Lean Production and Its Impact on Worker Health

Lean is currently applied successfully in many industrial sectors. However, its value and impact on human health is not fully understood. To gain a better understanding, this chapter explores how ergonomics force and fatigue evaluation methods can be applied in a manner to enhance lean initiatives. These methods incorporate ergonomic-related variables of force type, force duration, force frequency, and degree of awkward posture, and incorporate the recommended cumulative rest allowance (RCRA) model as a practical fatigue-based metric. These methods and their application are discussed.

A Comparison of Multiple Machine Learning Algorithms to Predict Whole-Body Vibration Exposure of Dumper Operators in Iron Ore Mines in India

Background: This study deals with some factors that influence the exposure of whole-body vibration (WBV) of dumper operators in surface mines. The study also highlights the approach to improve the multivariate linear analysis outcomes when collinearity exists between certain factor pairs. Material and Methods: A total number of 130 vibration readings was taken from two adjacent surface iron ore mines. The frequency-weighted RMS acceleration was used for the WBV exposure assessment of the dumper operators. The factors considered in this study are age, weight, seat backrest height, awkward posture, the machine age, load tonnage, dumper speed and haul road condition. Four machine learning models were explored through the empirical training-testing approach. Results: The bootstrap linear regression model was found to be the best model based on performance and predictability when compared to multiple linear regression, LASSO regression, and decision tree. Results revealed that multiple factors influence WBV exposure. The significant factors are: weight of operators (regression coefficient β=-0.005, p<0.001), awkward posture (β=0.033, p<0.001), load tonnage (β=-0.026, p<0.05), dumper speed (β=0.008, p<0.001) and poor haul road condition (β=0.015, p<0.001). Conclusion: The bootstrap linear regression model produced efficient results for the dataset which was characterized by collinearity. WBV exposure is multifactorial. Regular monitoring of WBV exposure and corrective actions through appropriate prevention programs including the ergonomic design of the seat would increase the health and safety of operators.

Perbaikan Sistem Kerja Proses Pemasangan Ban Truk dengan Perancangan Peralatan Pendukung Menggunakan QFD dan REBA

PT.X as one of the heavy equipment manufacturing company are producing mining and non-mining transportation product (e.g. Semi Side Tipper (SST) & Dolly). In producing those kinds of products that mostly using tires, there is a process area to do mounting truck tire. Based on interviews and direct observation results, there is a symptom of Cumulative Trauma Disorders (CTD), especially in the low back area. The low back pain experienced by the operators is caused by an awkward posture that resulted from Manual Material Handling (MMH) in this process. Lifting and holding the tire that is located on the floor with diameter 1.2m, height 0.3m, and weight 90 Kg also the reasons why the awkward posture appears during the mounting truck tire process. Using Rapid Entire Body Assessment (REBA), Nordic Questionnaire, and followed by the Quality Function Deployment (QFD) approach for product design are used to do the improvement for the process. In the end, these ergonomics issues are solved by developing material handling tools that can minimize the risk and symptoms of CTDs. It can be shown by initially REBA score is on level 11 (Very High Risk) to level 7 (Medium Risk) and for the Nordic result from 7 body parts that feel discomfort, now it just becomes 1 body parts feel discomfort.

Association of lumbar spine mobility and hamstring tightness in dental practitioners

Introduction and Aim: The decrease in lumbar spine mobility and hamstring tightness can be caused due to the lack of regular exercise and awkward postures exposed at the workplace due to an individual's occupation. It can be expressed due to the awkward posture during dental practice as well and this can be controlled by doing regular exercises.The aim of the present study is to analyze the association of lumbar spine mobility and hamstring tightness in dental practitioners. Materials and Methods: The study is conducted in a Private dental college and hospital for the dental practitioners who work for more than 4 hours in a day. The hamstring tightness is measured using the goniometer and lumbar spine flexibility is measured using an inch tape. The measurements are tabulated and analyzed statistically for the correlation of lumbar spine flexibility with hamstring tightness using the SPSS tool. Results: The collected data are analyzed statistically using correlation coefficient and the findings concluded that they have a low positive correlation. The mean value of lumbar flexion range is 19.37 cm and mean value of the hamstring tightness is 27.8°, the correlation coefficient r is 0.473. Majority of female participants have increased hamstring tightness with a maximum range of 30° and around 11% of male participants have a restriction range of 25°. Similarly, around 8% of female participants have a lumbar flexion range of around 21cm, However, there is no significant difference between the gender in both the variables with p value equals 0.35 and 0.53 (p > 0.05) respectively. Conclusion: From the obtained results it can be concluded that there is a low positive correlation between hamstring tightness and the lumbar flexion range. The findings suggest that the dental practitioners are prone to hamstring tightness which in turn can induce reduced lumbar spine mobility and impacts stress on the lumbar spine leading to low back pain.

PREVALENCE OF NECK PAIN AMONG TAILORS IN NORTH GUJARAT - A CROSS SECTIONAL STUDY

Background: - Neck pain is one of the common musculoskeletal problems faced by tailors due to constant work on the sewing machine with the awkward posture. Aim:-The aim of study is to nd out the prevalence of neck pain among Tailors. Objective:-To nd out the prevalence of neck pain among Tailors use of self questionnaire. Materials And Methodology:-Across sectional study was performed among 100 tailors working in North Gujarat to determine the prevalence of neck pain in them. Aself – questionnaire was used. Result: - 91% prevalence of neck pain was found among the tailors in North Gujarat. Also 67% tailors have activity limitation. Conclusion: -The prevalence of neck pain among Tailors in North Gujarat is found to be highest (91%). Neck pain is one of the common condition contributing to the increase in functional disability

Pattern of Household Activities and its Effects on Low Back Pain Among Bangladeshi Housewives

Background: Housework is traditionally an unpaid labour performed by women. It involves routine and compulsory household maintenance tasks can create musculoskeletal disorder like Law back pain (LBP). Objective: The main objective of the study was to identify the effects of household activities on LBP among Bangladeshi housewives. Methods: A descriptive cross-sectional study was carried out among 255 respondents. At the Musculoskeletal department of Centre for the Rehabilitation of the Paralysed (CRP), Savar, Dhaka. The questionnaire was designed according to Bangladesh perspectives regarding household activities that housewife do at home. Severity of pain was assessed using Visual Analogue Scale (VAS) and data ware collected using face to face interview. Results: Study found that household activities like cooking and chopping (p<.0001), washing dish and cloth (p<.0001), sweeping floor/cleaning toilet (p<.0001) were significantly associated with LBP. The results from regression analysis showed that having LBP compare with the time duration of cooking (OR=11.2; CI=2.62-47.73), chopping (OR=2.67; CI=1.44-4.93), washing dish (OR=3.33; CI=1.50-7.39), washing cloth (OR=5.71; CI=2.94-11.10), sweeping floor (OR=4.71; CI=2.33-9.53) was significantly higher among housewife than who don’t do this activity at home. Conclusion: This study revealed that all of married women had to do their household activities for a long period in awkward posture. Elderly housewives suffer more, as the duration of married life and duration of doing household activities are high among them. Among the activities coking, chopping, washing dish, washing cloth, lift heavy objects and sweeping the floor/cleaning toilet were done by maximum housewives. Bangladesh Med Res Counc Bull 2020; 46(3): 189-195

Analisis Tingkat Postur Kerja Dan Musculoskeletal Disorders pada Pekerja di Pabrik Roti Latansa Gontor

The La Tansa bakery industry is a formal industrial sector that makes bread, some process activities are still repeated manually. This condition will cause the prevalence of MSD complaints because the worker's body position is bent. The purpose of this study was to assess the level of risk of injury using the Quick Exposure Check (QEC) questionnaire and to assess complaints about the impact of this awkward posture using the Nordic Body Map (NBM) questionnaire. This type of research was descriptively carried out at the Latansa Bread Factory, Gontor Ponorogo in May 2020 with a total of 9 respondents. The research results will be analyzed using the Excel program. Based on the results of research on the distribution of questionnaires conducted by researchers and the workers themselves, it shows that the level of risk of injury to 7 out of 9 workers is at the level of 72.8% - 82.7%, which means that research and changes must be carried out as soon as possible. The results of MSD's complaint assessment among workers showed that all were categorized as having moderate complaints. The advice given to the Latansa Bread Factory is to design a chair and table for workers so as to minimize the risk of injury and create effective, safe, comfortable and efficient working condition.

Office Ergonomics Assessment dengan Menggunakan MIRTH Office

The computerized system is closely related to today’s office works. Computer works with high intensity of repetition and awkward posture can cause harm or risk. This can cause discomfort in several areas of the body. Therefore, an office ergonomics assessment that focuses on humans as the most important component is needed to determine the impact and causes of the discomfort problem. In this study, MIRTH Office is used as the assessment tools. The questionnaire consists of two parts, namely general information and conformity assessment. The data processing stage in this study consisted of problem identification and problem grouping. The results showed that most of the respondents experienced pain in the neck, shoulders, elbows, wrists and lower back. These results indicate the need of ergonomics intervention as early as possible to prevent the risk of musculoskeletal disorders.

ASSESSMENT OF WORK POSTURES ON NON-MECHANICAL RICE HARVESTING (CASE STUDIES IN BANTUL AND SLEMAN DISTRICTS, DIY PROVINCE)

Rice harvesting is a high ergonomic risk due to the working position, an awkward posture, and the repetition activity. Rice harvesting causes body pain in the part of low back, hand, and wrist. This study aims to (1) identify the characteristics of non-mechanical rice harvesting; (2) determine the working posture of rice harvesters using the Ovako Working Assessment System (OWAS) method, Quick Exposure Checklist (QEC), Rapid Entire Body Assessment (REBA), Postural Ergonomics Risk Assessment (PERA); and (3) determine the best method to assess harvesters work posture. An observation was conducted to nine of healthy workers in Bantul and Sleman districts, Daerah Istimewa Yogyakarta (DIY) province. The questionnaire was set to collect respondent demographics data. Data for harvester body posture (neck, trunk, leg, wrist, lifting load, shoulder) repetition, duration and force were collected by observation in the field. A sickle was used to cut rice straw, while a manual gepyok and mobile hand thresher was used to threshing rice panicles. Four methods were applied to assess the work posture, i.e., OWAS, QEC, REBA, PERA methods. Based on observation, five workstations were identified: (1) cutting rice straw, (2) transporting rice straw, (3) threshing of panicles, (4) sorting, and (5) packaging and transporting. REBA and PERA showed a similar trend of the ergonomic risk, high to low risk took place in workstation transporting rice straw, packaging and transporting, cutting, and threshing. The assessment of work posture that is most suitable for non-mechanical harvesting methods was the REBA method with an accuracy of 92.9%.

Prevalence of musculoskeletal disorders and its related factors in office workers of Minab Health centers by ROSA Technique

Introduction: Prevalence of musculoskeletal disorders (MSDs) is high among office workers. One of the most important risk factors of these disorders is awkward posture and inappropriate environmental conditions. So, this study was carried out to determine frequency of MSDS and its related risk factors among the office workers of Minab city healthcare centers in 2018. Materials and Methods: This cross-sectional study was conducted on 104 staff in Minab city health care centers. Nordic musculoskeletal disorders questionnaire was applied to determine the prevalence of MSDs and Rapid Office Strain Assessment (ROSA) method was used for posture analysis. The data were analyzed by SPSS version 21 using descriptive statistics and chi-square test. Excel software was used to plot the graph. Results: The highest prevalence rates of MSDs were reported in low back (63.5%), neck (51.9%) and upper back (50%). There was no significant difference between MSDs and age, sex and BMI (P˃0.05) but there was a significant relationship with work experience (P˂0.05). Totally, 36.6% of employees were placed in the first priority of corrective actions (i.e. the need for ergonomic interventions as soon as possible). There was a significant correlation between awkward posture and neck pain (P <0.05). Conclusion: The frequency of MSDS in health center office workers was high and neck pain was related to awkward posture.