Showing 5 results for Hesam
Ghasem Hesam, Mohsen Aliabadi, Maryam Farhadian, Vahid Afshari Doust,
Volume 1, Issue 2 (Journal of Ergonomics 2013)
Abstract
Background: The use of visual monitors especially in relation to computer can cause health effects which have negative impacts on mental and physical performance of users. This study aims to determine the relation between ergonomic conditions in use of visual monitors and subjective feeling of fatigue in master science students as permanent users.
Methods: In this study, 40 students in the Hamadan University of Medical Scienceswere selected based onsimplerandomapproach. For determining subjective feeling of fatigue, the standard questionnaire with reliability coefficient equal to 0.8 was distributed and completed among students. This questionnaire has 30 questions which was covered three criteria included drowsiness, difficulty of concentration and physical impairment. The data about environmental and ergonomic conditions of the workstations was also recorded. Exposure to electromagnetic radiation in very low frequency was measured using instrument model HI 3603 front of the studied monitors. Data was analyzed with SPSS 16 software.
Results: The results showed mean score of drowsiness, difficulty of concentration and physical impairment were 17.8±6.5, 18.7±4.4 and 11.9±6.9, respectively. Totally, mean score feeling of fatigue was 48.5±15.7. The relation between continuous work time and feeling of fatigue was significant (P<0.05).The relation between work day time and feeling of fatigue was not significant (P>0.05). The relation between type of used monitor and feeling of fatigue was significant (P<0.05). Moreover, the relation between environmental conditions of the workstations and feeling of fatigue was not significant (P>0.05). However, descriptive results showed growing trend of feeling of fatigue in unsuitable environmental and ergonomic conditions. Moreover, exposure to electromagnetic radiation between to type monitors was statistically difference (P<0.05).
Conclusion: Criterion of difficulty of concentration was allocated the maximum score of feeling of fatigue which can cause negative impacts on educational performance. Compliance with the ergonomic principles especially reduction continuous work time and use of updated monitors and optimization of lighting and acoustic conditions of the workstations can reduce feeling of fatigue among students, considerably.
Ghasem Hesam, Majid Motamedzade, Ghasem Khakbaz, Zahra Moradpour,
Volume 2, Issue 2 (Journal of Ergonomics 2014)
Abstract
Introduction: Musculoskeletal disorders are the most common occupational diseases and injuries. The importance of control and reduction the discomfort to the extent that in many countries, Prevention of work-related musculoskeletal disorders among workers has been considered as one of the national priorities.
Methods: the cross-sectional study was carried out as an intervention in a chicken slaughterhouse. In order to determine the prevalence of musculoskeletal disorders, Cornell questionnaire was used. By identifying the tasks that are very high in musculoskeletal disorders posture evaluate was conducted and then the proportional to risk level tasks, engineering and management measures was performed. Given that most tasks are the kind of manual handling and carrying, were used the KIM methods for evaluating posture before and after of intervention.
Results: The results of the Cornell questionnaire showed that the highest risk level Belongs to the neck, shoulders, back, arms and waist. Also evaluate by the KIM method the highest level of risk was estimated, the task of throwing the box and pick up the ice with the risk level 4 score, that after the intervention, decreased to the 2 score. Improvement obtained for all interventions on the average about 46.37 percent. The McNemar test was also significant difference between the results obtained before and after intervention.
Conclusion: ergonomic problems have undesirable effects on employee health and productivity. This study, engineering and management interventions could significantly reduce the amount of corrective measures to improve working conditions in different parts of the company.
Majid Motamedzade, Zahra Moradpour, Hamed Gorjizade, Ghasem Hesam, Abbas Moghim Beigi,
Volume 2, Issue 4 (Journal of Ergonomics 2015)
Abstract
Introduction: The analysis posture methods are counted as a source of investigating the risk of musculoskeletal disorders related to work. Personal digital assistant is a small mobile system with an operative system that can install on various programs such as posture analysis methods.
Method: Firstly, three ways for posture analysis such as QEC, RULA and REBA determined. Afterward, the program of posture analysis methods written by BASCOM software with Basic language in IC MICRO CONTROLLER belong to AVR family, and interned in IC by programmer for making PDA. PDA Usability evaluated by Persian version of system usability scale questionnaire after specifying the validity and reliability of questionnaire. Finally, postural analysis was compared using a PDA with paper method.
Results: The system usability scale of PDA method is 84.2±6.2 which that got B rank and placed in very well situation. Cronbach's Alpha and Pierson correlation coefficient belongs to System usability Scale are 0.716 and 0.888, sequentially (p˂0.001). The comparison between PDA and paper methods show us that time’s operation for analysis posture in PDA method is less than half of the time in papers method. Also, the probability of calculation errors in PDA is zero, but in paper method has tolerance between 2.33 to 8.66.
Conclusion: Use of personal digital assistant for analysis posture solved the problems related to delay achieving to final results and removed the error probability in final results.
Amir Aliabadi, Ghasem Hesam, Zahra Moradpoor,
Volume 2, Issue 4 (Journal of Ergonomics 2015)
Abstract
Introduction: Welding is
considered to be one of the main sources of occupational exposure to non
ionizing radiations. The present study was conducted to examine the rate of
occupational exposure to non-ionizing radiation in common welding processes.
Materials and
Methods: In the present descriptive analytical study, occupational
exposure to different types of non-ionizing radiations including
electromagnetic fields with extremely low frequency and ultraviolet and
infrared radiations were examined in five types of arc welding processes at the
welding department of the technical and vocational training center of Malayer.
Electric field intensities and magnetic field intensities were measured using
the HOLADAY HI-3604 instrument and based on the ANSI/IEEE Std 644-1994 method. Ultraviolet and infrared radiation intensities
were measured using Hagner-EC1 radiometer (made in Sweden).
Results: Electric
field intensities and magnetic field intensities were lower than the exposure
limits in the different types of welding processes examined. Nevertheless, the
intensity of UV-B radiation
exposure was higher than the exposure limits in the different types of welding
processes examined, while UV-A radiation exposure was only higher than the
exposure limits in arc welding. The results of measuring UV radiation
intensities transmitted through protective goggles revealed the acceptable
shade number of the lenses used. However, welders' clothing did not provide
adequate protection. Moreover, the results showed that welders' infrared
radiation exposure degree was much lower than the exposure limits.
Conclusion: The intensity
of exposure to non-ionizing radiations was influenced by the type of welding
process taken. Given the overexposure of welders to UV-B radiation in unshielded conditions, wearing clothes with
an Ultraviolet Protection Factor of 50 is necessary for providing better
protection.
Sajjad Farhadi, Ghasem Hesam, Zahra Moradpour, Malek Abazari, Yousef Babayi Mesdaraghi,
Volume 4, Issue 2 (Journal of Ergonomics 2016)
Abstract
Introduction: Firefighting is amongst jobs that require high physical strength and high aerobic capacity. These are required because of the nature and the physical demands of the job. The maximum aerobic capacities of firefighters were investigated using the step test.
Methods: This cross-sectional descriptive-analytical study was conducted on 73 firefighters. At first, demographic information was collected by a questionnaire. Then, the step was built with adjustable height, for step testing, and using the Francis method, maximum aerobic capacity of the participants, was studied. The results of the questionnaire and step test were analyzed by the SPSS 16 software.
Results: maximum aerobic capacity of firefighters was calculated as 3.65 L/min and 47.4 mL/kgmin. Moreover, the results of statistical analysis revealed a significant relationship between body mass index and exercise, and maximum aerobic capacity (P ˂ 0.05). Also no significant relationship was found between maximum aerobic capacity, age, smoking and work-related fatigue (P > 0.05).
Conclusions: Studying the firefighters cardiorespiratory capacity, to reduce the probability of firefighters injuries is very important due to occupational sensitivity and having to perform difficult tasks under demanding circumstances. 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, which can be due to regular physical fitness programs conducted by the organization.
