مجله ارگونومی
سال چهارم شماره 2 (تابستان 1395)

Sleep disorder is very common among employees and is considered as one of the crucial health problems. There are strong correlations between poor sleep and sickness absence. The present study concerns the relationship between sleep quality and sleepiness and sickness absence.
this cross-sectional study was conducted on 400 employees of a gas company. The study data were collected using the Pittsburg Sleep Quality Index (PSQI) and the Karolinska Sleepiness Scale (KSS). Mann-Whitney U test, and Spearman’s correlation coefficient were applied for data analysis.
While 43.2% of the participants enjoyed satisfactory sleep quality, 56.8% had unsatisfactory sleep quality. The mean (SD) of KSS for the sample was 5.65 (2.19). Statistical tests indicated a significant difference between sickness absence of the personnel groups with good and poor sleep quality (p=0.0001). Spearman correlation coefficient (ρ = 0.777) indicated a statistically significant correlation between sleepiness index and sickness absence (p=0.0001).
The results showed a strong positive correlation between sleep quality and sleepiness index of the personnel and sickness absence; i.e. along with decline in sleep quality and incline in sleepiness, the personnel’s sickness absence increases.

The importance of product design has been increased dramatically in recent years due to economic considerations as well as changes in user preferences, policy making and legal needs. In response to this, and as one of the most influential branches in the field of product design (in terms of the fit between product and user), ergonomics has also been developed proportionally. The aim of this study was to review the most important considerations and different traditional and new approaches in product design as well as challenges and limitations in this regard.
A review was made of the relevant electronic databases including Ergonomics Abstracts, PubMed/Medline, Web of Science, Science Direct, Scopus and Google Scholar using the following keywords: product, design, ergonomic, design procedures and design approach. The search was limited to full text articles in the English language published in peer reviewed journals between 1990 and 2015.
Comparison of the traditional and new approaches in product design indicates that the new approaches help designers to choose the best product model based various aspects and a more detailed interaction between the user and product. Ergonomic considerations in product design also include engineering and psychological aspects as well as taking into account abilities and limitations of both products and users to find a good fit between user and product.
The findings suggest that the traditional approaches in product design alone may not anymore guarantee the success of a product in the market, particularly in universal scale and for a wide range of users. In other words, consideration of various technical (in terms of user-product interaction) and legal (environment, sustainability, cost benefit, etc.) aspects in new ergonomic approaches may be taken into account to improve the quality and success of the products in the global market. Ergonomists may be encountered with some challenges to achieve this goal, but high quality ergonomic services can be considered as an effective solution in this regard.

Nominal noise reduction rate of the earmuff manufacturers can be different compared with the actual attenuation rate. The present study aimed to determine the actual noise reduction rate of current hearing protection devices using a microphone in real ear method.
In this study, five common ear muffs used in the Irans industries was investigated on 30 subjects under laboratory conditions. Noise reduction rates of ear muffs were measured based on the ISO 11904 standard, microphone in real ear method, using noise dosimeter (SVANTEK, model SV 102) equipped with a microphone SV 25 model which can install inside the ear. The ear muffs comfort was also assessed by the developed questionnaire.
The results showed that the real noise reduction rates of the ear muffs are between 49% to 86% nominal reduction rates. Moreover, the actual attenuations are much lower than the nominal reductions at low noise frequencies. The performances of ear muffs developed by Irainian and foreign manufacturers were not statisticaly different (pv> 0.05). Based on subjects comfort scores, comfort of ear muffs were within the acceptable range. The noise reduction rates of the different ear muffs of each model were not also statisticaly different (pv > 0.05).
Since the duration use of earmuff is important factor on the effective protection of hearing, irregular use of the ear muff can reduce real attenuation of the earmuff lower than the minimum rate acquired in this study. Proper training and adequate supervision on the proper use of the ear muff can affect earmuff fitting along with increasing of actual noise attenuation.

According to the effectiveness and low cost of prevention, ergonomic assessment methods as a means to predict the potential occurrence of injury are being used. The aim of present research was to assess validity and reliability of researcher/ made Ergonomic assessment test for freestyle wrestling skills.
in this research, According to the Jobs Ergonomic evaluation tests and wrestling pathology research, ergonomic evaluation test for wrestling skills (WSEAtest) was designed. Content and face validity were proved by using the opinions of Sports biomechanics and pathology experts, and physicians, physiotherapists, trainers and wrestlers of Freestyle national team. Also, Test was performed on three skills on two different days by 5 examiners using software kinovea 0.8.15 and Intra and inter-tester reliability, were calculated. After The Validation, WSEAtest was performed on movies of four selected skills of Iranian freestyle wrestlers in London 2012 Olympic games.
The injury exposure in various parts of body, traumatic factors related to the collisions and loads, and the athlete and environment conditions was consistent with wrestling Pathological Research and confirmed the validity of the test results.
WSEA test has good validity and reliability and trainers, specialists, and sports therapists can use this test to assess traumatic factors and identify priorities for training, corrective exercises in different wrestling levels, and the ages use.

In recent decades, owing to the advancement of technology, most jobs and occupations have been required using computers. Lack of information about ergonomics conditions has been resulted in various occupational injuries. Break time between hours work and doing some exercise help in reduction of musculoskeletal symptoms. The present study was an attempt to propound new ergo-feedback software and to assess its usability in office worker subjects.
In this study, 30 office workers were participated. In the first step, muscle-skeletal symptoms were checked by body map checklist. Then Borg score was completed by the participants after a work day. Then the software was run in their systems and they worked with it about two weeks. After two weeks the BORG scale was completed again and usability of software was evaluated by the SUS questionnaire. Data analysis was performed using descriptive statistics (mean and standard deviation) and Wilcoxon and chi-square tests. Statistical analysis was done by SPSS version 19.
Results showed that there was no significant difference between BORG scale pre-post intervention (P>0.05). The majority of the users satisfied the software and SUS score showed about 82.25 percent satisfaction among them.
According to this study, office workers were satisfied using this software and it can help in reducing musculoskeletal symptoms in prolonged time period.

Nursing in hospital because of the nature of the work, including jobs in which work-related musculoskeletal disorders are highly prevalent. MSDs cause of injury among nursing staff shows that the main cause of these injuries is the movement of patients. The aim of this study was to evaluate the risk of musculoskeletal disorders caused by movement of the patient's nursing staff of the hospital affiliated with the University of Medical Sciences Allah is done.
This cross-sectional study was conducted on 325 nurses from 30 wards of Baqiyatallah hospital during summer 2015. Data were collected using demographic and Body map Musculoskeletal Disorders Questionnaires and PTAI index checklist. Statistical analysis was performed using SPSS version 16.
Some form of musculoskeletal symptoms had been experienced during the last 12 months by78.3% of the nursing personnel. The results indicated that PTAI index score was significantly associated with musculoskeletal disorders occurrence(P According to the findings, PTAI is an appropriate tool for musculoskeletal disorders risk identification and assessment due to patient handling in nursing personnel

Job stress identified as imbalance between job needs with individual’s abilities & demands. Job stress has somatic, psychological and behavioral traumas. By this view, the main purpose of the present research is investigation of the effects of employee's job stress level on the emersion of organizational citizenship behavior in the among Mazandaran's SAMEN Finance & Credit Institute's subdivisions employees.
Material and In this correlation-descriptive study, 147 employees from SAMEN subdivisions of Mazandaran province were selected based on Census sampling method. Data were collected by using job stress and organizational citizenship behavior standard questionnaire. Data were analyzed by SPSS and LISREL software, and using descriptive statistics methods, Pearson correlation and SEM.
In the current study, there was a significant and inverse relationship between job stress and organizational citizenship behavior (R=-0.590, and P=0.001). The results of structural equation modeling and path analysis showed that the job stress and the most of its components were good predictors for organizational citizenship behavior.
Recent research has demonstrated that the job stress at work may increase performance employees-related problems. There is a relationship between job stress and organizational citizenship behavior, and the attention to the job stress level as a predictor of organizational citizenship behavior in employs is an essential issue.

Firefighting is one of the jobs that because of its job nature and high physical demands, required high physical and aerobic power. This study aimed at estimating the maximum work capacity of firefighters using the step test utilizing a height adjustable step.
Material and This cross-sectional descriptive study was conducted on 73 of firefighter. At first, demographic information was collected by questionnaire. Then a step with adjustable height was built and maximum aerobic capacities of participants were examined using Francis method. The results of the questionnaire and the step test were analyzed by SPSS 16 software.
the Pearson correlation coefficients of validity and reliability tests for the step used in the present study were obtained 0.979 and 0.983, respectively. Average maximum aerobic capacity of firefighters was calculated 3.65 (L.min-1) and 47.4 (ml.kg-1.min-1). Moreover, the results of statistical analysis revealed a significant relationship between body mass index and exercise and maximum aerobic capacity (p˂0.05). Also, there was not found any significant relationship among the maximum aerobic capacity, age, smoking and work-related fatigue (p>0.05).
The results of this study showed that Maximal oxygen uptake (vo2 max) and cardiopulmonary capacity of examined firefighters are greater than the minimum amount recommended by the international association of firefighters that can be due to the regular physical fitness programs conducted by the organization.