نشریه طب کار
سال پنجم شماره 1 (پیاپی 10، بهار 1392)

Fatigue is an important inhibiting factor in human performance، so with rising aerobic power could be overcome individual fatigue. Based on the importance of maximum oxygen consumption at fatigue threshold، the purpose of this study was to evaluate changes in temperature of the maximum rate of oxygen consumption and time to exhaustion in workers of spinning factory. In this quasi-experimental study، maximum rate of oxygen consumption in 30 participants in three series was measured: A) Before running Strand and Kankany step test at the temperature of 25 ° c، B) After running Astrand and Kankany step test the temperature of 25 ° c and C) 48 hours later، at the temperature of 40 ° c. For data analysis SPSS (version18) was used. Results indicated that the mean maximum oxygen consumption in Astrand step test in temperature of 25 ° c and 40 °c was 55. 1±6. 2 and 50. 8±5. 6 respectively، and for Kankany test was 31. 2±1. 8 (25 ° c) and 30. 4±0. 81 (40 ° c). Therefore there were significant difference between heart rate average، maximum rate of oxygen consumption and amount of work done in two different temperatures in Strand step test (p<0/05)، Also in Kankany test، significant difference observed between average of heart rate and the amount of work done at the two temperatures (p <0/05)، but there was no significant difference between the maximum oxygen consumption at two temperatures. The overall results of this study showed at temperature of 40 ° c، the maximum rate of oxygen consumption was less than 25 ° c. In other word، in higher temperatures، the maximum rate of oxygen consumption was decreased.

Noise-induced hearing loss is a sensorineural hearing loss، which is associated with exposure to high levels of sound. Since train drivers exposed to high noise levels and the use of hearing protection devices is relatively difficult and they also need to hear the radio communications، this study examines the hearing status of train drivers of Yazd Railway Company.

This is a descriptive - analytical cross sectional study، which was performed on 153 train drivers. The results were compared with a control group of 148 office workers. After examination and blood tests، audiometry was performed for each subject by an audiologist and the data was analysis with SPSS software (ver. 19).

The mean age of the train drivers and control group were 35. 8±8. 3 and 35. 3±6. 3 years respectively. Prevalence of high frequency sensorineural hearing loss among train drivers was 21. 3% (29 patients)، that was significantly higher than the control group. Prevalence of high frequency notch in the right ear in train drivers was 9. 6% (13 patients) and 2. 9% (4 patients) in the control group (p-value <0. 02) and prevalence of notch in left ear was 14% (19 patients) and، 3. 7% (5 persons) in train drivers and control group respectively (p-value<0. 003). In train drivers average hearing thresholds of high frequencies was higher in the left ear than the right ear (p-value=0. 02).

The high level of noise in the train drivers'' cabin increases average hearing thresholds at high frequencies especially at 6000 Hz. The results also show that in noisy environment، left ear is more sensitive than the right ear.

Radiology tests are used to diagnose a variety of diseases. Performing such examinations has potential risks for patients and radiographers working in radiology departments. These risks can be minimized by compliance with safety practices. The aim of this study was to assess the knowledge، attitude، and practice of radiographers working in the radiology departments of Yazd about the new guidelines on radiation protection. A cross-sectional descriptive and analytic study was done using a 38 item questionnaire among all of 112 radiographers working in the radiology departments of Yazd Province. The data of completed questionnaire was analyzed by non-parametric tests and Spearman correlation coefficient using SPSS software. Participation rate for radiographers was 69. 6%. The average and standard deviation scores of knowledge، attitude and practice in the field of radiation protection were 46. 50±15. 30، 78. 33±12. 53، and 45. 90±16. 78، respectively. There was a significant inverse relationship between age and experience (years of practice) and knowledge of radiographers (P<0. 05). There was also a significant relationship between education and knowledge of radiographers. Results of this research showed that the amount of knowledge of radiographers in the field of radiation protection was decreased with increasing age and experience. Also، depending on the degree of their knowledge، there was a statistically significant difference in awareness. For solving this problem، the retraining courses contain new guidelines relating to radiation protection should be conducted.

occupational stress identified as imbalance between occupational needs with individual’s abilities & demands. Occupational stress has somatic، psychological and behavioral effects. It seems that medical students have more severe degrees of occupational stress because of long period of education and mandatory presence in clinical and hospital environment. The goal of this study was evaluate of occupational stress and influencing factor in medical students of Iran University of medical science in two major categories of basic science and clinical medicine. A cross-sectional survey was conducted on 516 medical students with history of at least 3 months of medical education in 2010. Evaluation of occupational stress was conducted using osipow questionnaire (ά=0. 83). From 650 students that entered the study، 516 student answered to questionnaire (response rate=80%). The average of stress score is 132 in basic science and 157 in clinical group. We have increasing total stress scores in students with higher education levels. Stress in older students was higher than younger students. Also، Stress was higher in smokers’ students and who have history use of sedative drugs. The stress was increased significantly based on educational years. According to higher levels of total stress score in students with higher levels of education، establishment of stress management courses in faculty of medicine and familiarization of medical students with occupational stress and coping methods may be useful for modification of occupational stress in these students

Lack of anthropometric data in designing work stations، tools and equipment، could be resulted in work related injuries. Therefore، creating anthropometric data bank is essential. The aim of this study was to present anthropometric data from Fars workers and also determining the regression equations between these dimensions and stature as a reference dimension. A total of 539 Fars workers aged 18-60 from factories which are in 3 provinces participated in this descriptive and cross sectional study. Thirty-seven body dimensions were measured in standard positions presented by Kroemer guidelines، and data were analyzed in SPSS version 18. Mann-Whitney test was used in order to compare measured dimensions between men and women. Moreover، in determination of correlation among anthropometric dimensions، Linear Regression analysis was made. According to the results، the mean stature of women and men were 158/35 (±6/59) and 172/98 (±6/69) respectively. In relation to stature and other body dimensions، a significant difference were observed between men and women (P value 0<0/05). According to the Linear Regressions analysis، heights of eye، shoulder and elbow in standing positions and grip reach in standing position were significantly correlated with stature (P value 0<0/01). Significant differences were observed between women and men body dimensions. Furthermore، comparison of stature in the present study with other similar studies has shown a difference that may be due to differences in ethnicity of selected samples. Furthermore، the estimated regression equations can be used in predicting some of the anthropometric dimensions.

Lead is one of the most toxic heavy metal which its toxicity and poisoning symptoms in workers of different industries (such as battery industry due to heavy use) is completely known. Important effects of this toxic metal are paralyzed wrist (nerve effects) as well as bone disease. The scope of this study is to evaluate the occupational exposure of workers of a battery industry to these pollutants. In this study the exposure to lead metal was evaluated. Twenty four workers were selected as the exposed group and breathing zone air samples were taken from them. For sampling of particulates، sampling pump model SKC made in UK and cellulose ester membrane filter with 0. 8-μm pore size، and 37 mm diameter were used. The whole sampling process and analysis of samples were performed according to the 7300 NIOSH method. The pump flow set to 2 L/min and the filter was fixed to the collar of worker by cassette filter holder. After sampling، the filters transferred to the laboratory and were digested in the mixtures of HNo3 and HCLo4. Then، they analyzed by ICP-AES instrument. The results are analyzed using SPSS18 with T-test and showed that 9 stations of 12 stations have higher results than mean average exposure to lead in this plant (75% of total sample)، and the results of ELBACK station were more than others. The T-TEST showed a higher mean average exposure to lead in this plant. (Mean= 0. 33mg/m3 S. D =0. 48; P Value= 0. 008) The findings showed that health status of workers in these industries is at risk due to unauthorized amounts of this toxic metal. To reduce occupational exposure، using appropriate engineering controls (air conditioning)، administrative management (eg reducing exposure time) are necessary.

Provide a review of occupational medicine history in world and Iran Many books، papers and sites on the occupational medicine history were reviewed. Occupational medicine have been shaped by the forces that shape work itself، social evolution، changing modes of production، shifting economic powers، and demographic changes in the workforce. Hippocrates emphasized the relation between environment and health، although he has less to say about the non-military work environment. The impact of work on health could be traced to the Edwin Smith Surgical Papyrus، written approximately 1700 BC. The earliest occupational physicians served military forces، and Galen was physician to Roman gladiators. Finger and wrist guards worn by Bronze Age archers represent early Personal Protective Equipment (PPE). Writers mention diseases and hazards of miners، and Pliny (1st century AD) mentions veils to cover the face. Paracelsus and Agricola were prominent، figures in the 15th century، with an emphasis on mining and health. Ramazzini''s (c1700) work was widely translated in ensuing decades and is now well-known to all. In Iran، Rhazes included occupation in his case studies (9th century). Many other men like Avicenna، Jorjani، and others conducted many works and wrote many books about occupational and environmental medicine. The emergence of a public health movement in the mid-1800s focused attention on the abominable conditions of many factories and on the living conditions، poor nutrition، high stress، poverty and ill health of the new factory working class، while paying scant attention to specific workplace hazards.