mahmoud mohammadyan

Particulate matter, as one of the biggest problems of air pollution in metropolises, is the cause of many respiratory, lung and cardiovascular diseases, which timely awareness and announcement can reduce these adverse effects on human health. Therefore, considering that children are more exposed and more sensitive to this pollution, this research was conducted to introduce an evaluated mathematical model to predict PM2.5 concentration levels, indoor selected preschools located in one of centeral district of Tehran (district 6), using determination of related factors to PM2.5 concentration. Classroom environmental information, Meteorological information and urban fixed monitoring stations data were collected through measuring Indoor and outdoor classroom PM2.5 concentrations using direct-reading instruments, adjusted questionnaire and conducted organizations, simultaneously. Results showed the spring and autumn had the lowest and highest indoor and outdoor concentrations (17.1 and 20.5 μg m-3 & 48.7 and 78 μg m-3respectively). Multiple linear regression model was introduced by statistical analysis and the results of indoor PM2.5 concentration predictions were compared and evaluated with measured data. The results of introduced this model, consisting of identifying seven main factors affecting the mean concentrations of indoor PM2.5, including outdoor PM2.5, the number of pupils, ambient temperature, wind speed, wind direction and open area of the doors and windows, showed that it has good accuracy (R2 = 0.705) and significantly correlated(p < 0.001). The Multiple Linear Regression Model can be used with good accuracy to predict indoor PM2.5 concentration of preschool classes in Tehran.

Workers' exposure to manganese fumes emitted from the welding Process can lead to various ranges of diseases. This study aimed to investigate the concentration of manganese fume in the respiratory area of workers working at an industrial shed manufacturing factory in Amol, Iran.

This descriptive-analytical and cross-sectional study was conducted on the welders working at an industrial shed manufacturing factory in Amol, Iran (case group; n=35) and employees of administrative departments (control group; n=35). Inhalable Particles concentration and manganese concentration in welding fumes were measured using the NIOSH-0600 and NIOSH-7300 standard methods, respectively. Data analysis was Performed by SPSS software (version 25) using descriptive (mean and standard deviation) and analytical statistical methods (chi-square test, Spearman's rank correlation coefficient, and regression testing).

The mean exposures of welders to inhalable Particles and manganese in welding fume were 2.4±1.2 and 0.15±0.83 mg/m3, respectively. The maximum and minimum concentrations of inhalable Particles and manganese in welding fumes were 6 and 0.36 mg/m3, as well as 0.7 and 0.04 mg/m3, resPectively. There was a significant relationship between average Particle concentration and manganese concentration in welding fume among the two groups of maximum and minimum exposure limits. Moreover, a significant association was observed between the concentration of inhalable Particles and the concentration of manganese in welding fumes (P<0.001).

The exposure of all welders to manganese welding fume exceeded the allowable limit. Therefore, technical, engineering, and management control measures are recommended to reduce exposure to manganese.

Manganese (Mn) is an essential element for the human body, but it can cause adverse effects on the Central Nervous System at high doses. Exposure to manganese fumes during welding can harm welders' health.

The current study aimed to measure manganese produced by shielded metal arc welding (SMAW) in the breathing zone air and blood of welders and investigate the relationship between manganese concentrations in air and blood.

In this descriptive-analytical cross-sectional study, 35 welders were enrolled as the exposed group and 40 office workers as the control group. Manganese concentration in air was measured according to NIOSH method 7301. Air and blood sample analyses were carried out by ICP-OES. Statistical analysis was performed with MINITAB 17. Data were analyzed using Pearson correlation coefficient, one-sample t-test, paired t-test, and logistic regression. The significance level was set at P < 0.05.

The mean concentration of welding respirable particles and manganese fumes were 9.56 ± 1.67 and 0.45 ± 0.08 mg/m3, three and 22 times the exposure limit recommended by ACGIH, respectively. Average manganese was significantly higher in the welders’ blood (0.16 ± 0.02 µg/mL) than in the controls’ blood (0.04 ± 0.002 µg/mL). There were strong and significant correlations between the welding respirable particles and manganese concentration in welders’ breathing zone and blood manganese levels. Also, with each year of work experience, the manganese concentration in the welders’ blood increased by 1.5%.

Welders are at risk of contamination with manganese. Manganese exposure reduction through more efficient ventilation systems, reducing welder’s exposure time, staff training, and appropriate respiratory protection equipment should be applied to reduce manganese exposure among welders and prevent health complications.

Cement factory workers exposure to airborne particles containing crystalline silica in Portland cement chemical compound can caused pulmonary diseases, including silicosis and lung cancer. The aim of this study was to assess the risk of occupational exposure to respirable cement dust and crystalline silica in a cement factory in Khorasan Razavi province.

In this cross-sectional study conducted in 1397, the method presented by the Institute of Occupational Safety and Health of Singapore was used to assess the health risk of respirable cement and silica particles. Also, the standard method MDHS101 / 2 recommended by NIOSH was used to determine the concentration of respirable cement particles in the air of the workerschr('39') respiratory area and the X-ray powder diffraction method (XRD) was used to determine the concentration of inhalable crystalline silica particles. Stata software version 14 was used for statistical analysis of data.

This study showed that most of the workers employed in various worksites of the cement factory were exposed to respirable cement dust and crystalline silica particles higher than the OEL recommended by the Iranian TCOH and the TLV recommended by ACGIH. Exposure risk assessment in different parts of cement factory showed a low risk level for respirable particles of cement in the furnace and moderate for other sections. Also a high risk level for workers’ exposure to crystalline silica was found in the cement mill and very high level for workers in other sectors.

Employees who were working in this plant were exposed to moderate risk of cement respirable particles and high risk level of exposure to crystalline silica. Thus, the engineering control methods of exposure to respirable particles is suggested.

BTEX is one of the most important pollutants in organic compounds in paint compounds, the toxic effects of which are well known. Therefore, the aim of this study was to health risk assissment of exposure of the painting unit workers of a bicycle industry to BTEX compounds and to provide control solutions.

In this cross-sectional study, 48 personal exposure samples of workers during of two seasons of winter and spring were collected using NIOSH 1501 method from six sections of painting unit in a bicycle industry and then analyzed by GC-FID and their risk was estimated by EPA method.

The cancer risk of benzene and ethylbenzene in all sections was exceeded from the EPA acceptable criteria. The paint preparation cabin had the highest cancer risk, with  8.2 per 1,000 cases for benzene and with 1.2 per 1,000 workers for ethyl benzene. Non cancer risk of benzene in all sections, toluene in the primer paint cabin, polishing and finishing paint cabin and xylene in the paint preparation cabin and cascade painting exceeded the EPA criteria.

Due to the high level of cancer risk of benzene and ethylbenzene in all sections as well as the high non-cancer risk of BTEX compounds in some sections and in general due to the simultaneous presence of all vapors of BTEX, all sections of Paint unit need to improve the work environment such as engineering controls and modify work procedures.

More than 2 million people are exposed to wood dusts every day around the world. Exposure to wood dust increases the prevalence of respiratory diseases and cancer incidence. Therefore, this study was carried out to evaluate the risk assessment of workers exposure to inhalable wood dust in the carpentries in Sari City.

This cross-sectional study conducted in 27 carpentries in Sari City in septumber, October and November ,2017. 43 workers were selected randomly. Inhalable wood dust were measured in the basis of the standard method number 0500 recommended by NIOSH using a calibrated personal sampling pump and an IOM sampler. The risk of exposure to wood dust then was measured using a recommended method by Singapore institute of occupational safety and health.

The average concentration of the inhalable wood dust in total carpentries was 15.30( mg)/m^3 and also in carpentries , MDF cutting, MDF/Carpentry, wood cutting, furniture making and wood carving workshops were 18.58±11.94, 19.49±17.3,8.32±7.5,10.48±6.05,3.44±3.98,4.77±0 mg/m^3 respectively. There was a significant correlation between the concentration of inhalable wood dust and the ambient temperature and the general ventilation. The risk of Exposure to inhalable wood dust were evaluated in the medium levels for all workshops.

The workers’ personal exposure to inhalable wood dust in carpentries in sari city was higher than Occupational Exposure Limit recommended by national and international recommended levels. The higher workers’ exposure to inhalable wood dust was found in lower ambient temperature and in the absence of general ventilation.

There are many chemicals in Portland cement including crystalline Silica. Workers’ exposure to cement airborne particles containing Free Crystal Silica may cause some serious diseases. This study was carried out to evaluate Free Crystal Silica particle concentration in the workers’ breathing zone in a cement factory in the Khorasan Razavi province.

The concentration of free Crystal Silica of respirable cement particles was evaluated on 42 sample of workers in different sections of a cement factory in the Khorasan Razavi province in 2018. Sampling of respirable particles was conducted based on standard method of MDHS101/2 recommended by NIOSH, using a personal sampling pump, a cyclone and a filter. Filters were weighed using an accurate microbalance with one microgram precision. Filter was analyzed by XRD method for determination of free crystalline silica.

The mean workers’ exposure to cement respirable particles was 3.75±4.09 mg/m3 and the average concentration of free silica in cement respirable particles was 0.12±0.3 mg/m3 in all studied sections. On average, 69 percent of workers were exposed to free silica higher than OEL. Maximum average of exposure to free silica (0.54 mg/m3) was observed in stone crushing section and the minimum average exposure was observed in Raw mill section (0.03 mg/m3).

Workers exposure to respirable cement particles and free crystalline silica in respirable particles were higher than national and international exposure limits. There is a relationship between temperature and respirable particle concentration. Regarding high exposure of workers to free crystalline silica respirable particle concentration.

Wood dust have been approved as a harmful and carcinogenic agent for humans. This study aimed to evaluate risk assessment of Workers' exposure to inhalable wood dust among 100 workers in 25 furniture manufacturing workshops in one of the northern cities in Iran.

NIOSH0501 method was used to assess the occupational exposure to Inhalable wood dust and Semi-quantitative risk assessment method recommended by Singapore Department of Occupational Health was used to assess risk level of occupational exposure. Airborne particles were collected from the workers' breathing zone using calibrated personal sampler pump and a PVC filter with a 25 mm diameter, 5 µm pore size embedded inside an IOM Sampler.

The mean occupational exposure to inhalable wood dust among all exposed workers was found to be 22.3 ± 6.9 (Mean ± SD) mg.m-3. The risk level of workers' exposure to inhalable wood dust was also documented to be in medium level in all workshops. In addition, the researchers found that among environmental variables, the door area of workshops was the most effective predictor variable to predict variations of workers' exposure to inhalable wood dust (ADJ.R2=0.113, R2=0.122, p<0.001).

Exposure to inhalable wood dust was several times higher than the OEL of Iran and TLV recommended by ACGIH. Since the risk level of workers' exposure to inhalable wood dust was in medium level, their health could be threatened by prolonged exposure. Therefore, technical-engineering and managerial controls seemed to be necessary.

One of the major health issues in developed countries is the workplace air pollution. Cement factories are one of the industries where many workers worked in them. Workers in this industry are exposure with many harmful factors, such as ergonomics factor, physical factors, and in particular various chemical agents, during their job. The most important factors that threaten the health of workers in the cement industry are dust and respirable particles of cement. Respirable particles of cement contains some elements such as arsenic, calcium, aluminum, cadmium, lead, cobalt, zinc, iron, and chromium. Recent studies concluded that the concentrations of arsenic, chromium, lead, and cadmium within the particles are higher than the other metals. Exposure to heavy metals within cement respirable particles can lead to some adverse health effects among exposed workers. Expanding of industries and emission of respirable particles containing heavy metals in the workplace ambient causes higher exposure for workers within various industries and therefore has become a major problem in these industries, including the cement industry. To arrive the health goal that is protection of the workers, exposure to chemicals and the dangers of exposure to these substances need to be scrutinized. Risk assessment is defined as the process of assessing the risks arising from risks in the workplace by taking control measures and deciding whether or not to accept them. Risk assessment is a basic action for evaluation of danger in the workplace and the first step for risk management. Quantitative health risk assessment for different chemical agents in industries is necessary to decide on control of risk and management measures to reduce risk and determine risk level of these substances. This process combines scientific information about the toxic properties of chemicals as well as the results of chemical measurements in the workplace can provide comprehensive information on the measure of risk and how best to deal with these potential risks. The aim of this study was to assess the risk level of workers occupational exposure to heavy metals (lead, chromium, cadmium) within cement respirable particles for exposed workers in a cement factory.

This cross-sectional study was conducted in one of the cement industries during warm  and cold air condition during 3 months (March 2016 to May 2016). In this study, the concentration of respirable particles within the breathing zone of 70 workers who were working at different production worksites of a cement factory (Packing worksite, Cement mill, Grill and Greater cooler, kiln, blending, Raw material storage and Mine and crushing) was evaluated. The standard method of 0600 recommended by the National Institute of Occupational Safety and Health (NIOSH) was use to evaluate time weighted average (TWA) of workerschr('39') exposure to respirable cement particles. Workerchr('39')s exposure was measured using a personal sampling pump (SKC, model 224-44MTX, UK) with a 2.5 L.min-1 flow rate,   air was passing through an aluminum cyclone (SKC, UK) with a 37 mm 2 micrometer pore size poly vinyl chloride (PVC) filter (SKC, UK) bedding on a plastic cassette. The filters were placed in the desiccator for 24 hours before sampling time. To weigh the filters, a microbalance accurate to 6 decimal places (1 µg sensitivity   Sartorius, Model ME5, Germany) was used. Critical orifice was used to keep the flow constant during sampling period. Workers personal sampling carried out continuously during a complete shift time. A blank filter was used for each batch of samples to eliminate sampling errors. To evaluate workerschr('39') exposure to heavy metals including lead, chromium and cadmium within the cement respirable particles, the standard method of ID121 recommended by the Occupational Safety and Health Administration (OSHA) was applied. Each filter was dissolved separately at 100 ° C in concentrated nitric acid and perchloric acid until its metals were dissolved in the solution phase. Then, the solution obtained with deionized water was diluted to the lowest level of detection (LOD). The US-made FAAS Model VARIAN 240FS atomic absorption device was used for analysis. Firstly the standard curve was obtained using standard solutions with different concentrations of meals. Samples were then transferred to the atomic absorption apparatus to determine the concentration of the metals within solution. By measuring the sample absorption rate and comparing with the calibration curve and using Bier Lambertchr('39')s law, the amount of metal elements in the unknown sample was obtained. Semi quantitative risk assessment of heavy metals among exposed workers was carried out using a standard method provided by the Institute of the occupational health and Safety in Singapore. Finally, the risk level for each of the heavy metals (lead, chromium and cadmium) in the respirable cement particles was obtained. The degree of exposure (ER) for all parts of the plant was obtained. Since the mean concentrations of these metal in the air of all sections of the cement plant were below the exposure limit recommended by the Iranian Occupational Health Technical Committee (OEL) and the (TLV) recommended by the ACGIH, the E/OEL ratio was lower than one. The hazard rating (HR) of the chemicals was determined using a standard table. Then, the exposure rating (ER) was calculated and determined using air monitoring results using E that is the weekly exposure in milligram per cubic meter or parts per million, F is the number of exposures per week, D is the average time of each exposure in hours, M is the exposure rate in parts per million or milligram per cubic meter, W is the average working hours per week (40 h). Finally, the risk rate (RR) was calculated using the chemical hazard risk (HR) and exposure rate (ER) values.

This study showed that the mean concentrations of cadmium, lead and chromium elements were measured as 2.41, 10.39, and 1.36 microgram per cubic meter respectively. The highest average exposure to lead metal in the respirable cement particles was 15.09 ± 4.45 µg / m3 and the lowest mean was 8.48 ± 3.11 µg / m3. The highest mean chromium concentration in cement respirable particles was 2.27 ± 1.15 µg / m3 and the lowest mean was 1.11 ± 0.48 µg / m3. The highest mean concentration of cadmium in the cement respirable particles was 2.78 ± 0.62 µg / m3 and the lowest mean was 2.17±0.37 µg / m3.Most workers in the various cement worksites were exposed to heavy metals less than the OEL suggested by the Iranian Occupational Health Technical Committee and the TLV recommended by the ACGIH. Due to the toxicity of lead metal, the grade 3 risk was considered for this metal. According to the E / OEL ratio, the exposure rate (ER) for all parts of the plant was 1, and since the concentration of this metal in all parts of the cement plant was less than the OEL designed by the Iranian Occupational Health Technical Committee and the TLV recommended by the ACGIH. the risk score for all parts of the plant was 1.73, and finally the risk score for lead in all parts of the plant was low. Due to the toxicity level of chromium metal, the hazard rate (HR) for this metal was considered 5. According to the E / OEL ratio, the exposure rate (ER) for all parts of the plant was obtained 1and since the concentration of this metal in all parts of the cement plant is less than the OEL designed by the Iranian Occupational Health Technical Committee and the TLV recommended by the ACGIH, the risk score was 2.23 in all parts of the plant. And the risk rating for chromium metal was low in all parts of the plant. Due to the toxicity level of cadmium metal the (HR) was considered 4 for this metal. Risk score was obtained in all parts of factory number 2 and as a result the risk rating for cadmium metal in all parts of factory was low. Since all workers in a section are exposed to cement respirable particles and therefore exposed to lead, chromium and cadmium metal elements in these particles are different. The risk of exposure to workers exposed to the highest concentrations of the studied metals in the three sections of kiln, blending, and Cement mill was calculated separately. The results showed that workers exposed to cadmium and lead metals were in the medium risk exposure kiln and blending worksites, respectively and workers exposed to chrome metal working in the cement mill were also at low risk. 

According to the present study, concentrations of chromium, cadmium and lead in the respirable cement particles were lower than the exposure limit set by the Occupational Health Technical Committee of Iran (OEL) and (TLV) recommended by the ACGIH. Exposure to lead, chromium and cadmium elements in cement respirable particles were at a low risk rates for all worksites of the plant However, some workers in the kiln silo and milling materials that exposed to higher particle concentrations containing cadmium and lead had an average risk rate. Therefore, engineering and management control strategies for heavy metal exposure in those sectors are recommended to reduce the risk and prevent injury to these workers.

One of the harmful pollutants in the indoor environments is particulate matters. Particles smaller than 2.5 micrometer in diameter that are suspend in the industrial environments air are the most deleterious dusts which can cause lung disease and cancer. In present study PM2.5 concentration in the fast-food shops air and its cancer risk for shop workers were assessed.   In this descriptive-analytical study, all of Sari city 132 fast foods were included. Air sampling was conducted by calibrated real-time GRIMM-monitor device. Data were analyzed by using of SPSS16 and Prism6 software with T-test, Pearson correlation and descriptive statistics. Finally PM2.5 cancer risk in workers was calculated by EPA method equation. The PM2.5 concentration in shops indoor air (308.5µg/m3) significantly was higher than its concentration in outdoor air (121.98µg/m3) (p<0.05). Highest correlation was observed between indoor PM2.5 concentration with smoking (0.366) and local ventilation (-0.384) (p<0.01). The concentration PM2.5 in the indoor and the outdoor of shops was 273.55 and 86.98µg/m3 higher than acceptable level respectively. Cancer risk was 5.6 per 100 thousands and 1.97 per 10 thousands in the rest and cooking time respectively. The most affective source in the elevation of PM2.5 level in shops indoor air is the cook-emitted particles. PM2.5 concentration in shops indoor and outdoor air was much higher than EPA admissible level and cancer risk for workers was unacceptable that it has required to basic solutions for air pollution control at source.

Considerable increase on the use of electronic devices increased the rate of public occupational exposure to extremely low frequency electromagnetic fields. Assessment of exposure to these fields is highly important due to potential health hazards. This study aimed at investigating the magnetic flux emission from extremely low frequency electromagnetic fields around power lines of high voltage in Neka (north of Iran) and factors affecting the magnetic flux density. In this cross-sectional study, 50 sites around high voltage transmission lines were selected and the magnetic flux density was measured at four different distances from the lines. Humidity and temperature were measured in order to assess their impact on magnetic flux density. The extremely low-frequency magnetic field was measured using an electromagnetic field tester (model TES 1394). Statistical analysis was performed in SPSS V17 applying descriptive statistics and one-way ANOVA. The highest average magnetic flux density was at the 400 kV power transmission line (2.11 ± 1.36 µT). The average magnetic flux density was higher in the afternoon (2.55 µT) compared with that in the morning. The average values for magnetic flux density under the pylon and between two pylons were 1.18 ± 0.75 and 2.55 ± 1.42 µT, respectively. Magnetic flux density decreased by increasing distance from the wire and the environment moisture. The average magnetic flux density was lower than the standards set by the international commission on non-ionizing radiation protection and American Conference of Governmental Industrial Hygienists. Hence, the health effects would be negligible.

Recent studies indicate that the released caused by traffic jams to increase mortality and hospitalization of patients as a result of cardiovascular disease This study tries to investigate the density of PM2.5 dust particles to which taxi drivers are exposed in Bojnord. In this study, the density of PM2.5 dust particles was measured for 677 taxi drivers in 12 main routes of Bojnord in 10 months using a sampling and direct decomposing instrument namely, Micro Dust Pro, to getter with a calibrated personal pump with debit 3.5 lit/min. The results of this study showed that the mean of exposure of drivers with PM2.5, is 108.08 ± 229.64 μgm-3. The minimum exposure for all drivers is 62.37± 79.95 μgm-3 and the highest exposure is 151.06± 96.396 μgm-3.Environmental factors also affected the driver exposure level, with the highest exposure at wind speeds (12ms-1, 134 ± 311.9 μgm-3), wind direction 90-180 (144.8 ± 205 μgm-3) In relative humidity, 81-100% (119 ± 250.9 μgm-3), in cloudy weather (151.7 ± 297.1 μgm-3), and kind of route (on the Shahid street to the airport) (151 ± 370 μgm-3). The results of this study showed that the mean of exposure of drivers with PM2.5, is 108.08 ± 229.64 μgm-3. The minimum exposure for all drivers is 62.37± 79.95 μgm-3 and the highest exposure is 151.06± 96.396 μgm-3.Environmental factors also affected the driver exposure level, with the highest exposure at wind speeds (12ms-1, 134 ± 311.9 μgm-3), wind direction 90-180 (144.8 ± 205 μgm-3) In relative humidity, 81-100% (119 ± 250.9 μgm-3), in cloudy weather (151.7 ± 297.1 μgm-3), and kind of route (on the Shahid street to the airport) (151 ± 370 μgm-3). Keywords: Respirable Particles, PM2.5, Individual Exposure, Taxi Driver

Exposure to respirable cement dust cause some adverse health effects on exposed workers. The aim of this study was to assess the risk of occupational exposure to respirable cement dust for a cement factory's workers and recommend controlling methods to reduce the risk of exposure.
The 0600 standard method of NIOSH was applied to evaluate worker's exposure to cement respirable particles using a personal sampling pump, a cyclone and a filter. For risk assessment of cement respirable particles, a standard method which provided by the Institute of the occupational health and Safety in Singapore was used. Finally, the risk level of exposure to respirable cement particles was assessed.
The results of this study showed that most workers employed in various worksites of the cement production were exposed to dust higher than the OEL recommended by the Technical Committee of occupational health in Iran, and the TLV recommended by ACGIH. Exposure risk assessment in different parts of cement factory showed a moderate risk level for all worksites.
Employees who were working in different worksites of the plant were exposed to risk of cement respirable particles. Thus, the control methods of exposure to particles are suggested.

Background & objeftive: Electromagnetic field comprises electric and magnetic fields which is produced by electricity current. Long term exposures to electromagnetic fields have some adverse health effects on exposed workers. Applications of equipment which create electromagnetic field are increasingly high. Therefore, the current study was carried out to evaluate electromagnetic fields in one of the oil product distribution company in Mazandaran province.
In this cross-sectional study a real time EMF measurement device was used to evaluate electromagnetic field in the vicinity of computers’ monitors, cases, servers, copying machines, and also in electricity posts. Measurement was carried out in 28 sites and the results were compared with national and international standards.
The average of electric field for all stations was 44.4 v/m and the maximum and minimum rates of electric field were 208 and 0.5 v/m related to copying machine and the electricity generator respectively. The mean magnetic field density was 61.7×10-6 mT for all studied sites. The highest magnetic field intensity (5.0×10-4 mT) was found in high voltage fuse box and the lowest (0.2×10-6 mT) was related to electricity control room.
The measured electric and magnetic intensity fields were lower than national and international standards. As the intensity of evaluated electric and magnetic fields were lower than national and international recommended levels, the workers would exposed to safe level of electromagnetic field.

Background and Sick building syndrome (SBS) consists of a group symptoms, including fatigue, headache, nausea, nose irritation, dry skin and redness in which people in a building suffer from the symptoms. The purpose of this study was to assess the symptoms of SBS and its associated factors among staff at a hospital in Kashan, Iran.
The present study was conducted among all staff who volunteered to participate in the research. Totally, 41 subjects were surveyed for SBS symptoms. A MM040EA questionnaire was used to determine SBS among staff and indoor air quality. Chi-square and Fisher’s exact tests in SPSS Software version 16 were applied to analyze the collected data.
In general, the most prevalence symptoms of SBS were headache (85.4%), heaviness in the head (65.9%), low concentration, and dry skin (63.4%). The correlation was found to be not significant between SBS and age (P=0.46), gender (P=0.18), job (P=0.68), and working history (P=0.16). Also, the prevalence of SBS was significantly correlated with noise, low light, and unpleasant odor (P Accordingly, the high prevalence of SBS among staff and its relationship with factors such as unpleasant odor, noise, low light and the effect of the syndrome on the efficiency and the quality of working life, the improvement of lighting distribution and the reduction of noise were proposed for the reduction of SBS.

The hospital environment requires special attention to provide healthful indoor air quality for protecting patients and healthcare workers against the occupational diseases. The aim of this study was to determine the concentrations of respirable particles indoor and ambient air of two hospitals in Kashan.
This cross-sectional study was conducted during 3 months (Marth 2014 to May 2015). Indoor and outdoor PM10 and PM2.5 concentrations were measured four times a week in the operating room, pediatric and ICU2 (Intensive Care Unit) wards using a real time dust monitor at two hospitals. A total number of 480 samples (80 samples indoors and 40 outdoors) from wards were collected.
The highest mean PM2.5 and PM10 for indoors were determined 57.61± 68.57 µg m-3 and 212.36±295.49 µg m-3, respectively. The results showed a significant relationship between PM2.5 and PM10 in the indoor and ambient air of two hospitals (P The respirable particle concentrations in the indoor and ambient air in both hospitals were higher than the 24-hours WHO and US-EPA standards. Thence, utilizing sufficient and efficient air conditioning systems in hospitals can be useful in improving indoor air quality and reducing the respirable particle concentrations.

Occupational stress and employee's health status can affect their productiveness and quality of services. Therefore, it is necessary to evaluate the effective factors in this regard. This study was conducted in order to evaluate the relation between psychological health and occupational stress among the midwives employed at the governmental and private hospitals of Neyshabur, Iran.
In this cross-sectional (descriptive and analytical) study, all of the employed midwives in the governmental and private hospitals of Neyshabur (78 people) were enrolled in the study in 2015. Data was gathered through the standard Goldberg General Health Questionnaire and the Altmaier's Occupational Stress Questionnaire was used. Data analysis was done with SPSS 20.
This research showed that only 14% of the midwives were psychologically healthy, and 86% had some degrees of psychological disorders. Also 54%of them were averagely stressed and 46% suffered from severe stress. The results of this research showed an opposite and significant association between psychological health and occupational stress in midwives (p=0.049).
This study showed that most midwives working in these hospitals suffered from psychological disorders. Probably occupational stress was involved in deteriorating their psychological health.

Carbon Monoxide (CO) poisoning is one of the most common causes of death in Iran. The present study investigated the indoor and outdoor CO concentrations at hospitals under the supervision of Mazandaran University of Medical Sciences in Sari, Iran.Indoor and outdoor measured CO were conducted over a period of one month during the 2012 winter season in 4 hospital kitchens using a direct measurement device specialized for CO. The average concentrations of CO gas through gas measuring stations were considered at three stations both in and out of the kitchens.The highest and the lowest average concentrations of outdoor CO in Fatemeh Zahra Hospital (about 2 ppm) and Zare Hospital (about 0.33 ppm) were measured respectively. Besides, the highest and the lowest average concentrations of indoor CO were detected in Imam Hospital (as 9.66 ppm) and BuAli Hospital (as7.66 ppm). The highest ratios of I/O (approximately 10 ppm) have been conducted between 8:00 and 9:00a.m. The lowest median concentrations of CO (approximately 8 ppm) between 11:00 and 12:00 a.m. have been measured. Concentrations of CO in all hospitals in this study were significant.This fact shows poorly ventilation of kitchen due to lack of ventilation design engineering.

Background and Inhalation of hardwood dust may produce a range of adverse health effects in the upper and lower respiratory system, including asthma, along with Sino-nasal cancer and nasopharyngeal cancer. This study was carried out to evaluate personal exposure to wood dust among workers in chipboard and furniture production saloons in Neka Choob factory, Iran. Gravimetric method No. 0500 recommended by National Institute for Occupational Safety and Health was used to determine the wood dust concentrations in the workers’ breathing zone. The sampling air was drawn through a polyvinyl chloride filter within the breathing zone, using a calibrated personal sampling pump. The mean workers’ personal exposure to wood dust in furniture production saloon (2.87 ± 1.95 mgm−3) was higher than mean exposure of workers whom were working in chipboard saloon (0.93 ± 0.35 mgm−3). The mean workers’ exposure to wood dust for both saloons was 1.70 ± 1.53 mgm−3. The mean workers’ personal exposure to wood dust in Neka Choob factory was higher than Occupational Exposure Limit (OEL) recommended by national (Iranian Committee for Review and Collection of OEL) and European Union Scientific Committee on OEL committees. All workers in furniture production saloon and three workers in chipboard saloon have a mean exposure higher than OEL.

Background and Because of the high traffic flow in the city center in Sari, a walk through survey indicated that the PM2.5 concentrations are likely to be higher than the standards. This study was carried out to determine the level of PM2.5 at the street's curbsides in the city center in Sari. In this cross-sectional study the PM2.5 concentrations were measured in 185 monitoring stations at the curbsides of four main streets in the Sari city centre. 5550 10-s samples were collected using a real time particle monitor. A questionnaire was used to record air pollution related information and data were analyzed by descriptive statistic and ANOVA tests. Mean of PM2.5 concentration was 83μgm-3 and it was two times more than the national one and EPA recommended 24- hour standard (35μgm-3). This study showed that mean of PM2.5 concentration at the street during traffic rush hours in the morning and evening were higher than those measured in the afternoon. Because of the high concentration of PM2.5 in the Sari’s city centre that resulted in this study, the 24- hour PM2.5 concentrations are likely to be higher than standards in some days in the city centre in Sari. Therefore, monitoring and control of air pollution are recommended in this city.

Background and 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. 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. 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. Resuspension of indoor particles and replacement of indoor and outdoor air are amongst the most effective determinants for indoor particle concentrations.

This study was carried out to evaluate tobacco dust concentration and also designing a suitable ventilation system for reduction of tobacco dust concentration in a tobacco processing factory in the north of Iran.Gravimetric method was used to determine the tobacco dust concentrations in the emission sources an also indoor workplace. A local exhaust ventilation system was designed according to the velocity pressure method recommended by ACGIH. Mean tobacco dust concentrations (ranged from 23.56 to 432.59 µgm-3) were higher than TLV-TWA in the proximity of all indoor emission sources where some individuals were working. However, mean indoor and outdoor tobacco dust concentrations (7.71and 0.04 µgm-3 respectively) were lower than TLV-TWA. Totally 5 separated ventilation systems and 5 centrifugal fans were designed and selcted to pull the air through 46 different hoods. Some downward slot hoods similar to VS-708 type were designed for the work-tables in tipping unit and some upward slot hoods that are similar to VS-903 type recommended by ACGIH''s industrial ventilation committee were also selected for tipping manipulation unit. Some enclosing hoods were designed for feeders. Duct velocity of 1060 mmin-1 has been selected for all systems. Total air flow rates ranged from 240-369 m3min-1. A very high efficient bag house containing several bag filters was used to collect dust. In conclusion, because of a high concentartion of tobacco dust in the proximity of sources and risk of workers exposure to tobacco dust, a suitable local exhaust ventilation system was designed to reduce particulate air pollution concentrations in a tobacco processing factory.

Background and Ëxposure to respirable particles (PM2.5) causes adverse health effects, such as: respiratory and cardiovascular diseases and eventually death. Çonsidering congested traffic flow in the city center of Sari, it could be expected that exposure of citizens to particulate air pollution would be high. The aim of this study is to survey concentrations of PM2.5 inside and outside of shops and to determine other factors effective upon concentrations of PM2.5 inside of shops in city center of Sari. This study was carried out in and outside of 185 non-source shops that were located on 4 main streets in the central part of the city of Sari. Â calibrated real time dust monitor (MicroDust Pro) was used for sampling. Sixty 10-second samples were collected from in and outside of each shop and relevant information was recorded in a questionnaire. Mean outside concentrations of PM2.5 (83.6 µgm-3) were higher than inside PM2.5 levels (82.2 µgm-3). Çoncentrations of PM2.5 inside the shops had a significant correlation with the concentration of these particles outside. The mean of concentration of PM2.5 was the highest during the high traffic flows in the morning and evening. Â weak but significant correlation was found between inside concentrations of PM2.5 and other air-pollution-related variablesÇonclusion: Results showed that the concentration of PM2.5 particles outside the shops is the main cause of their accumulation inside. Çoncentrations of respirable particles (PM2.5) in and outside of shops in the city center of Sari were higher than the recommended 24-hour standards

Since individuals spend the majority of their times indoors, fine particles generated in indoor combustion processes and by resuspension are important for health effects assessment. The nature and magnitude of indoor particle exposures can change rapidly because of the rapid changes in activities and sources. Indoor PM2.5 concentrations were measured in indoor office, café, and home where people spend majority of their time in there. A real time monitor was used to provide a high degree of resolution for investigating temporal patterns in particle concentrations. The average PM2.5 concentration obtained from the direct reading compared with the mean PM2.5 concentrations that are obtained by gravimetric measurements during the same continuous sampling. Mean PM2.5 concentrations in the big office were more than twice as high as those measured in the small quiet office (19.8 and 7.3 respectively). In the home, cooking increased PM2.5 concentration. The highest particle concentrations in home (average 28 µg m-3) were related to a period around midnight when there were a larger number of occupants inside the living room. Mean PM2.5 concentrations measured in the smoking area of the café were much higher than those measured in the non-smoking area (50.0 and 17.6 µg m-3 respectively). Outdoor air pollution can affect the indoor particulate concentration when the indoor source not exists. Smoking, cooking, and resuspension of indoor particulate matter are the most important sources for indoor particle concentrations.=

Background and Heat is a common type of energy that is produced during industrial processes in many work places. Workers who are working in hot areas may be exposed to heat stress. The aim of this study is to evaluate the effect of a designed cool spot on reduction of Mean Radiation Temperature (MRT) and Wet Bulb Glob Temperature index (WBGT) on a group of furnace workers. First، MRT and WBGT indices were measured to evaluate heat stress in a furnace workplace. Then a suitable cool spot was designed and constructed using a double layer insulator. Finally MRT and WBGT were measured and then compared between inside and outside cool spot simultaneously to ascertain the effect of cool spot on control of heat stress. We found that mean MRT (43. 8 ◦c) and mean WBGT index (29. 5 ◦c) were both higher than threshold limit value (28 ◦c) recommended by ÂÇGÏH in workers'' position. There was a significant difference between inside and outside cool spot in mean WBGT (22. 8 vs. 29. 6 ◦c) and mean MRT (28. 6 vs. 43. 8 ◦c). Çonclusion: Furnace workers who are exposed to radiation and convection heat may suffer from heat stress and we found that a cool spot in workplace is a suitable and feasible method to reduce heat stress.