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Showing 8 results for Lak

S. A. R. Negahban, S. M. A. Mossavion, A. Ebrahimi Hariri, M. Mollakazemiha, M. Jalali,
Volume 3, Issue 2 (8-2013)
Abstract

Introduction: In Iran country, small enterprise with less than 10 workers comprise about %90 of all industries and 80% of working population. Noise, higher than the permissible level is among the hazardous agents, workers in these plants facing with. The aim of this study was to investigate the correlation between screening estimation and noise measurement in small plants.

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Material and Method: This cross-sectional study was conducted in 51 plants with less than 5 workers. Noise screening was done using screening from. Next, noise level was measured in all the plants by TES-1358 sound level meter and regular grid method. Data were analyzed using chi-square test and linear regression in SPSS version 16.

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Result: The mean (SD) scores of sound pressure level and screening form were 86.5 dBA (4.5) and 64.2 (9.4) in 51 understudy plants, respectively. According to the results of sound measurement, sound level in 34 plants (66.6%) exceeded the permissible level and in 17 plants (33.33%) was below the limit. The results of screening forms showed that 47 plants (92.16%) had permissible level of noise while noise in 4 (7.84%) was not in permissible level. Chi square test revealed no significant relationship between the results of the two methods, based on the permissible and impermissible limits (p-Value=0.288). Furthermore, according to the regression analysis, R2 was obtained 0.357.

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Conclusion: No correlation was shown between the results of the two methods used. Thus, it is recommended to change the parameters used in the noise screening form for small plants, with less than 5 workers.


R. Hajizadeh, M. H. Beheshti, I. Khodaparast, J. Malakouti, H. Rahimi,
Volume 3, Issue 4 (2-2014)
Abstract

Introduction: Heat stress in workplaces cause multiple problems such as thermal stresses, thermal discomfort and in more severe cases may lead to accidents and diseases related to excessive heat. The aim of this study was to evaluate heat stress adopting WBGT Index in some small enterprise in Qom city and also to examine the relationship between WBGT and physiological indices.

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Material and Method: This Cross-sectional study was conducted in 25 small workshops in Qom city including of 10 indoor and 15 outdoor workshops in August 2012. WBGT were measured according to the ISO7243 standard. The physiological responses including pulse rate, systolic and diastolic blood pressure were measured among 25 workers (one from each workshop).

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Result: The average WBGT index for indoor job were 27.55 Ċ among auto body repair, 27.45 Ċ in mechanics, 24.64 Ċ in painters, 26.73Ċ in welder and 25.89 Ċ in manufacturing doors and windows makers. For outdoor jobs as auto body repair, mechanics and painters it was 30.01 Ċ, and for welders and doors and windows makers 28.52 Ċ. Compared to the standard of ISO7243 WBGT all small workshops were higher than threshold limit. Auto body repair (30.22 Ċ) and painting (30.03 Ċ) workshops had highest WBGT. Average WBGT in auto body repair (as a job with most exposed to the open space and solar radiation) with welder and doors and windows, showed statistically significant differences T-test using WBGT with pulse rate, systolic and diastolic blood pressure did not have statistically significant (P>0.05). The findings indicated that workers are exposing to heat stress and doing more researches and representing preventive counter measures for the workers in this field are essential.

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Conclusion: Heat stress in almost all of the studied workplaces are higher than the recommended limits, and the outdoor workshops had the highest thermal stress, although heat stress did not show a significant correlation with the studied strains.


Mahdi Malakoutikhah, Ali Karimi, Mostafa Hosseini, Amir Rastgarkhaled,
Volume 7, Issue 1 (4-2017)
Abstract

Introduction: Work-Family Conflict can influence the physical and mental health of workers as a social parameter. The aim of this study is supposed to provide theoretical model of relationship between work-family conflict and occupational accidents, taking into account parameters such as job stress and general health of employees in a steel manufacturing industry.

Material and Method: Research population included workers of steel department of a steel manufacturing industry. This research was a cross-sectional study, and 270 individuals were selected in two groups, with an accident experience during lasts 5 years (case) and without (control). They responded to questionnaires including 4 parts, demographic, 18 questions of work-family conflict, 35 questions of job stress and, 28 questions of general health. Data were analyzed and introduced using AMOS software.

Result: Result showed that the model present an excellent goodness of fit and all of factors were significant between parameters (p<0.001). In addition, individual health and job stress with high coefficient could affect work-family conflict and work-family conflict was effective in the event of occupational accidents.

Conclusion: Reducing work-family conflict as a social parameter affecting stress can be effective in the reduction of occupational accidents. The organizational management system with optimization of this important factor can upgrade its level of occupational safety.


Asma Zare, Mahdi Malakouti Khah, Ehsan Garosi, Seifollah Gharib, Sayed Abolfazl Zakerian,
Volume 8, Issue 3 (9-2018)
Abstract

Introduction: Control room is one of the most important working environments that require optimal performance of individuals to minimize errors. Lighting is one of the environmental factors affecting the operation of the control room operators. Providing optimal lighting in the control room is very important. The purpose of this study was to determine the effect of light on workload, sleepiness, eye fatigue, and satisfaction of individuals from light conditions.

Material and Method: This was an interventional study conducted in a control room of a power plant. Intervention in the control room lighting was performed with two lighting systems including fluorescent lamps (4000 Kelvin, 200 lux) and LED lamps (4,000 Kelvin, 400 lux). Sixteen operators were evaluated under the two lighting systems in terms of workload, sleepiness, eye fatigue and satisfaction of individuals from light conditions.

Result: According to the results, eye fatigue significantly decreased after intervention (p (0.004>. Also, the higher light intensity, significantly decreased the level of sleepiness (p <0.001). In the study of workload, the amount of mental workload (p <0.001) and effort (p <0.03) decreased significantly, after intervention and the increase in the intensity of light; but physical demand, temporal demand, performance and frustration had no significant difference with the results before intervention.

Conclusion: In general, a combination of fluorescent and LED lighting systems, with 400 lux intensity, can provide optimal functional and mental conditions for control room operators. The illumination intensity of 400 lux in terms of workload, sleepiness, eye fatigue and the degree of satisfaction of individuals from light conditions provides a much better environmental condition than 200 lux.


Shahram Vosoughi, Mohammad Hossein Chalak, Sajjad Rostamzadeh, Manouchehr Jahanpanah, Hossein Ebrahimi,
Volume 10, Issue 2 (5-2020)
Abstract

Introduction: Fall from height is one of the main causes of death in the construction workers. Therefore, this study aimed to identify and prioritize the factors affecting falls from height accidents in construction industry.
Material and method: A descriptive-analytical study was conducted on five constructional projects in Pars Jonoobi industrial region, Iran. All of the reported events from 2011 to 2015 were investigated and 74 out of 377 occupational accidents were considered as falls from height accidents. The identified factors and sub-factors were divided into 3 main factors including individual, organizational and environmental factors and 14 sub-factors based on the experts’ opinion. Then, AHP method was used to determine and prioritize of the factors and sub-factors.
Results: The results of hierarchical analysis of fall from height accidents causes showed that environmental, individual, and organizational factors with weights of 0.359, 0.351, and 0.290 were in the first, second, third priorities, respectively. Meanwhile, among all examined sub-factors, work platform elevation, mental/ occupational stresses and safety culture had the highest priority.
Conclusion: Paying attention to the strategies that enhance the safety culture of employees and reduce their occupational stress levels in the workplace can be very effective in preventing of fall from height accidents.

Shahram Vosoughi, Kourosh Sarvari, Mohammad Hossein Chalak, Mohammad Khandan, Sajjad Rostamzadeh,
Volume 10, Issue 3 (8-2020)
Abstract

Introduction: Safety is a significant part of the public transportation. Suitable safety climate has a positive effect on safety performance and reduces accidents rate. The aim of this study was investigating safety climate status of Tehran subway drivers in 2013.
Material and method:  The present study was a descriptive and cross-sectional study. In this study, statistical population was all drivers of 1, 2 and 4 lines of Tehran Urban & Suburban Railway Operation company. Also, a questionnaire arranged by one of our researcher was used to collect demographics data of subjects. Safety climate was also investigated using standard Vinod Kumar's questionnaire. Data were analyzed by descriptive statistics and T-Student and ANOVA tests using SPSS21 software.
Results: Overall, 293 questionnaires were analyzed. Among the participants, 38.8% were line 1 derivers, 31.1% line 2 drivers and 33.1% line 4 drivers. The mean and standard deviation of the safety climate was 146.53±49.44, which is less than 147 (median). The results indicated that safety climate had a relation with the age group and education levels (P<0.01), while had no significant relationship with the deriving experience, and also marital status (P>0.05).
Conclusion: Safety climate status among subway drivers is not desirable. Among the various factors, commitment and performance of management in the safety area had the weakest status. Strengthening the structure of the health, Safety and Environment (HSE) management system in the Tehran Urban and Suburban Railway Operation company can enhance the level of safety climate among staff of this organization.
Gholamreza Moradi, Sana Mohammadi, Abdolrasoul Safaiyan, Saeid Ahmadi, Mehrnia Lak,
Volume 14, Issue 1 (3-2024)
Abstract

Introduction: Disturbing noise can cause physical and mental illnesses among workers; for this reason, it is necessary to restrain it, especially in workplaces. Using sound-absorbing materials with suitable acoustic properties has been a growing trend in mitigating noise. This study aimed to improve the acoustic properties of polyurethane foam (PUF) as a sound absorber.
Material and Methods: In the present study, PUF was synthesized with different percentages of clay nanoparticles (0 -1.2 wt.%), and then the Sound Absorption Coefficient (SAC) of the synthesized PUF was measured by the acoustic impedance tube in the frequency range of 63 to 6400 Hz according to the ISIRI 9803 standard without an air gap behind the sample. The morphology of the foam was also investigated by Scanning Electron Microscope (SEM).
Results: The results showed that the addition of clay nanoparticles to PUF improved the sound absorption behavior of the samples, and the best sound absorption behavior was for PUF with 1.2% weight of nanoparticles at low frequencies (500-2600 Hz). This increase in the absorption coefficient can be due to the increase in the number and smaller size of the pores with the increase in the amount of nanoparticles in PUF.
Conclusion: This study illustrates that the incorporation of clay nanoparticles into PUF at varying percentages results in an enhanced absorption coefficient. The presence of clay nanoparticles leads to a reduction in cell size and an increase in the number of pores, consequently enhancing surface friction. The absorption coefficient was observed to increase with the growing concentration of clay nanoparticles in PUF.
 
Abbas Bahrami, Hossein Akbari, Mahdi Malakoutikhah,
Volume 14, Issue 3 (10-2024)
Abstract

Introduction: Given the importance of the employment status of graduates for countries, the current study aims to investigate the employment status of occupational health and safety engineering (OHS) graduates from Kashan University of Medical Sciences (KAUMS), from the establishment of the field in 1996 up until 2023
Material and Methods: The cross-sectional study examined the employment status of OHS graduates of KAUMS using a researcher-developed Google form questionnaire. The questionnaire included demographic characteristics, five questions for unemployed individuals, and 60 questions for employed individuals. Finally, descriptive and analytical analyses of the study were performed using SPSS v16 software. 
Results: A total of 229 graduates participated in this study. The results regarding the frequency of employed and unemployed participants showed that 198 (86.5%) participants were employed, and 31 (13.5%) were unemployed at the time of the study. Most employed participants (46%, or 90 individuals) work in the industry and mining sector. Evaluating the effectiveness of the educational course of employed participants in relation to their jobs revealed that 88 participants (44.4%) believe that the subjects taught in the courses are moderately compatible with work needs. 
Conclusion: With the advancement of industries and the expansion of production, the need to control harmful factors and improve workers’ health is more evident than ever before, making it likely that graduates of this field will have favorable job prospects in the future. On the other hand, the academic conditions should be improved, particularly regarding the quality of the educational and curriculum programs of KAUMS. 
 

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