Journal of Health and Safety at Work

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Introduction: Work-related musculoskeleta ldisorders (WMSDs) of upperlimbs (UL)in the last 35 years have become extremely widespread, reaching epidemiclevels, inalladv ancedindustrializedcountries. They are considered the main cause of disability, time off work, and requests for healthcare

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Method and Materials: For detailed risk assessment, ISO -11228-3 is the preferred method. It is recommended for the specific purposes of ISO -11228-3(2007) because, given the knowledge at the time of publication, it considers all the relevant risk factors, is also applicable to “multitask jobs”, and provides criteria - based on extensive epidemiological data - for forecasting the occurrence of UL-WMSD (upper limb work-related musculoskeletal disorders) in exposed working populations. In this method is the ratio between the number of actual technical actions, ATA, carried out during a work shift and the number of reference technical actions, RTA, for each upper limb, specifically determined in the scenario under examination.

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Results: Results shown in 4 workstations include 35 task in an automotive industry. One of them is red and another’s are green.

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Conclusion: This method is suitable, quickly and very easy to use for assessment of ergonomics situation in work.

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Introduction: Low back pain (LBP) is a common and costly health problem. It has high prevalence in nursing job and caused shortage of nursing staff. This study was conducted to determine the prevalence of LBP, knowledge level of LBP risk factors and assess relationship between LBP prevalence and nurses’ knowledge level of LBP risk factors among nurses of Shiraz University of Medical Sciences (SUMS).

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Material and Method: In this cross-sectional study, 118 randomly selected registered nurses participated from SUMS hospitals with at least one year of job tenure. In order to assess nurses’ knowledge of LBP risk factors, a self-administered survey questionnaire consisted of four parts was used as data collecting tool. Statistical analyses were performed using SPSS (version 11.5). Duncan, T-test and ANOVA tests were used for data analysis.

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Result: LBP prevalence rate was found to be 79.7% (94 nurses) during the previous year from which 12 nurses were male (63.2%) and 82 nurses were female (82.8%). Nurses’ knowledge level of LBP risk factors in different hospitals was not significantly different. The Results showed that nearly half of the nurses had poor knowledge about LBP risk factors and the remaining had good knowledge level. The main source of information about LBP risk factors among nurses were related to their university education.

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Conclusion: A high prevalence of the LBP was found among nurses working at SUMS hospital. Knowledge level of nurses about LBP risk factors needs improvement. In addition to university education, which is the main source of information of nurses about LBP risk factors, on-the-job training seems essential in this field.

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Introduction: work related musculoskeletal disorders are the most wide spread type of occupational diseases among workers. Awkward body postures during work and manual material handling are among the most important risk factors of musculoskeletal disorders in different jobs. Due to importance of recognizing these factors prevalence and risk factor of work related musculoskeletal disorders, this research was aimed to study the among employees of Kashan City’s Saipa automobile industry in 2011.

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Material and Method: This study is a descriptive-cross sectional study conducted among workers with manual material handling 37 activities and 84 work duties. To recognize musculoskeletal disorders, body map questionnaire was applied and occupational risk factors were evaluated using Key Index Method (KIM). Data was analyzed using SPSS and Excel software.

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Result: Highest prevalence of musculoskeletal disorders was in low and upper back region (%92). Based on the results from KIM, workers in the installing the tire, shuttle-aided fitting of seat, and engine work station had higher risk level with the scores of 66, 52 and 52, respectively. Risk level among three individuals (%3.6) was at 1, 40 (%47.6) at 2, 38 (%45.2) risk level 3, and 3 (%3.6) at 4.

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Conclusion: Awkward body posture, improper twisting and flexion of low back were major risk factor among worker doing manual material handling tasks. Regarding the high prevalence of musculoskeletal disorders, appropriate ergonomic interventions such as engineering and organization interactions can reduce this risk factors (posture, heavy load, duration, workplace conditions) as much as the risk level reach to an acceptable level.

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Introduction: The bank employees usually require the use of computers for long duration in a static position to get the work done. The present study aimed to evaluate the risk factors for musculoskeletal disorder using the ROSA method among the employees of Sepah Bank. An ergonomic intervention was also performed in order to improve the working conditions.

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Material and Methods: This interventional descriptive-analytical study was carried out among 165 office employees of central building of Sepah Bank. Using random sampling, the subjects were initially divided into two groups of case and control. Before and after the intervention, ROSA method and Nordic questionnaire was respectively used to evaluate the risk factors that cause musculoskeletal disorders and the prevalence of musculoskeletal disorders. The data were collected two weeks prior the interventions and 9 months after the interventions. SPSS software version 16 was utilized for data analysis and the effectiveness of intervention was determined.

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Results: Before the intervention, the mean ROSA scores of all groups' workstations were above 5 with high risk. The results obtained 9 months after the interventions manifested a statistically significant decrease (P<0.001) in the ROSA mean scores and its components in the groups who received the interventions. 9 months after the intervention, the prevalence of musculoskeletal disorders among the subjects who had received intervention showed a significant reduction, as well (0.001> p).

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Conclusion: Using the ROSA technique was seemed to be beneficialto assess the ergonomic risk factors of office works, and the deficiencies in the workstation can be identified through this method. Moreover,by design and implementation of an educational intervention program along with engineering interventions which comply with the elements of this technique, the defects can be eliminated.

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Introduction: In Laboratory accusations a wide range of hand-held tools are used due to nature of their work. Long-term and repeated use of these tools has led the laboratory workers to suffer from upper limb disorders. The present study was designed and implemented with the aim of investigating the usability of different models of pipettes used in the laboratories of the Tehran University of Medical Sciences, employing subjective assessment methods for selecting the best pipette models.

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Material and Method: This cross-sectional and analytical-descriptive study was performed among 35 laboratories employees of Tehran University of Medical Sciences. First, four models of the widely used pipettes were selected and their usability-related characteristics were investigated by a visual analog scale (VAS). Judgments concerned the usability of the pipettes done based on the criteria provided by the International Organization for Standardization 9241-11(1998) and 20282-2(2006). Data analysis was performed, using SPSS software version 22.

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Result: The overall evaluation of the users in relation to the characteristics of the pipettes indicated that the highest VAS score was belonged to pipette A, C, and D, respectively. Furthermore, pipette B was selected as the most undesirable one by users. Results related to the usability criteria of pipette showed that of the four models of study pipettes, pipette A has been ranked first in two criteria (satisfaction and effectiveness). Regarding the efficiency, the first rank was for C pipette and the second rank was for pipette A. Pipette B obtained the lowest scores for all given criteria.

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Conclusion: Shorter and lighter pipettes, which were designed according to ergonomic principles, had greater usability from the perspective of users and it could cause a better subjective assessment comparing to the other models.

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Background: High prevalence of musculoskeletal disorders have been reported by office workers due to the nature of their work. This study aimed to evaluate the prevalence of musculoskeletal disorders in a group of office workers and also to determine the ergonomics risk factors affecting these disorders.
 

Methods: This is a cross-sectional study, performed among 174 office workers in Kerman city, Iran. Data collection tools included demographic and organization information form, the Nordic Musculoskeletal Questinnaire (NMQ), and the Rapid Office Strain Assessment (ROSA) method. The gathered data were analyzed by SPSS software version 16 using descriptive statistics, chi-square test, and logistic regression.
 

Findings: The prevalence of symptoms of musculoskeletal disorders (MSDs) in the past 12 months was reported 60.4 percent. What is more, significant associations were observed between job tenure and hours a day using computer with MSDs (P-value<0.05). In this sense, with  one unit increase in job tenure (years) and duration of computer use (hours per day), the probability of incidence of MSDs gone up 17.2 percent and 15.8 percent, respectively. Based on the statistical chi-square test, a significant relationship was reported between the incidence of MSDs and Rapid Office Strain Assessment method (P-value<0.05).
 

Conclution: According to results, ROSA assessment method is an efficient tool in the classification and identification of factors affecting the incidence of MSDs among office workers. Performing corrective measures in the dangerous work stations (the second level identified by ROSA technique), reducing the duration of computer use per day, and doing regular sport activities can be noted in order to decrease the prevalence of MSDs in the study group (office workers).

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Introduction: Physical workload is one of the main risk factors in developing of musculoskeletal disorders in construction workers. The current study was carried out to determine the prevalence of musculoskeletal disorders and its relationship with demographic characteristics and physical work load index (PWLI)in construction workers.  
Material and Methods: This investigation was a descriptive and cross-sectional study in which 162 subjects including 75 rebar and 87 bricklayer workers were participated. Nordic musculoskeletal and physical workload questionnaires were employed as the tools of this study. Chi-squared and logistic regression tests were used for statistical analysis in SPSS 21 software.
Results: The mean of age and working experience of construction workers were 34.6±8.6 and 11.2±6.8 years, respectively. The most prevalent symptoms were in the body regions of upper back (57.4%), lower back (35.8%), and neck (30.2%). In the univariate analysis, the musculoskeletal symptoms of shoulders, low back, feet, knees, and thighs with PWLI and the upper back pain with age, working experience, and working hours had significant relationships (P<0.05). According to logistic regression analysis, with the increase of the value of PWLI to more than 90 percentile, the chance of having symptoms of musculoskeletal disorders in low back, knees, and feet and also with the increase of working hour to more than 8 hours, the chance of having symptoms in low back and feet increased significantly.
Conclusion: The prevalence of musculoskeletal disorders was high in the studied construction workers. Most of the musculoskeletal symptoms were correlated with PWLI. Therefore, PWLI could be used to determine the construction jobs with the high risk of musculoskeletal disorders. To reduce the symptoms of musculoskeletal disorders in construction workers, the reduction of sources of physical workloads such as heavy material handling and awkward postures are proposed. It is also recommended that the working hours be limited to less than 8 hours.

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Introduction: Work-related musculoskeletal disorders (WMSDs) are one of the most important causes of absenteeism, increased costs and human injuries, which are very common in computer users. The purpose of this study was to investigate the effect of 8 weeks of corrective exercise on reducing the prevalence of musculoskeletal disorders (MSDs) in computer users working in a gas company.
Material and Methods: This cross-analytical study was conducted on 101 computer users working in a Gas Company in Qazvin city in 2019. Fourteen people participated in 8 weeks correction training intervention program (16 sessions in 1 hour and 2 times a week). Nordic questionnaire and body map were used in order to investigate the prevalence and severity of MSDs. The data were analyzed using Kolmogorov-Smirnov, Cramer V, McNamar, Paired sample t-test and Wilcoxon tests in SPSS version 23 software.
Results: The most common disorders were shoulder (64.3%), waist (42.9%) and neck (35.7%) regions among computer users during the last week before intervention. The prevalence of MSDsby strength and flexion exercises in neck and shoulder regions with 95% and 99% confidence showed a significant decrease before and after intervention. The incidence of discomfort in the waist region decreased by 35.8% after intervention and in other regions decreased by at least 7.1%.
Conclusion: The results of this study showed that implementation of corrective training intervention program by exercise specialists can increase muscle stretch and consequently decrease the prevalence of MSDs7.1%- 64.3%.

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Introduction: Musculoskeletal disorders (MSDs) are prevalent in work settings and are associated with high rate of prevalence and costs. Musculoskeletal conditions have multifaceted nature, and occupational factors play an important role in their development. The aim of this study was to identify the risk factors of work-related musculoskeletal disorders in the working population in Iran during 2000 to 2015.
Material and Methods: Using the appropriate search terms, articles published in the journals, student thesis, and those presented at the conferences were searched through authentic English databases (Google Scholar, Scopus, PubMed) and Farsi ones (Magiran, SID, IranMedex, Irandoc). Following removal of duplicate citations and irrelevant studies, the full texts of the remaining publications were prepared and assessed for more detail.
Results: Perceived discomfort in low back region obtained the highest score in workers of industrial, administrative, service, and agricultural settings. However, in the handicraft and educational groups, the highest percentage of discomfort was belonged to neck (66.7%). Findings showed that the most commonly used techniques for evaluation of musculoskeletal disorders and risk factors were, respectively, Nordic questionnaire (NMQ) (76%) and REBA (13.9%). Moreover, all identified risk factors were classified into eleven groups including: biomechanical, work environment design, tools, equipment, temporal aspects of job design, job content, organizational aspects, economic and financial issues, social aspects, individual characteristics, and training.
Conclusion: Overall, a wide range of risk factors reported in the previous studies were categorized in the present review. The results are suggested to be considered by managers and decision makers as a framework to take measures for controlling musculoskeletal disorders to accomplish the goal of ergonomics, which is productivity and well-being.

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Introduction: Long-term exposure to hand-arm vibration causes musculoskeletal disorders mainly in hand and shoulder. The purpose of this study was to determine the effect of sport and using anti-vibration gloves on the grip strength of workers exposed to the hand-arm vibration.
Material and Methods: In this descriptive-interventionist study, 41workers working in one of the Isfahan metal industries were studied. Data were collected by the demographic questionnaire, hand-arm vibration acceleration measurement was performed based on the ISO 5349 standard and grip strength was measured using the dynamometer device model Jamar. The investigations were performed on 3 groups including sporting moves, using of anti-vibration gloves and combination of sporting move and using of gloves. Twenty workers were selected as control group without exposure to any hand-arm vibration. Data were analyzed by the SPSS-21 software.
Results: Workers’ grip strength difference was significant before and after vibration (PValue<0.001) and grip strength had significant and inverse relation with vibration (PValue<0.001, R= -0.411). Grip strength was higher in the group that used anti-vibration gloves accompanied with the sporting moves compared to before the intervention and significant relation was observed (PValue<0.001).
Conclusion: Vibration affects decreasing in grip strength and grip strength itself can be used as a screening measure for those workers exposed to the risk and diseases related to the vibration. Regular sporting moves and using anti-vibration gloves are effective on improvement of workers’ grip strength and preventing vibration-induced complications.

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Introduction: Working with a computer and workplace conditions expose people to risk factors of musculoskeletal disorders (MSDs). This study aimed to assess posture, examine MSDs, and determine, weigh and prioritize the risk factors among computer users by a neural network algorithm. 
Material and Methods: This descriptive-analytical cross-sectional study was conducted in six phases on computer users in 2019. The status of MSDs was determined via Nordic musculoskeletal questionnaire (NMQ). The factors affecting these disorders were determined by the ROSA method, and then these factors were weighed by the neural network algorithm. The data were analyzed in IBM SPSS Modeler.
Results: The mean age and work experience of the users were 34 ± 6.9 and 1.5 ± 0.7 years, respectively. Most of years were observed at the lower back, neck, and upper back, respectively. The final mean scores of the chair, telephone-monitor, and mouse-keyboard were 3.7 ± 1, 3.6 ± 1.1, and 3.65 ± 1.2, respectively and the final mean score of ROSA was 4.4 ± 0.9. The greatest correlation with the ROSA score was observed in chair (R2 = 0.46), followed by telephone-monitor (R2 = 0.43), and mouse-keyboard (R2 = 0.42). The highest predictor importance of the effective factors based on the neural network algorithm prioritization belonged to the chair (48%), followed by telephone-monitor (28%) and mouse-keyboard (24%). The accuracy of the neural network algorithm in examining the effect of factors on musculoskeletal disorders was 98% based on the ROSA score.
Conclusion: Factors affecting years due to working with computers are the chair, telephone-monitor, and mouse-keyboard, respectively, as prioritized by the neural network algorithm. These disorders can be prevented by ergonomic modification of users’ chairs and correct placement of the monitor and telephone.

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Introduction: Musculoskeletal disorders (MSDs) have a multifactorial nature. Biomechanical factors are one of the most important factors. Consequently, the precise identification of effective factors plays a significant role in controlling and preventing these disorders. Therefore, the current study aimed to identify the awkward upper body postures and their effect on the prevalence of MSDs in office workers in both women and men groups by objective methods.
Material and Methods: In this cross-sectional study, the participants were 36 office workers (18 women and 18 men). The prevalence of musculoskeletal discomfort was evaluated using the Nordic questionnaire. The upper limbs posture, including the back, neck, and wrists, was evaluated continuously with an electronic inclinometer and an electrogoniometer for 30 min, followed by analyzing the collected data.
Results: The results revealed that the highest prevalence of musculoskeletal symptoms in both gender groups was in the neck (58.33%), trunk (52.77%), and wrist (47.22%), respectively. The results disclosed that the median trunk and neck flexion in both groups is over 20° and the posture angle in women is higher than that of men (P<0.05). The results showed that pain and discomfort in the trunk and neck in both gender groups have a significant relationship with the median posture angle (P<0.05). Also, the wrist posture in both gender groups during work was in extension and static condition.
Conclusion: Based on the results of this study, the prevalence of disorders in women was higher than in men. Although the tasks performed in both groups were similar, the assessment of postures disclosed that women office workers had more awkward postures in the trunk and neck than men. In both groups, the prevalence of musculoskeletal discomfort had a significant relationship with awkward postures in the trunk and neck. According to the results of the current study, ergonomic interventions are recommended to reduce awkward postures and to prevent MSDs, particularly among women office workers.

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Introduction: Work-related musculoskeletal disorders (WMSDs) are a prevalent occupational health concern, influenced by both physical and psychosocial factors. Valid questionnaires offer a cost-effective and efficient means of evaluating WMSDs. This study aimed to validate the Persian version of the MDRF questionnaire, assess its applicability in Iran, and investigate the prevalence of WMSDs among employees in an automotive industry.
Material and Methods: This descriptive cross-sectional study was conducted among 100 employees (50 production line workers and 50 office workers) in Kerman province. The linguistic validity of the questionnaire and its translation were ensured using the Backward-Forward method. Content validity was assessed through CVI and CVR indexes. To evaluate the questionnaire’s reliability and agreement, Cronbach’s alpha and ICC were employed. User responses from the first and second series of the questionnaires were validated using Kappa and Spearman’s tests.
Results: Results indicated high reliability which was achieved by Cronbach’s alpha and ICC values of 0.960 and 0.925, respectively. The questionnaire’s validity was acceptable based on CVR and CVI tests. The prevalence of WMSDs was the highest in the lower back for both production line and office workers over the past year. The job satisfaction factor exhibited the highest risk level among the questionnaire’s four subgroups. Approximately 85% of participants were classified as having a high or very high-risk level, reflecting concerning conditions among the employees. The prevalence of WMSDs in different body parts significantly correlated with all physical and psychosocial stress factors.
Conclusion: This research highlights the influence of diverse physical and psychosocial risk factors on the occurrence of WMSDs among both occupational workers and office employees. Also, the MDRF questionnaire, whose high applicability in assessing the WMSDs risk factors was proven in this study, is an effective tool for prioritizing, planning, and executing educational and preventive measures within the workforce community to mitigate and prevent WMSDs. 

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Introduction: Lifting loads in awkward postures is a main cause of low back musculoskeletal disorders. In this context, researchers have used various indicators to determine the relationship between biomechanical variables and the risk of these disorders. This study aimed to investigate the correlation between plantar pressure distribution and the values of UTAH back-compressive forces (BCF) and lifting index (LI) during symmetrical load-lifting tasks.
Material and Methods: Thirteen healthy men, aged 25 to 35, took part in this study. The participants were instructed to symmetrically lift loads weighing 7.5 kg and 15 kg in 15 different postures, considering three horizontal distances (A, B, C) and five different heights (1-5). Pressure on the foot soles was recorded using 16 force-sensitive resistors (FSR) corresponding to eight anatomical areas on each foot. The BCF and LI were also calculated using the UTAH method and the NIOSH equation, respectively. Statistical analysis was performed using SPSS (version 21) software.
Results: Based on the results, when the load was closest to the body (A1-A5), the highest pressure was recorded in the heel and the 4th and 5th metatarsal of both feet. In lifting a load of 15 kg in the A2, B1, B2, C1, C2 postures and lifting a load of 7.5 kg in the C2 posture, the average BCF exceeded 700 pounds. The LI was greater than 1 for specific postures (B1, B2, B4, B5, C1-C5) at 15 kg and (C1, C2, C4, C5) at 7.5 kg load-lifting. During the 7.5 kg and 15 kg load-lifting, there was a significant correlation between the plantar pressure and the values of LI and UTAH (p-values < 0.05) in most postures.
Conclusion: The results showed a significant correlation between plantar pressure distribution and load-lifting postures. The study findings, which identify risk levels associated with lifting postures, lay the groundwork for future research aimed at categorizing safe and unsafe plantar pressure patterns.