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Introduction: Exposure to noise and heat causes individuals to experience some changes in the function of cardiovascular system in workplaces. This study aimed to find the combined effect of heat and noise on systolic and diastolic types of blood pressure in experimentally controlled conditions., Methods: This quasi-experimental study was performed with 12 male students in a climatic chamber in 2014. Blood pressure including systolic and diastolic was measured in the following conditions: 15 min after rest in exposure to heat (40°C, relative humidity [RH]: 30%), exposure to noise with 75, 85, and 95 dB rates in thermal comfort condition (22.1 ± 0.9 wet-bulb globe temperature), and combined exposure to heat (40°C, RH: 30%) and noise with 75, 85, and 95 dB. Friedman test was used to analyze the data., Results: The mean change of systolic blood pressure was different significantly before and after exposure to heat and noise levels including 75, 85, and 95 dB ( P = 0.015, P = 0.001, P > 0.001, P = 0.027, respectively). Although systolic and diastolic blood pressures changed drastically, it was not significantly different in simultaneous exposure to heat and noise., Conclusion: Both systolic and diastolic blood pressures decreased in exposure to heat, while exposure to different levels of noise elevates systolic and diastolic blood pressures. However, when exposed to a combination of heat and noise, subtle changes of blood pressure were traced, which can be characterized as average, considering heat-only and noise-only tension situations., Competing Interests: There are no conflicts of interest.

Background: Heat stress is a threat to those who work in high temperatures. The purpose in this study was an examination of the cooling ability of Iranian phase change material (PCM) cold vest in hot and dry conditions in a climatic chamber., Materials and Methods: This experimental study was implemented on 12 male students (age 23.7 ± 2.8 years, weight 66.1 ± 11.4 kg, and VO2 max 2.53 L/min) in 2013. The heat strain score index (HSSI), skin temperature and oral temperature, and heartbeat in two phases with and without cooling vest was measured during 30 min in a climatic chamber (temperature 38.8 ± 1.3°C humidity ratio 32.9 ± 2.3%) and in two activity intensity of 2.4 and 4.8 km/h speed on the treadmill, and the data differences between groups "with" and "without" vest were tested by t-test and repeated measurement. The level of significance was considered as 0.05., Results: The change in heartbeat at two activities, the oral temperature and heat strain score at 4.8 km/h, did not differ significantly between groups (with and without vest), as expected (P > 0.05). However, the change in skin temperature at two activities, oral temperature and heat strain score at 2.4 km/h, was significant between groups, as expected (P < 0.05). The average of skin temperature at 15(th) and 30(th) min during the experiment at two activities of 2.4 and 4.8 km/h was significant., Conclusion: The findings of the study indicated that using the Iranian PCM cold vest in hot and dry climate can affect the reduction of skin temperature, oral temperature, and HSSI in light activities.

Context: Fatigue is a factor that can have negative effects on family life, social relationship and work. Work schedule is one of the affective factors on personnel's fatigue in different jobs. In this study, the work schedule and its effect on rescue personnel in Isfahan are explored., Aims: The purpose of this study was to investigate the relationship between work schedules and fatigue among rescue personnel., Settings and Design: This study is periodical and has been conducted on 72 employees of rescue personnel in Isfahan., Materials and Methods: Random sampling was done and the primary data that was collected through fatigue assessment questionnaire after being conducted as a pilot study on 10% of samples were collected to confirm the validity of this study. Finally, the data was given to SPSS11.5 software and were analyzed by descriptive statistics and linear digression., Results: The results showed that from the statistical point of view some parts of work schedules like work hours satisfaction, resting time and work order on total fatigue are effective in linear and inverse way but the item "predictibility of work conditions" does not have a meaningful relationship with total fatigue. Furthermore, the results showed that there is a meaningful and inverse relationship with work hours, resting time and work order with mental fatigue and also the work schedule has a meaningful, linear and inverse relation with mental fatigue and total fatigue., Conclusions: By increasing the satisfaction of working hours, increasing resting time and also with an increase of work order the total fatigue of rescue personnel will decrease.

Background and Objective: To establish a balance between work (physical exercise) and human beings, the aerobic capacity (VO2 max) could be used as a measure. Additionally, the subjective and physiological assessment could be applied as one of the methods for assessing physical exercise. The most commonly used tools for the assessment of fatigue during physical exercise include the Borg scale Rating of perceived Exertion (RPE) in relation to subjective symptoms and heart rate (HR) in relation to physiological symptoms. The study is aimed to investigate the relationship between the aerobic capacity and the RPE based on the measurement of heat rate (HR) of workers from the Metal Industries of Isfahan., Materials and Methods: The subjects were 200 male workers from metal components manufacturers in Isfahan selected by using random sampling based on statistic method. The subjects were examined by using ergometer in accordance with A strand 6 minutes cycle test protocol. Furthermore, the subjects were asked to rate their status based on the Borg rating scale at the end of each minute. Additionally, their heat rates were monitored and recorded automatically at the end of each minutes., Results: Statistical analysis showed that there was a significant relationship between the RPE and the aerobic capacity (VO2 max) (r = -0.904, P < 0.05). The results illustrated that there was a stronger correlation between HR and VO2 max (r = 0.991, P < 0.001). The regression analysis of the quadratic equation also indicated that there was also a significant relationship between the VO2 max and HR., Conclusions: The results indicated that there was a strong relationship between the RPE and VO2 max, as well as a greater correlation between HR and VO2 max. Therefore, the HR could be used as a Prediction measure to estimate VO2 max.

Unlabelled: Psychological problems as state anxiety (SA) in the work environment has negative effect on the employees life especially shift work nurses, i.e. negative effect on mental and physical health (sleep quality, eye fatigue and comfort thermal). The purpose of this study was determination of effects of state anxiety and thermal comfort on sleep quality and eye fatigue in shift work nurses., Methods: This cross-sectional research conducted on 82 shift-work personnel of 18 nursing workstations of Isfahan hospitals in 2012. To measure the SA, sleep quality, visual fatigue and thermal comfort, Spielberger state-trait anxiety inventory, Pittsburg sleep quality index, eye fatigue questionnaire and thermal comfort questionnaire were used respectively. The data were analyzed with descriptive statistics, student test and correlation analysis., Results: Correlation between SA and sleep quality was -0.664(P < 0001), Pearson correlation between SA and thermal comfort was -0.276(P = 0.016) and between SA and eye fatigue was 0.57 (P < 0001)., Conclusion: Based on these results, it can be concluded that improvement of thermal conditions and reduce state anxiety level can be reduce eye fatigue and increase the sleep quality in shift work nurses.

Introduction: Work-related stress is one of the basic problems in industrial also top 10 work-related health problems and it is increasingly implicated in the development a number of problems such as cardiovascular disease, musculoskeletal diseases, early retirement to employees. On the other hand, early retirement to employees from the workplace has increased on the problems of today's industries. Hereof, improving work ability is one of the most effective ways to enhance the ability and preventing disability and early retirement. The aim of This study is determine the relationship between job stress score and work ability index (WAI) at the refinery workers., Materials and Methods: This is a cross-sectional study in which 171 workers from a refinery in isfahan in 2012 who were working in different occupational groups participated. Based on appropriate assignment sampling, 33 office workers, 69 operational workers, and 69 maintenance workers, respectively, were invited to participate in this study. Two questionnaires including work related-stress and WAI were filled in. Finally, the information was analyzed using the SPSS-20 and statistic tests namely, analysis of covariance Kruskal-Wallis test. Pearson correlation coefficient, ANOVA and t-test., Results: Data analysis revealed that 86% and 14% of participants had moderate and severe stress respectively. Average score of stress and standard deviation was 158.7 ± 17.3 that was in extreme stress range. Average score and standard deviation of WAI questionnaire were 37.18 and 3.86 respectively. That placed in a good range. Pearson correlation coefficient showed that WAI score had significant reversed relationship with a score of stress., Conclusion: According to the results, mean stress score among refinery worker was high and one fator that affect work abiity was high stress, hence training on communication skills and safe working environment in order to decreses stress, enhance the work ability of workers.

Background: In the hot weather, overweight and obesity are considered as significant risk factors for the incidence of cardiac strain in workers. This study is aimed at comparing the cardiac strain among overweight and normal-weighted workers, in the hot, humid conditions of the south of Iran., Materials and Methods: This cross-sectional study was conducted on 71 workers in the south of Iran, in the summer of 2010. The heart rate was measured at rest and at actual work. Cardiac strain based on the working heart rate (WHR), the relative cardiac cost (RCC), the net cardiac cost (NCC), the load relative cardiovascular (CVL), and heart rate reduction were analyzed in 35 normal weight people (BMI <25) and 36 people who were overweight (BMI >25), using descriptive statistics and t- tests., Results: In 42% of the total workers, the body mass index was more than 25. The average temperature of the two groups was not significantly different. The mean WHR in these two groups was 101 ± 20.3 and 112 ± 18.9, respectively (P = 0.026). Percentages that exceeded the acceptable limits in parameters of NCC, RCC, WHR, CVL, and the Brouha index, were significantly higher in overweight people than those in people with normal weight., Conclusions: Based on the study results, the severity of cardiac strain was higher in overweight workers when compared with normal weight workers. Hence, in order to decrease the cardiac strain, selecting overweight individuals for these jobs should be avoided, as also some vital intervention for losing weight, such as, nutrition education and encouraging them to increase their physical activity, should be implemented.