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Background and purpose : Respirators (respiratory protective equipments) are widely used, but many of their health impacts, especially cardiovascular effects, have not been determined. The aim of this study was to determine the impact of using respirators on heart rate, systolic and diastolic blood pressure.
Materials and methods : This interventional study was undertaken on 40 healthy 20-30 years old young men. Their heart rate, systolic and diastolic blood pressure at rest and at the end of 5 minutes 7kcal/min exertion with ergometer were measured. Âfter 15 minutes rest, this process was repeated, while the person was breathing via respirators. The data were analyzed using SPSS, descriptive statistics and paired t-test.
Results : Üsing respirator during heavy work increased the mean value of heart rate to 8.5 beat/min, systolic and diastolic blood pressure 7.4 and 4.9 mmHg respectively.
Çonclusion : This study showed that respirator imposes additional load on cardiovascular system. Âlthough these increases may seem inconsiderable, these mild increases of heart rate and blood pressure can be threatening in workers with hypertension, coronary artery disease and many other cardiovascular disorders

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Background and purpose: Noise is one of the most harmful factors in the environment. It is also one of the harsh phenomenons in this century that people are exposed to. Exposure to noise higher than threshold limit value could cause some physical and mental disorders. High traffic flow due to recent increase in number of vehicles causes higher noise pollution. There are few studies regarding the evaluation of noise pollution in the environment in some Iranian cities. Thus, it is necessary to measure sound pressure level and other related parameters for noise pollution control. Identification of the effective factors on noise pollution is the best approach for promotion of individual, as well as, public health and safety. The aim of this study is to evaluate the noise level in the city of Sari.
Materials and methods: There exist various methods for calculating the equivalent noise level regarding to noise measurement period. The most ordinary method is DL (day average sound level), that takes 15 hours of sampling (7 am- 10 pm), based on regulations that was approved by the National Environmental Protection Association in year 2003. This method was used for evaluation of noise level in this study. In the first stage, sampling locations were selected, followed by measuring sound levels at the height of one’s hearing zone (1.6 m above the ground surface). A calibrated sound level meter (Model Cell-490, Casella CEL, England) was used for all measurements. The SPSS software V.15 was used to perform T-test analysis.
Results: The results showed that the mean (SD) DL was 75.52± (4.41) dB. The minimum and maximum sound pressure levels during the sampling period were 47 dB and 121.5 dB respectively. Due to the measurement of various circumstances, some times, and also, sampling locations, measure sound pressure level was high.
Conclusion: The mean sound level during the daytime period was higher than the national standard levels. Therefore, environmental noise control is the best approach for the prevention of noise related to adverse health effects.

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Background and purpose: High concentrations of respirable particles in both the outdoor and indoor environments are associated with adverse health effects that could reduce the performance of students. This study was carried out to investigate the indoor concentrations of respirable particle and outdoor concentrations of PM2.5 at classrooms in primary schools in Sari, north of Iran. We also evaluated the relationship between outdoor concentration of particles and other environmental factors. Materials and methods: Six primary schools located in Sari city center were selected. A size selective GRIMM particle monitor was used to measure the indoor classrooms continuous real-time particle distribution and a real time Micro Dust Pro monitor was used for outdoor measurement. Results: The maximum and minimum concentrations of indoor PM1 and PM2.5 were observed in spring and autumn, respectively. The highest level of PM10 was seen in winter. The mean indoor PM2.5 concentration in classrooms was (46.6 µgm-3) which was higher (P<0.05) than the mean outdoor PM2.5 concentration (36.9 µgm-3). Ambient temperature had a significant negative effect on indoor PM2.5 levels. Conclusion: Resuspension of indoor particles and replacement of indoor and outdoor air are amongst the most effective determinants for indoor particle concentrations.

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Background and purpose: This study aimed at estimating the relationship between air pollution and mortality rate due to cardiovascular diseases (CVD) in Mashhad, Iran 2011, using negative binomial regression.

Materials and methods: The dataset of mortality rates due to CVD and different types of these diseases in Mashhad were coded according to ICD 10. The dependent variable was the logaritm of the daily cardiovascular mortality. Independent variables and air pollutants were also determined. The effect of different factors and the estimation of the incidence rate ratio was done with one day lag time. Data analysis was performed in Stata software.

Results: Negative binomial regression analysis showed a significant association between the increase in air pollutants and the cardiovascular mortality. By increase in air pollutant variables including CO, SO₂ , NO_X, NO₂, and  NO  the incidence rate ratio had increased by 1.23 CI:(1.10,1.37), 1.03 CI:(1.01,1.05), 1.001 CI:(1.001,1.003), 1.01 CI:( 1.006,1.014), and 1.002 CI:(1.001,1.003), respectively. No significant relationship was found between the PM₁₀ and PM_2.5 and the incidence rate of cardiovascular death. Increase in O₃ had an inverse impact on the increase of mortality incidence rate 0.98 CI:(0.97,0.99).

Conclusion: Among the air pollutants, CO had the highest effect on CVD death and O₃ had a significant inverse impact on CVD mortality rate.

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Background and purpose: Air pollution causes respiratory diseases such as chronic obstructive pulmonary disease (COPD). In this study we aimed at statistical modeling of the effects of air pollution on mortality due to chronic pulmonary disease and COPD in Mashhad, Iran, using negative binomial regression.
Materials and methods: Mortality data due to chronic pulmonary diseases and the average amount of air pollutants per 24 hr were collected from 12 air pollution monitoring stations in Mashhad, 2011. Negative binomial regression was used as an appropriate statistical model to analyze discrete data.
Results: The effects of all pollutants, except PM particles and ozone particles, were found to have direct significant effect on mortality due to chronic pulmonary disease. The ratio of the incidence rate of mortality among patients with chronic pulmonary disease was highest for CO (IRR= 1.37, p<0.001), SO₂ (IRR= 1.04, p<0.001), NO₂ (IRR= 1.01, p<0.000), NO (IRR=1.003, p<0.000). But ozone had an inverse effect on chronic pulmonary mortality (IRR= 0.96, p<0.000).
Conclusion: Among the pollutants, CO had the highest effect and O₃ had a significant reverse effect on the rate of respiratory mortality. At the beginning of winter (January) we observed maximied rate of mortality and air pollution.
 

considered                                                                                                                                                                                                                                                                                                                                            

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Correction to: Relationship between Air Pollution and Mortality Rate due to Chronic Obstructive Pulmonary Diseases in Mashhad, Iran
 
 
Narges Ghorbani¹,
Jamshid Yazdani-Charati²,
 Siavash Etemadinejad³,
Nasrin Ghorbani^4
 
1 PhD Student in Biostatistics, Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
² Associate Professor, Department of Biostatistics, Health Sciences Research Center, Addiction Institute, Mazandaran University of Medical Sciences, Sari, Iran
³ Associate Professor, Department of Occupational Health and Ergonomics, Health Sciences Research Center , Mazandaran University of Medical Sciences, Sari, Iran
⁴ Medical Records Technician, Omid Hospital, Mashhad, Iran
 
 
    

In the article published in volume 28, issue 169, 2018, the affiliation for the corresponding author was published incorrectly, which is now corrected.
 

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Background and purpose: The design of medical equipment is a crucial aspect of ergonomics, with the proper fit of tools in the user's hand being a significant consideration in production. This study aims to investigate the level of discomfort experienced by surgeons due to the use of latex gloves in the year 2021, to enhance user satisfaction and reduce workplace injuries.
Materials and methods: This cross-sectional study was conducted on 135 surgeons in the city of Sari. The data collection tools included a questionnaire for measuring anthropometry in two dimensions and assessing local discomfort. The questionnaire consisted of 12 questions to evaluate discomfort levels in the hands. Two-dimensional anthropometry measured the dimensions of the participants' hands, presenting a 24-dimensional result.
Results: Overall, the various dimensions of anthropometry in male participants were larger than those in female participants, except for the second dimension. Male surgeons (52.1%) mostly used gloves size 7, while female surgeons (74.2%) preferred sizes 5/6. The lowest average pain level was recorded in Region B (1.24), and the highest average pain level was in Region I (2.43).
Conclusion: The study results indicated that women experience higher levels of discomfort compared to men. The areas with the highest discomfort levels were identified, and optimal dimensions for designing and producing suitable gloves for the study population were determined.