study was conducted to assess the different hand anthropometric dimensions of employees in an industrial unit and to design a fixed mesh guard in the shape of a rectangle for industrial machines and to use the collected data for the standardization of industrial machine guards in Iran to help prevent machine hazards.
Materials and methods: Thirteen right hand anthropometric dimensions of 97 male and female employees of an industrial unit were examined. To design a standard fixed guard, the length dimensions of the 99th percentile of men and the thickness (diameter) and width of the 1st percentile of women were calculated.
Results: According to the data obtained, a standard fixed guard creates a safe distance of 196.61 mm with the hazardous components of the machine, a gap length of 10.19 mm and a gap width of 8.29 mm. Comparison of 6 parameters, including DIP, PIP, MCP, TE, DPC and WR, with the OSHA regulations showed that PIP and WR had decreased, MCP, DIP and TE had increased and DPC could not be analyzed given the lack of sufficient information on the parameter in the OSHA.
Conclusion: The design of machine guards that help prevent industrial hazards is an integral part of workplace safety. The analysis of DIP, PIP, MCP, TE, DPC and WR in the present study and in a study conducted by Vaillancourt et al. showed some of the parameters to have increased and some to have decreased compared with the OSHA regulations. This study also reveals the need for revising ISIRI 11800, a standard published by the Institute of Standards and Industrial Research of Iran.
Mohammad Amin Mououdi, Seyed Noroddin Mousavinasab, Seyed Mohammad Reza Gramian, Jafar Akbari,
Volume 4, Issue 1 (Journal of Ergonomics 2016)
Abstract
Introduction: Introduction: Inappropriate sizes of school furniture and the deformation of children’s bodies is one of the issues of concern in the world. The aim of this study was the evaluation of anthropometry of primary students aged 6-12 years in Mazandaran, Iran and the design of school furniture based on the anthropometric criteria of the students.
Methods: In this cross-sectional study, 18 anthropometric dimensions of 2336 boys and girls aged 6-12 years in 2014-2015 were measured. To collect data, anthropometric chair, camera and camera stand, and Anthropometric photo graphical software were used. After determining the anthropometric dimensions, ergonomic school furniture was designed.
Results: Average, minimum, maximum, standard deviation, median and percentile value of 2.5 to 97.5 of the anthropometric dimensions of students were calculated. The results showed that gender had no effect on the popliteal height in the age groups of 6 to 7 and 7 to 8, but age had effects on popliteal height (P < 0.001). In the age groups of 8 to 9 and 9 to 10 years and also the age groups of 10 to 11 and 11 to 12 years both gender and age had effects on popliteal height (P < 0.001).
Conclusions: The results showed that by eliminating the effects of gender, 16.2 mm popliteal height increased per year. It was also found that after eliminating the effects of age, popliteal height increased 20.39 mm more in girls than in boys. Until the age of puberty, the anthropometric dimensions in girls increased more than in boys. The dimensions of ergonomics tables and chairs for students were designed in three sizes.
Fatemeh Baghipour Sarami, Ali Bozorgiamiri, Mohammad Amin Mououdi, Mohammad Taghipour,
Volume 4, Issue 1 (Journal of Ergonomics 2016)
Abstract
Introduction: Many employees in different professions including nurses work with shifts. On the other hand, different and long shift work can endanger physical and mental health of nurses. This study, according to ergonomic standards, aimed to design a model for shift working in order to minimize the problems caused by shift work.
Methods: In this study, all 35 nurses working in the emergency ward of Imam Sajjad (AS) Hospital of Ramsar city, Iran, were considered. Then, the information gathered from answering the Morningness-Eveningness questionnaire (MEQ) (Circadian rhythm) and Survey Sampling International (SSI) (personal and social charactristics) questionnaire were changed to a model and then reconstruct after comparing it again with circadian rhythm principals. The final model was implemented with GAMS (gamma-glutamylaminomethylsulfonic acid) and at the end, shift working with ergonomic criteria were proposed.
Results: Shift working were designed for each nurse. Also, the obtained objective function value (Z=1.110223e-16) showed that the designed model was really close to ideal model. According to hospital rules and policies, if five more nurses get added to the currently employed ones, the proposed working program on one hand will improve satisfaction and efficiency of nurses and on the other hand it can decrease the effects of disorders on shift work.
Conclusions: Hospitals can have healthy and motivated workforce by applying the scientific approach to adjust a suitable working plan for their nurses and decrease the number of disabilities and also the rate of early retirement.
Mohammad Amin Mououdi, Ismail Shokrolahi, Royan Shahpuri, Jamshid Yazdani-Charati,
Volume 5, Issue 2 (Journal of Ergonomics 2017)
Abstract
Introduction: In recent years, with the progressive development of various scientific, research and industrial fields, there are musculoskeletal disorders in computer and laptop users. Musculoskeletal disorders including pain and pressure in areas such as wrists, elbows, neck and shoulders, along with the fatigue of these areas, especially back and waist pain are common among many computer and laptop users. The aim of this study was to design a customizable ergonomic table for using laptops based on the anthropometric characteristics of students of Mazandaran University of Medical Sciences.
Methods: This study was conducted on 108 (61 males and 47 females) students of Mazandaran University of Medical Sciences. Ten parameters including knee height sitting on a chair, eyes- elbows height, cross-legged posture kneeling length, cross-legged posture kneeling height, thick thighs, elbow rest height-sitting, shoulder-fingertip length, abdominal depth, hip breath, and elbow-fingertip length were measured using the adjustable seating, caliper and meter. The SPSS software version 20 was used to analyze the data. Then, the percentiles 1 to 99 and the golden number 1.618 were used to design the table.
Results: The mean age of the subjects was 23 ± 3.14 years. Based on anthropometric characteristics, gold number, resulting percentiles and design equations, an adjustable ergonomic table was designed in three seated sitting, four-knee and Fowler’s positions.
Conclusions: It is expected that after putting this device on the laptop, the musculoskeletal disorders caused by its use will be reduced. Because of limited studies have been conducted in this area, it is suggested that further studies in this regard be undertaken in the future.
Mohammad Amin Mououdi, Mohsen Hosseini,
Volume 5, Issue 3 (Journal of Ergonomics-Fall 2017)
Abstract
Background: Sitting for long periods of time is a part of the illness, which can happen in the workplace and the lack of attention to the ergonomic principles causes musculoskeletal disorders such as backache, pelvic ache, shoulder ache, elbow ache, arm ache, wrist and ankle ache, and muscle aches in the other parts of the body. The present research was carried out according to the ergonomic principles and designs, in order to design an ergonomic chair, suitable for the computer users in the monitoring room of one of the industries in the Mazandaran province.
Methods: The participants in this study included a total of 32 male staff from the monitoring room of one of the industries in the Mazandaran province. A total of 24 anthropometric parameters were measured from the body of each of the subjects, sitting in a vertical position on an adjustable chair, using anthropometric calipers and meters and the data were analyzed with the Excel and the Minitab statistical programs.
Results: The mean age of the subjects was 42.59 ±5.34 years and the 5th, 25th, 50th, 75th, 90th, and 95th percentiles of their anthropometric dimensions and Pearson's correlation coefficients were obtained to design the height, the depth, the height, and the width of the ergonomic chair. All parts of the chair had two degrees of freedom. The neck and back supports, adjustable for this type of chair were designed specifically. Also, using MIT standards, the level of seat compressibility was measured to be 4.26 cm, based on the 95th percentile weight.
Conclusion: Considering that other countries design and produce suitable chairs, focusing on the anthropometric characteristics of the individuals, studies, similar to this research could be recommended in the different parts of the country, in order to design and produce appropriate chairs for the physical dimensions of the people and their needs.
Mohammad Amin Mououdi, Seyed Noroddin Mousavinasab,
Volume 5, Issue 4 (Journal of Ergonomics 2018)
Abstract
Background: Problems and complications caused by inappropriate tables and chairs dimensions in changing the shape of children's body are important issues nowadays. The aim of this study was to evaluate anthropometric dimensions of the changes in elementary school students of Mazandaran province between 1992 and 2014.
Methods: in two cross-sectional studies carried out between 1992 and 2014, anthropometric information of elementary school students were collected in the range of 6 to 11 years old. In 1992, 1758 students out of a population of 254204 and in 2014 2336 students out of a population of 208820 were selected using stratified random sampling method. In 1992, mechanical anthropometric was used for measuring while in 2014, an anthropometric chair photographic camera and anthropometric photogrammetric software (made by the researcher) were applied to measure. In this study, we measured the parameters of weight, amount of height, seat height, sitting height, shoulder width, hip width, thigh thickness, sitting length of the buttocks, hip length in sitting leg knee position. Data were analyzed using SPSS software package version 20.
Results: Comparison of the two study revealed that the average (SD) of the boy's weight increased from 25.82 kg (9.5) to 32.17 (11.03) (6.35 kg increase) and girls ‘weight accelerated 25.19 kg (6.5) to 33.10 (12.50) (7.91 kg increase). The boys' height was increased from 127.26 cm (9.6) to 134.80 (10.84) (54.7 cm increase) and a raise was observed form 126.5 cm (10.1) to 133.30 (11.18) (6.8 cm) among girls’ height and there were changes in other anthropometric factors as well.
Conclusion: The results show that students have significant anthropometric changes during a 22 years’ period, and it is needed to carefully design and construct children's devices especially the school chair and table.
Mohammad Amin Mououdi, Seyedeh Fatemeh Razzaghi Pahnehkolai, Fariba Qhaempanah, Amirhossein Mahdavi, Ahmad Reza Veisi,
Volume 8, Issue 2 (Iranian Journal of Ergonomics 2020)
Abstract
Background and Aim: Two toilets in sitting-type and squatting-type (Traditional) are currently used by Iranian People. Since each of these two types has its own disadvantages and merits, this research aims to design a squatting-type toilet based on ergonomic principles to eliminate its disadvantages.
Methods: 61 subjects (29 males and 32 females) aged 19-60 years were enrolled in this study. Seven anthropometric characteristics were measured using a tape measure with an accuracy of one millimeter in these subjects. A questionnaire containing 4 questions was given to them. Each person was squatting for 2 minutes on different slopes from 0 to 20 degrees. Assessment of Localized Postural Discomfort (LPD) by asking people at 3 points of body, at different slopes, and goniometry in the areas of (A), (B) ,(C) and (D) was also performed.
Results: Based on the anthropometric characteristics of the individuals, LPD and goniometry findings in different areas of the body and dimensions of toilet in the sole position, length 32.33 and width 12.74 cm was obtained. The angle between the soles of the feet was 23.33 degrees and the required slope of the soles was 12 degrees.
Conclusion: The findings of this study suggest that modification of the sole position in squatting-type toilet and its sloping design can be effective in making users comfortable. Given the small number of studies on this type of toilet, further studies in this area, including research on specific populations such as the disabled people, children, pregnant women, the elderly, etc., are necessary.
Hossein Manouchehri, Payam Moradpour, Mohammad Amin Mououdi, Ebrahim Aga-Rafiei,
Volume 8, Issue 3 (Iranian Journal of Ergonomics 2020)
Abstract
Background and Aim: A well-designed desk and chair, in addition to proper learning, can prevent changes in the user's physical form. Therefore, this study aimed to determine the anthropometric characteristics of students in the College of Agriculture and Natural Resources located at the University of Tehran to design an ergonomic table and chair.
Methods: In this research, 18 anthropometric characteristics including the popliteal height, knee height, shoulder height, eye height, sitting height, elbow support height, elbow height, knotted elbow length, hip-popliteal length, hip-knee length, thigh thickness, abdominal depth, chest depth, hip width, shoulder width, the transverse width of the elbows, height, and as well as weight for 260 students (130 girls and 130 boys) aged 18 to 35 years were investigated. To collect data, an anthropometric chamber and chair were used. Finally, according to the measured physical dimensions of the students, the Dimensions of ergonomic table and chair were calculated and designed according to the INSO 9697-1 standard.
Results: Anthropometric dimensions of students were obtained through mean, minimum, maximum, standard deviation, mean, and the percentile value of 2.5 to 97.5 using SPSS version 20 software. The results showed that the age of the user does not have a significant effect on the size of the table and the chair. Also, the results showed that there was a significant difference in popliteal height between girls and boys.
Conclusions: Considering the difference in dimensions between female and male students, it was found that the popliteal height in the percentile of 5 for boys is 4 cm more than girls. Therefore, using measured anthropometric characteristics, the dimensions of the chair and table ergonomics were designed in two sizes.
Jafar Akbari, Mahmood Abolghasemian, Amir Ghaffari, Fereydun Moghaddas, Mohammad Amin Mououdi, Shaghayegh Rahimi Kamal, Asoumeh Jozkanani,
Volume 9, Issue 1 (Iranian Journal of Ergonomics 2021)
Abstract
Background and Objectives: Presenteeism is introduced as a phenomenon according to which employees are physically present in the workplace but are functionally absent. This study aimed to investigate presenteeism and productivity loss associated with health problems among employees of the Iranian Gas Transmission Company (IGTC).
Methods: The participants were 2298 employees. Data collection instruments included the Stanford Presenteeism Scale (SPS-6) and the Health and Work Questionnaire (HWQ). Data analysis was performed using the multivariate logistic regression in SPSS software version 26.
Results: More than 52% of the participants (1189 people) had experienced presenteeism at least once a year, while a total of 1073 people (47%) were non-presenteists. The results showed that the HWQ subsets including productivity (P = 0.001), focus (P = 0.023), relationships with the manager or boss (P = 0.007), impatience and irritability (P = 0.026), workplace satisfaction (P = 0.038) and finally the total HWQ score (P = 0.011) had a statistically significant relationship with presenteeism.
Conclusion: Presenteeism reduces the productivity of the workforce by reducing individual productivity, reducing people's ability to concentrate, the inappropriate perception of the relationship with the manager/ boss, increasing their impatience, irritability and level of work-related stress and eventually reducing the level of people's satisfaction with the work environment. This imposes a lot of costs on the organization.
Arezoo Sammak Amani, Mohammad Amin Mououdi, Morteza Mahdavi, Fariba Ghaempanah,
Volume 9, Issue 3 (Iranian Journal of Ergonomics 2021)
Abstract
Background and Objectives: For many employees, students and “Behind the desk jobs”, most of the daily work is done while sitting on a chair and behind a desk. This happens while many studies are associating long-term sedentary posture with musculoskeletal and cardiovascular diseases, etc. The aim of the present research is to design a tool that helps to change the working posture of people who work at sedentary workstations from sitting to stand-sit posture.
Methods: The measurements needed to design a desk converter were extracted from the existing anthropometric data of the Iranian community between the ages of 6-19 and 20-60 for both sexes, using 4 anthropometric parameters of elbow (to floor) height sitting, eye height sitting, elbow height standing and eye height standing. These values were used to obtain the difference between the required work surface of the hand while sitting and standing (keyboard position) and the difference of the required work surface of the eye while sitting and standing (display position). Due to the adjustability of this tool, 5th percentile of women and 95th percentile of men were used to achieve the required range of changes.
Results: The desk converter constitutes two parts, 1. Top surface (meant for monitor) and 2. the keyboard tray. The difference in the height of these two surfaces was calculated 12cm. The maximum height of the desk converter (adjustable range) for both age groups was 68 cm due to changes in sitting and standing elbow height. The width and depth of the desk are set at 90 by 50 cm, and the keyboard and mouse surface, with a width equal to the desk’s and a depth of 20 cm, creates sufficient and comfortable space for users.
Conclusion: It is envisioned that by using this tool and changing the posture of individuals from an entirely sitting posture to standing and sitting alternation, a contribution to the reduction of musculoskeletal, cardiovascular, diabetes and cancer problems can be made.
Morteza Mahdavi, Arezo Sammak Amani, Mohammad Amin Mououdi, Hadi Asghari,
Volume 10, Issue 2 (Iranian Journal of Ergonomics 2022)
Abstract
Objectives: Providing safety for human resources in the industry is very important. Safety shoes are one of the most common PPEs that protect the foot against potential hazards. This study aimed to evaluate the discomfort and usability of safety shoes in different industries of Mazandaran province to find gaps in the quality of design and improve the design of safety shoes.
Methods: This was a cross-sectional study and was conducted in 2021.This study included employees of 11 different industrial companies that used seven safety shoe brands. They answered two researcher-made questionnaires, LPD (discomfort and general satisfaction) and SFUQ (usability). Data analysis was performed with Spearman rank correlation coefficient while Pearson correlation coefficient, and ANOVA test were also performed.
Results: In total, 226 men with a mean age of 36.33 ± 7.4 years were included in this study. The participants reported the lowest usability for the brand G (3.3 and 3.99), and the least discomfort and the most usability index with the brand A (1.2 and 5.35). Overall, the highest satisfaction was reported for brand A and the lowest satisfaction to brand G.
Conclusion: The findings of this study showed that the main problem in comfort and usability is probably related to shoe molds because the manufacturers of safety shoes import molds from abroad that do not fit the anthropometric characteristics of Iranian users’ feet.
Mohammad Amin Mououdi, Arezoo Sammak Amani, Mohammad Taghipour,
Volume 11, Issue 2 (Iranian Journal of Ergonomics 2023)
Abstract
Objectives: Nowadays, workers are less mobile and more sedentary due to the use of modern technologies in the workplace, and the complications resulting from static work and fixed posture have caused numerous disorders, including musculoskeletal disorders. This study was conducted to evaluate the comfort and usability of the ergonomic sit-stand desk converter with the aim of preventing disorders caused by constant sitting in workers.
Methods: 30 employees and faculty members of a university voluntarily participated in this study and provided informed consent. After the necessary explanations, subjects were provided with two researcher-created questionnaires ( Local Perceived Discomfort (LPD) and Sit-Stand Desk Converter Usability Questionnaire (SSDCUQ)), two methods of posture analysis, two methods of Workstation evaluation and general satisfaction along with 20-8-2 software and an ergonomic desk converter. After the test period, the data was analyzed using SPSS version 22 software and statistical tests such as mean, standard deviation, Spearman's rank correlation coefficient and Pearson correlation coefficient.
Results: The overall mean LPD in the different body parts was 0.48 ± 0.87, indicating that the converter functions in the range of no problem to very little discomfort. The average overall satisfaction with the function of the converter was 3.18 ± 1.08 ,which is in the medium to good range. When analysing the different sitting and standing postures, a significant correlation was also found between the different situations of using the converter (P<0.0005), which indicates an improvement in sitting and standing posture while using the converter.
Conclusion: Height-adjustable workstations are a good choice to reduce sitting time and improve posture. Despite the improvement in sitting and standing posture when using the converter, there are limitations, such as ignoring the software warnings for sitting and standing in the mechanical converter studied.
Mousa Nazari, Arezoo Sammak Amani, Mohammad Amin Mououdi, Mohammad Mahdi Alyan Nezhadi,
Volume 11, Issue 4 (Iranian Journal of Ergonomics 2024)
Abstract
Objectives: Work-related musculoskeletal Disorders (WMSDs) are the most significant challenges in both developing and developed countries, affecting the majority of individuals throughout their lives. Considering the detrimental effects of musculoskeletal disorders on the productivity and general health of employees, this research utilizes the Cornell Musculoskeletal Disorder Questionnaire (CMDQ) to develop an intelligent model for assessing and predicting the levels of musculoskeletal disorders.
Methods: In this descriptive-analytical study, 810 employees from five organizations (in four occupational categories, including administrative, technical, production, and services) completed the CMDQ voluntarily. After collecting the questionnaire and performing relevant statistical analyses, data normalization and clustering based on the K-Means method were used to determine levels of musculoskeletal disorders. Finally, the multilayer perceptron artificial neural network was trained to predict the levels of musculoskeletal disorders; moreover, the criteria of precision, accuracy, recall, and F1-score were used to evaluate the proposed model.
Results: The performance of the proposed model in predicting the levels of musculoskeletal disorders is presented in two scenarios (use and non-use of the Synthetic Minority Oversampling Technique (SMOTE) method) based on the evaluation criteria provided. The accuracy, precision, recall, and F1-score values were 0.724, 0.709, 0.756, and 0.720, respectively. The appropriate accuracy and precision in the proposed model indicate its capability to identify the levels of musculoskeletal disorders in individuals and help healthcare professionals take necessary measures to prevent and predict them.
Conclusion: This study employs the CMDQ questionnaire and artificial intelligence to analyze musculoskeletal disorders in the workplace. The proposed model demonstrates significant accuracy and precision compared to similar studies. The results indicate that this model can be utilized to identify and predict musculoskeletal disorders in organizational employees, offering the potential to expedite the identification process and reduce costs.
