Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

Journal Issue Information

Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
Author(s): 

Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    72-82
Measures: 
  • Citations: 

    2
  • Views: 

    53
  • Downloads: 

    0
Keywords: 
Abstract: 

Yearly Impact: مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    1-12
Measures: 
  • Citations: 

    0
  • Views: 

    510
  • Downloads: 

    0
Abstract: 

Background and aims: Clean air is one of the basic needs for health and well-being. However, along with economic growth and development, transportation, urbanization and energy consumption have also risen and provide many concerns such as air pollution, which require urgent and wide attention. Air pollution in the worldwide is considered as a risk factor for human health and one of the main challenges of modern countries. In this regard, the organizations responsible in different countries, determine the rules of the threshold limit values of pollutants such as: carbon monoxide, nitrogen oxides, sulfur compounds, heavy metals, volatile organic compounds and propose solutions for their control. Air pollution sources are mainly composed of: suspended particles, volatile organic compounds, carbon monoxide, ammonia, sulfur oxides, carbon dioxide. Meanwhile, volatile organic compounds are one of the most important pollutants in communities due to their significant and irreparable effects on human health and high production. These compounds have been rejected due to the destruction of the stratospheric ozone, photochemical oxidant precursors, acid rain, climate change and global warming, effects on the nervous system, cancer, and so on. In order to eliminate and control these emissions, several methods have been identified such as catalytic and thermal oxidation, condensation, biological, membrane separation, absorption and adsorption. The methods mentioned each for different reasons and functional characteristics have their strengths and weaknesses in utilizing air purification technologies. However, adsorption is one of the most effective control methods and activated carbon as a porous and non-polar adsorbent is one of the most widely used adsorbents due to its hydrophobicity, high surface area, high adsorption capacity and relatively cheap price in this field. In spite of the proper efficiency of activated carbon in the adsorption of pollutants, especially for volatile organic compounds, attempts to improve the adsorption capacity of activated carbon by various methods are being carried out with researchers. Conventional modification methods for increasing the adsorption capacity of activated carbon, includes: chemical methods (acid treatment, base treatment), modification by impregnation, physical methods (thermal methods, oxidation), biological methods, ozone, plasma (dielectric barrier discharge plasma), microwave, and so on. In recent years, the use of plasma has increased significantly in order to modification of surface of various types of materials and compared with other conventional technologies in the field of modification of surfaces, as a promising method, in a shorter and easier time. In addition, there are no secondary pollutants in it. Plasma is ionized gas that all or a significant portion of its atoms have lost one or more electrons and have become positive ions. Types of non-thermal plasma includes: corona discharge, DBD (dielectric barrier discharge), glow discharge, microwave discharge, gilding arc discharge etc. In fact, this method is very efficient and easy to modification of surfaces, and by making physical and chemical changes in the surface structure of materials, the surfaces are modified. Physical changes are mainly caused by UV radiation and other radiation emitted from the discharge to surface, production of active particles such as ions, free radicals and ozone gas and usually affect the porous structure of the adsorbent in order to increase the adsorption capacity. Proper physicochemical background and widespread use of activated carbon in the removal of air pollutants (especially volatile organic compounds) have led to special attention being paid to altering the structural and chemical properties of these adsorbents using other existing techniques and emerging techniques of air pollution control knowledge by various scientists and researchers. Therefore, the purpose of this study was to make significant changes in the structural properties of the adsorbent by using the plasma method as the newest techniques of air pollution control knowledge in order to increase the adsorption capacity and efficiency of adsorbent. Methods: Merck's activated carbon granule with mesh 12 as an adsorbent and Merck's toluene with 99. 9% purity were used as pollutant. This study was conducted in two separate parts. The first part is related to the plasma modification process, which were affected by four variables: temperature (40, 70, 100, 130 ℃ ), flow rate (0. 12, 0. 25, 0. 50, 0. 75 "Lpm"), exposure time with plasma (1, 2, 3, 4 min) and voltage (0. 6, 0. 8, 1, 1. 2 "kV"). Modification setup consists of high voltage power supply (alternating current), cylindrical DBD reactor as 1 mm thickness, anode and cathode respectively of foil cooper and stainless steel, respectively plus two multimeters separately (for simultaneous reading of ampere and voltage). In the second section, the modified activated carbon granule samples were adsorbed with toluene vapors at a concentration of 200 ppm. The measurement of the toluene vapor concentration was also performed by direct reading using a Phocheck based on photo ionization detector. The breakthrough time and adsorption capacity of each activated carbon granule beds were determined and calculated separately. Activated carbon granule beds with the highest breakthrough time and adsorption capacity were investigated with SEM and BET analysis for the specific surface area, porosity diameter and morphology of activated carbon granules as the most important adsorbent properties. Analysis of variance of Minitab software was also used to determine the correlation between variables of the modification process (temperature, flow rate, exposure time with plasma and voltage) with breakthrough time and adsorption capacity. Results: The results show that, the maximum breakthrough time and adsorption capacity of modified activated carbon granules are in 130℃ temperature, 0. 75 Lpm flow rate, 1 min exposure time with plasma and 1 kV voltage. In these conditions of modification, 56% increase in adsorption capacity was observed in comparison with the unmodified activated carbon granule. However, there was no significant effect on the results of BET tests (in order to study of the specific surface area, total pore volume and mean pore diameter) and the reason for the slight changes observed is the effect of the plasma process on the adsorbent surface, which has resulted in the destruction or blockage of some pores. Meanwhile, Fe-SEM images (with a magnification of 30, 5000, and 150, 000) indicate the slight change in the micro and nano scales on the modified activated carbon surfaces in comparison with the unmodified activated carbon surface. In fact, the surfaces of activated carbon granules exposed to dielectric barrier discharge plasma is better in terms of the presence of waste and pollutants on the surface than the unmodified activated carbon. The reason for the decrease in adsorption capacity in some beds can also be due to the high voltage during prolonged exposure which results in degradation of pores and active molecules on the adsorbent surface. However, sometimes increasing the functional groups on the surface of the adsorbent can lead to clogging of pores and a decrease in the specific surface area and ultimately decrease the adsorption capacity. Among the variables of the modification process, except for the temperature, no significant correlation was found between the variables (flow rete, exposure time with plasma, voltage) and the adsorption capacity of the modified activated carbon samples, and only the temperature variable showed a significant level of P-value. Some studies have similar results in this regard. In one study, after survey of the orange acid adsorption in aqueous solution by plasma-modified activated carbon fibers, they reported that the modification process resulted in a decrease in the specific activated carbon level and the increased adsorption capacity of orange acid was attributed to the increase in functional groups. In another study of mercury removal through adsorption on activated carbon modified with plasma, a slight decrease in size and total volume of pores, a slight increase in the mean diameter and specific surface area of meso and macro pores, the increase of the oxygen-containing functional groups, increases in the active sites related to chemical adsorption on the adsorbent surface and finally increase in adsorption capacity were reported. Conclusion: Based on the results obtained and as well the results of other studies, the reason for increasing the adsorption capacity of toluene vapors on the activated carbon granule, despite the reduction of the structural properties of the activated carbon after modification, can be attributed to changes in the chemical properties of the adsorbent surface (functional groups), which requires further studies in this regard to confirm its accuracy. Generally, plasma as a novel and eco-friendly method, by making changes in the chemical and physical properties of activated carbon granule, leads to an increase in the adsorption capacity of toluene vapors. The most important reason for increasing adsorption capacity attributed to chemical changes on the adsorbent surface affected by the modification process.

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    13-21
Measures: 
  • Citations: 

    0
  • Views: 

    322
  • Downloads: 

    0
Abstract: 

Background and aims: Eyesight is considered as one of the most important senses in the human being. In this regard, it is necessary to provide optimal lighting in the living environment and to show objects and enhance differential contrast, as well as preventing visual fatigue and glare. The advancement of technology and the increased need for shift work have made individuals, according to their type and nature of work, exposed to highintensity light. Among such occupations, which are considered as very precise jobs, we can mention clockwork, mapping, electronic work, etc. High levels of natural or artificial lighting in some businesses can be considered as a harmful physical factor. In-vivo studies have shown that exposure to light can affect fertility and the quality of semen and sperm. Hereof, papers mostly focus on the effects of non-visible radiation or on the effect of radiation wavelengths, and less studies have been conducted to investigate the effect of visible light, in particular on the high intensity of lighting, on semen parameters. Since high light level of natural or artificial sources in some workplaces may be considered as a hazardous physical agent, the present study aimed to assess the effect of light level of 1000 lux on sperm parameters in mice. Methods: The study population included 12 healthy male adult mice of the same age (7 weeks) with approximately the same weights (30 ± 2. 5 g). Six were considered as a control group and six were considered as case group. Animals were kept in polycarbonate Plexiglas containers during the test and after testing time kept in special cages. Food and water were freely access available to the animals. The average temperature of the room was 24-28° C, the relative humidity was 60-40%, and the air velocity was 0. 14-0. 16 m/s. Light intensity measured during 8 hours of daily exposure was 1000 lux and at animal room less than 100 lux were measured by a lux meter. The amount of light needed for testing was only provided through a projector equipped with 400-watt metallic halide bulbs with white light. Experiments were conducted under controlled conditions for a period of five consecutive days and eight hours of exposure daily. At the end of the exposure scenario, animals of each group were anesthetized with Ketamine-xylazine injections, the epidermis of the testicles was stretching out and put on in a culture medium for semen analysis. Paraffin molds and 5-micron slices were provided and all tests related to tissue index were performed on the samples. Also, by optical microscope with magnification of 400x, spermatogonium, spermatocyte, spermatid and sperm cells was counted. The internal and external diameter of the sperm tubes was calculated using the Image J software. The mean three-time intra-group replication of the data with a significant level of 0. 05 was reported. Data were analyzed by one-way ANOVA and Tukey's post hoc tests. Results: in assessing the morphology of sperm in case group, the more abnormalities (with hairpin curved sperm) was found than the one of the control. There was a significant difference of the internal diameter of the spermatozoa tubes (case: 97. 11 ± 1. 79 μ m; control: 66. 82 ± 1. 02 μ m) between the case and control groups (P<0. 01), while there was no significant difference between the two groups in case of the external diameter (case: 160. 27 ± 1. 95 μ m; control: 161. 98 ± 1. 33 μ m) (P>0. 05). The percentage of total motile sperms (case: 60. 7 ± 0. 96; control: 72. 4 ± 1. 02), percentage of sperm with normal morphology (case: 45. 50 ± 3. 58; control: 73. 35 ± 1. 6) and the percentage of living sperm (case: 58. 68 ± 1. 44; control: 74. 36 ± 1. 65) were significantly different between the two groups (P<0. 01). No significant difference in the number of sperm in millions (case: 4. 11 ± 1. 11; control: 4. 51 ± 0. 09) was observed between the two groups (P> 0. 05). Microscopic images showed that the internal diameter of the spermatozoa tubes in the case group have been changed in comparison with the control group. Result show tissue degradation, disruption of spermatogenic cell and destruction of the medial part of the spermatozoa tubes in the case group as compared to the control group. The presence of irregularity, entanglement and abnormalities in the case group was clear compared to the control group. Conclusion: The aim of this study was to investigate the effect of exposure to light 1000 lux on sperm parameters in male mice. Previously, a similar study on the effect of high intensity lighting on reproductive ability and quality of semen was not reported. While today, exposure to high-intensity light in precise jobs and shift works is so common. According to the findings of this study, exposures to light 1000 lux reduced motility, percentage of natural morphology and rate of living sperm, which is expected to increase the possibility of different degrees of infertility in male. Also there was an increase in the internal diameter of the spermatozoa tubes due to exposure with 1000 lux, indicating cell differentiation and death in a large number of reproductive and germ cells of different classes. Cellular mechanisms regarding the interaction between visible light and sperm are still debatable. Most researchers believe that the first step in finding the interaction between light-cells is the formation of reactive oxygen species (ROS) by light-sensitive elements in endogenous cell. Although in male reproduction, ROS is known to be harmful to sperm function, it has now been shown that very low concentrations of ROS in signal transmission pathways lead to sperm acrosome responses, which seems essential for fertilization. The results of other studies show that visible light can change the redox state of sperm cells by inducing ROS production. Since one of the most important functions of the regulator cells is to maintain cell redox homeostasis, this change can modulate the intracellular movement of Ca2+. Changes in ROS and Ca2+ both play a vital role in controlling sperm motility and fertilization capacity of mammalian sperm. In addition, a study has shown that visible light increases the amount of ATP (Adenosine triphosphate) in sperm cells. However, more studies are needed to fully investigate the effects different intensities of visible light exposure on the sperm fertilizing ability. Since the precise determination of the cellular redox state depends on the cellular conditions and the parameters of the light used for radiation, the optimal light conditions for each animal's spermatozoa for therapeutic purposes should be determined. Considering that studies focus mainly on lower intensity of visible light, in order to conclude definitively, more comprehensive studies are required on different animal species or on human sperms. Due to the fact that today, in precise and high-precise jobs, exposures of people with high-intensity radiation occur, it is advisable to take appropriate control measures in the workplace in order to prevent the potential adverse effects of exposure to high intensity illumination. In conclusion, according to our findings, exposure to the light level of 1000 lux may reduce total motility, natural morphology percentage and survival rate of sperms, which is expected to increase with the possibility of different degrees of infertility with male factor over time. There was also an increase in the internal diameter of the sperm membranes due to the exposure to 1000 lux, indicating cell differentiation and death in a large number of different germ cells.

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    22-34
Measures: 
  • Citations: 

    0
  • Views: 

    375
  • Downloads: 

    0
Abstract: 

Background and aims: With the developing use of electricity in all aspects of human life, electricity accidents have also increased. Electricity is the most important type of energy used in workplace and has a direct relationship between economic development and its consumption. Every year, more than 5, 000 deaths from electric shock occur in the US construction industry, accounting for about 20% of the deaths from accidents. The incidence of electrical accidents is 25 times greater than the incidence of falls. Therefore, it is essential to take the necessary measures to prevent such incidents. One of the main components of the prevention policy, is the safety performance assessment of the organization's or industries by using appropriate performance indicators with related operations. Safety performance indicators are divided into two main categories: the leading and the lagging indicators. The leading indicators show the organization's actions in predicting and preventing incidents before they occur, while the lagging indicators show the organization's performance after the occurrence of the incidents. In many activities, such as construction phase due to rapid changes in the nature of activities and subsequent changes in the level of operational risk, it is essential that safety performance indicators become more responsive and sensitive to changes in the safety level of operations. The aim of this study is to develop and validate active indicators for assessing the safety performance of electricity in the phase of construction of oil and gas refineries using Bow Tie and Network Bayesian techniques. Methods: This is a descriptive-analytical study carried out in the phase of construction of oil and gas refineries. In the first phase, the construction operations were identified by studying the WBS refinery project. Work Breakdown Structure is a graphical network or graphical structure for showing a product or service production method, including hardware, software, services, and other tasks of the organization or company. At this stage, the main activities of the construction phase were identified using the WBS project. In this study, hazardous construction phases were identified and classified by PHA. Considering that determining the causal network and probability of a failure is one of the important factors of risk assessment and determination of safety performance indicators, in the third stage, the relationship between the causes of the incident and the occurrence of the underlying causeswere researched using expert panel. The Bayesian network is an important tool for determining causal relationships and calculating the probability of accidents. The Bayesian network is a graphical probability model that shows a set of random variables and conditional dependencies between them. After determining the probability of occurrence of the root, intermediate and direct causes of the electric shock, the Bow-tie risk assessment technique used to determine the control measures related to each of the causes. By surveying the relationship between the causes of the electrical incident, the active indicators related to the field of electrical safety were identified and in the last step, validation of the indicators over a 6-month period done by comparing the results of measuring the active indicators and the frequency of incidents recorded through Regression correlation test was performed. Results: In this study, six disciplines including electrical, instrumentation, piping, tanks, communications and buildings, and 18 electrical hazardous activities identified. Based on the results of the WBS review and the preliminary risk analysis of identified activities, the causal network electric shock accounted for the expert’ s opinion. The probability of occurrence of electric shock was 0. 053 calculated using the method of BN. The electric shock caused by a collision with the under-ground cable (A) and the contact of the scaffolding pipe with the power cable (E) the largest share of the potential for electric shock. By using technique Bow tie, control measures including a RCD, earthing system, inspection and supervision, training, permit to work at drilling, scaffolding, work to height and maintenance operations and Ricket Fire, are set to reduce the probability of occurrence of events. 11 active performance indicators include drilling performed with permission to do work, boards with RCD and Earthing, earthing generators, generators with installed safety instructions, generators with fire extinguisher, scaffolds authorized to do work, Number of electrical safety inspection, cranes with electrical insulation cabin, operators trained and earthing Conex. In order to determine the correlation between active indicators and incident frequency indicators, information on five contractor companies collected and measured during six months. Then the linear regression model used to determine the statistical relation. The R-square value of the incident frequency with the active performance indicators of A, B, C, D and E companies is 0. 996, 0. 495, 0. 998, 0. 863 and 0. 797, respectively, with the highest linear regression, respectively C, E, A, B and D companies. The p-value in A, B and D companies is greater than 0. 05 and in C and E companies is less than 0. 05. Therefore, these results indicate that the correlation between incidents frequency as dependent variables and active performance indicators as Independent variables in A, B and D companies are not significant, but the correlation between C and E companies is significant. The R-square value of the incident frequency with the active indicators of the total project was 0. 819 and P-value was less than 0. 05. Therefore, these results indicate that the correlation between incident frequency as an associated variable and active indicators as independent variables in the whole project is significant. Conclusion: This study was performed to determine the safety performance active indicators of electrical of construction phase of oil and gas refineries. In previous studies, such as the Podgorski (2015) and Flahati (2017), the leading performance indicators developed according to ILO-OHS-2001 and OHSAS 18001 management system components. One of the main objectives of the development of safety performance indicators in construction projects is to rank and compare the safety performance of the contractors in the project. Therefore, it is necessary to consider all aspects of the performance management system in order to make a proper judgment of the existing situation. The performance indicators presented in the Podgorski study (2015) emphasize only the components of the safety and health management system. While the model presented in the present study categorizes the indicators according to the definition of Hinze (2013) into two types of active and passive indicator. Given the rapid changes in operating conditions in the construction phase, leading performance indicators should be able to detect rapid changes in the level of safety of activities. Abdelhamid TS et al. (2000) declared the failure to identify unsafe conditions as one of the root causes of construction projects incidents, so active performance indicators should be able to measure the safety of construction operations in short term periods. The strength of this study is to use the Bayesian Network to determine the cause of the incident. The superiority of Bayesian network in assessing the risk and determining the route of the events is that nodes can considered dependent. Therefore, it is easier to determine the relationships between the different levels of the causes of the incident and the estimation of the probability of occurrence of accidents is more accurate. One of the main constraints of previous studies was the lack of validation of leading performance indicators. In this study, were validated the developed indicators. Correlation between accident frequency as dependent variable and active performance indicators as independent variables is high in all five companies, but in firms A, B and D this correlation is not significant. One of constraints of this study is the short duration of measurement of indicators in a sixmonth period, so the results will be more accurate with increasing the measurement time of the indicators. This study indicates that determining the leading indicators in addition to the components of the safety management system should be based on the type of operations and identified workplace hazards. The leading performance indicators of the safety management system components are mostly passive and cannot show the changes in the level of safety of the workplace in a short time. Because construction operations are inherently high-risk and safety-related changes are taking place rapidly, it is therefore necessary to adopt active indicators as complementary passive indicators. Considering the many variables that affect the occurrence of major industrial accidents, determining the causal relationships between these variables is complex. Therefore, using high reliability methods such as Bayesian network increases the reliability of the active performance indicators derived from the network causing accidents.

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    35-45
Measures: 
  • Citations: 

    0
  • Views: 

    490
  • Downloads: 

    0
Abstract: 

Background and aims: Lead is ubiquitous and one of the earliest metals discovered by the human. This metal is widely used in different industries due to its important physico-chemical properties like softness, high malleability, ductility, low melting point and resistance to corrosion. Lead absorbed in body with several routs and when transfer in blood is primarily attached to red blood cells. Human exposure to this toxic metal and its compounds occurs mostly in lead related occupations and also non-occupational exposures can acccure. Lead and lead compounds are not beneficial or necessary for human health, and can be harmful to the human body. The health effects of lead are directly related to the concentration of lead in the affected organe. Lead can affect on various organs in the body and it is one of the causes of problems and health conditions, including effects on central nervous system and cuses anemia, abnormal behavior, depression, nausea, fatigue, Lead colic, high blood pressure, joint and muscle pain and headache. Also researchs show that Lead causes other health problems such as toxicity of the liver and kidneys system. Initial symptoms of lead poisoning are non-specific and some factors such as age, the amount of lead, whether the exposure is over a short-term or a longer period will influence what symptoms or health effects are exhibited. Due to the toxicity of this metal, it is necessary to investigate exposures of this toxic heavy metal in different environments. Lead exposure at mines is a concern therefore to determine the concentration of lead in air and blood samples of miners; air and blood sampling were down with specific methods. Another part of the study was the estimate of miners skin exposure that for this porpuse, DREAM (Dermal exposure assessment method) model was used. Methods: This study is a cross-sectional, descriptive-analytic research that was conducted on workers of a lead and zinc mine in Isfahan province. This research includes workers with at least one year of work experience. The oncentration of lead in the respiratory air of 46 workers was measured and of these, 40 blood samples were taken. In order to sampling and analysis of respiratory air samples, NIOSH7082 method was used that in this method for Lead sampleing the cellulose ester membrane filter was fitted into a holder and the calibrated individual sampling pump with a flow rate of 2 liters per minute was connected to the filter holder. After completion of the sampling, analysis was carried out using an atomic absorption spectrophotometere, flame. Biological monitoring of lead was performed on the basis of NIOSH8003 method after obtaining informed consent from the personnel and a complete explanation of the sampling steps. After collecting blood samples and preparing of them, analysis was performed using atomic absorption device. At the other stage of the research after extracting work information, the DREAM model was designed by the authors in Excel 2016 software. DREAM model, consists of an inventory and an evaluation part so the inventory part comprises a questionnaire with some modules consist of exposure, department(the observer indicates whether exposure to chemical or biological substances is likely to occur), company(general information on the company), job (job titles are defined and information on workers’ hygiene is obtained), agent (physical and chemical properties of substances are collected) and task(information is obtained on frequency and duration of task performance). Key items of the exposure module are assessment of probability and intensity of three dermal exposure routes: emission, deposition and transfer. Emission involves mass transport of substances by direct release from a source onto skin or clothing, deposition on skin or clothing describes mass transport from air, ransfer is defined as the transport of mass from contaminated surfaces onto skin or clothing. In DREAM model, exposure assessment for nine different body parts takes place at the task level to assessing both potential dermal exposure (Skin-PTASKBP) and actual dermal exposure (Skin-ATASK. BP). Potential dermal exposure is defined as exposure on clothing and uncovered skin, whereas actual dermal exposure is about exposure on skin. The potential exposure estimate (Skin-PBP) for a certain body part comprises the sum of dermal exposures due to three different exposure routes: emission (EBP), transfer (TBP) and deposition (DBP). Finally, after collecting data statistical analysis of the data was performed using SPSS 22 software and related statistical tests. Results: In this research the average age of mining workers is 35. 5 years, the average weight is 51. 72 kg and the mean of height is 172. 54 cm. According to the results of this study, mean blood lead in different age groups is not the same so that the level of blood leads in the age group of 22 to 38 years old was lower than the age group of 39 to 53years. The results of this study showed that the average blood lead of workers in mining tunnels was 24. 7μ g/dl ± 3. 36 and the average blood lead concentration of workers outside the tunnel was 23. 57μ g/dl ± 5. 80. The mean air lead of the respiratory region within the tunnels is 0. 0205 ± 0. 015 mg/m3 and the mean air lead of the respiratory air region outside the tunnels is 0. 0201 ± 0. 017 mg /m3. Independent T-test showed that workers were not homogeneous in terms of blood lead variable and there was a significant difference between the mean of blood lead (P <0. 001). Results show that although, with increasing work history, the level of blood lead in individuals has increased, but this increase is not statistically significant (P = 0. 224). Comparison of the results obtained from the control and main samples showed that the mean and standard deviation of blood lead in the main and control samples are 24. 5± 5. 43 and 17. 08± 3. 85 respectively. According to the results of the correlation test, there was no significant correlation between the Lead concentration of the respiratory air region, the concentration of leed in blood samples and the actual skin exposure that comes with the DREAM model with a significant level of p= 0. 806 and p= 0. 193, respectively. The mean of lead concentration in respiratory air was compared with occupational exposure limit in Iran so that the average results of the respiratory air lead were 0. 02 mg / m3, which is less than the limit specified. According to the results of this study, the mean blood lead of workers was 24. 5 μ g/dl which is less than biological exposure indices. DREAM model analysis show that 15. 2% of miners had a low exposure rating with lead, 4. 3% ranked average, 13% high, 37% very high and 30. 4% had very high exposure rating. Conclusion: Regarding the porpuse of this study, after careful observation of the process and the different sections and working areas, the level of Lead in the blood respiratory air were measured and analyzed. According to the results of this research workplaces are the most important factor in increasing and reducing blood lead. It is almost impossible to remove lead completely from the human body; therefore, reduction and prevention of lead exposure are very important. The use of appropriate personal protective equipment, the correct use of them, establishment of appropriate time table between drilling and extraction, the use of rubbing non-petroleum products are recommended in order to exposure control to lead. Occupational hygiene has traditionally focused on inhalation exposures to chemical and biological agents and during the last decade, dermal exposure assessment has received more attention. Different approaches are used to estimate dermal exposure that in this research DREAM model was used. Results show that DREAM model is flexible and can be used for dermal exposure characterization for all kinds of scenario and because of its hierarchical structure; it takes on average 15– 30 min only to assess exposure for one person carrying out one task. According to the present study the DREAM is a simple and inexpensive model which is well suited to investigate exposure to lead in the mine. This model supplies an estimate for exposure levels on the skin and outside clothing layer, and gives insight in the distribution of dermal exposure over the body of exposued workers to pollutants. In addition to the advantages, the model also has some limitations, for example since few studies have been done on skin exposures, the values are presented hypothetically. In order to expand this study and provide more definitive views on the DREAM model, it is recommended that in addition to measuring the concentration of lead in air and blood samples in different working conditions, researchers use skin sampling techniques and compare the results with this model. In this study researchers suggested that skin and clothing sampling methods be used to increase the accuracy of determining the amount of lead exposure to skin. Also, the identification and risk assessment of lead exposure in workplace is recommended to determine maximum and minimum of risk level.

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    46-58
Measures: 
  • Citations: 

    0
  • Views: 

    387
  • Downloads: 

    0
Abstract: 

Background and aims: One of the most environmental workplace factors is microwave radiation. In microwave spectrum, radar frequency with 1-300 GHz range have varied applications such as satellite, communications, military, Network, navigation, air-traffic Control, navigation, marine and weather. Uncontrolled occupational exposure to radar radiation caused to various disease and disorders such as oxidative stress, different kinds of cancers and other thermal and non-thermal adverse health effects. Regard to the importance of identification work related carcinogenic factors in prevention and decreasing cancer related costs and lack of similar studies, this study was conducted to systematically review the research on the risk of cancer in occupational exposure to radar radiation with frequency ranges 1 to 3000 GHz. Methods: The present systematic search was carried out based on PRISMA guidelines and comprehensive search strategy was focused from March 2017 to September 2018 and update on September 2018 in PubMed, ISI Web of Science, Scopus and Google scholar, MAGIRAN and SID databases with English and Persian articles without time limits were searched. Keywords were selected based on PICO principle and collected from MeSH database. Comprehensive search were accomplishment by the following search terms: (worker OR technician OR occupation OR military OR airline OR navy OR police officer OR Weather) AND (occupational exposure OR workplace OR long-term exposure OR exposure OR radar OR microwave OR wireless OR high frequency range OR radiofrequency OR radiation OR electromagnetic) AND (control group, cohort OR prospective OR retrospective OR follow-up OR randomized control trial OR case-control) AND (cancer OR malignant OR melanoma OR metastatic OR non-thermal effect OR biological effect OR health effect OR Adverse Effect OR risk factor OR Sarcoma OR tumor or leukemia OR neoplasm OR Carcinoma OR Hepatoma OR lymphoma OR mortality) as single or complex terms in titles, abstracts and keywords. Then, taking into inclusion and exclusion criteria, the process of reviewing, screening and limiting the repeated and unrelated articles was carried out. In addition, manual references checking were done to retrieve the related articles. Also, any disagreements were resolved by consensus between reviewers. The inclusion criteria for selection studies were in design of case– control, cohort and randomized control trial studies, with control group and referring to the association between occupational exposure to radar radiation and all types of cancer in workers. The exclusion criteria were as follows: 1) studies without control group 2) reviews, case and field studies, 3) studies with inhumane population such as in vitro, in vivo and animal studies. 4) Studies that radar frequencies were out of considered ranges (1-300 GHz). 5) studies with other occupational or non-occupational carcinogenic risk factors (such as solvents, workplace air pollution, environmental air pollution, smoking and etc). After implementation of inclusion and exclusion criteria, data were extracted after preparation of the full text of included articles. Results: A total of 533 studies was found. After removal of duplicated references, 272 studies were included for the title, keywords and abstract screening. Then, 219 studies were excluded since they did not meet inclusion criteria. Hence, 53 studies were selected for the eligibility assessment. At the end of selection process and after the quality assessment, 7 studies remained in the systematic review that including 3 case-control studies and 4 cohort studies with no randomized control trial study. A manual search of the reference lists added no more articles in this review. All included studies were from English language and external databases in various countries including USA, Germany, and France. In this systematic review, a study of clinical trials and Persian studies were not found. Finally, based on inclusion and exclusion criteria, 7 articles (4 cohorts and 3 case-controls) were included, which were conducted during the 1950 to 2005 with 51898 sample size and range of ages 15– 69 years that published from 1993 to 2016. Included studies examined relationship between occupational exposure to radar radiation and cancer strength among workers. Whole of the studies put determination of cancers and risk estimates in military workers. The great majority of included studies reported risk estimates with 95% confidence interval. Most included studies were conducted on testicular cancer (4 from 7 included studies) and brain cancer (4 from 7 included studies). In included studies, Relative risk were estimated, particularly about testicular, leukemia and brain cancers and mortality ratio in various types of cancers has been reported. The included studies reported no significant increase in mortality ratio about testicular cancer but increasing in relative risk were significant in two studies. There was also a significant increase in the relative risk of brain cancer in workers who occupationally exposed to radar radiation. Increase in mortality ratio due to brain cancer was significantly reported in two included studies. Conclusion: The current systematic review was carried out to investigate the cancer among workers with occupational exposure to radar radiation. It is noticeable that previous related studies focused on both environmental and occupational exposure in worker and public population and it clearly did not determine the relationship between occupational radar exposure and cancer risk in workplace. Whilst, our study just focused on occupational exposure to radar radiation that lead to small number of included studies. The results of this study can be useful to prepare the occupational health policies in related to radar radiation and provide some information to conduct associated meta-analysis in future studies. On the limitations of the included studies, the continuation of experimental studies on humans with control groups, and focusing on the study of cancer-causing radar radiation in occupational exposure to workers is necessary. in this line, World Health Organization propose to conduct further differences studies especially case-control studies. However, it should be mentioned that these results are yielded by a few numbers of available studies with no report in occupational dose and time exposure to radar frequency range. also, considering to some limitation such as few numbers of included studies, lack of data about exposure characterizations (exposure time, dose-response, average of exposure level) and demographic characterizations (average of age, average of experience, radar frequency range) it is better to continue further studies about this topic and future review studies include the congress publications without limitation in language. It is also suggested that other published articles in congresses also be used and the limitation in language of publications in the search process be removed. It is noticeable that, slight researches about occupational cancers in Iran were conducted in yet, such as studies in related to asbestosis, aromatic amines and chromium. Therefore, regarding the fast growing of cancer in developing countries like Iran, determination of occupational cancer risk factors could be useful to provide the cancer prevention and control program. So in this line, designing epidemiologic studies to focus on occupational cancers are very important especially about microwave and radar radiation.

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    59-71
Measures: 
  • Citations: 

    0
  • Views: 

    333
  • Downloads: 

    0
Abstract: 

Background and aims: The structural characteristics of the human body are influenced by factors such as race, age, gender and type of nutrition, and vary in different nations. Several studies have shown that anthropometric data varies in different societies. It is important to note that despite the high accuracy and low cost of direct measurements of anthropometric dimensions and the existence of extensive databases about them in different societies, there are still numerous problems in direct measurements of anthropometric dimensions of individuals, some of which include: the need to train individuals before measuring the dimensions that are time consuming and with their specific problems, interference in the activities of individuals and, consequently, the possibility of lack of proper collaboration in measuring the dimensions, requires the measurement of dimensions by the homosexual person, especially in Islamic countries, due to the cultural and ethical issues of those societies, and the discontent of most people, especially when it comes to repeat the measurements. Therefore, the role of the use of indirect methods, including the use of biometric regression relations, is more important for estimating the anthropometric dimensions of the target community. The advantages and limitations for each of the commonly used anthropometric measurements and the particular conditions of real working environments have led to the need for a fast, convenient, acceptable, and non-interfering procedure for workers to determine the anthropometric dimensions necessary. In this regard, attention to the biometric relationships of physical dimensions can be useful. Because in the case of finding a meaningful relationship between one or more anthropometric dimensions with other physical dimensions, it is possible to provide the anthropometric characteristics with a high degree of certainty by little time and cost and without the need for specialty. Therefore, this study aims to investigate and determine the ratio of some of the anthropometric dimensions of the indicator, which is used in various designs used by ergonomics and industrial designers, in sitting and standing static situations and in two groups of students in the age group of 18 to 26 years old. Methods: Demographic data were first collected through questionnaires. The dimensions of the study included 20 positions in standing position and 18 dimensions in sitting position. Anthropometric measurements were done using caliper, tape measure, balance and checkerboard sheet (Anthropometer). To increase the assurance of measurements, multiple dimensions were selected randomly and measured by two people. The results of this study were analyzed using correlation coefficient test and if there were no significant differences between measurements by different individuals, the study continued until the end. Otherwise, training was needed for the correct examination method to be uniformed and measurements are repeated. 206 people, including 162 women and 44 men, were enrolled in this study. Sample subjects were selected randomly and clustered among male and female students. According to the main goal of the study, people with severe abnormal BMI, people with a history of musculoskeletal disorders or congenital disorders, people with severe diets, pregnant women and athletes were excluded. In order to increase the accuracy of measurements, all measurements were made in standing and sitting conditions, in a non-shoe mode and with a minimum of clothing (underwear). Also, in order to avoid interference with the measurement of some physical dimensions due to lunch, the time of measurements was selected between 8: 00 and 12: 00. The accuracy of the measurements was considered to be 0. 1 cm in all dimensions. The results of the study were analyzed using SPSS 22 software. In this study, the distribution of anthropometric data was performed using dispersion indices and percentiles 5, 50 and 95, as well as mean and standard deviation. Also, to investigate the biometric relationships of different dimensions in relation to the height dimension of individuals in the population, multiple regression models were used. In these models, the biometric relationship of various dimensions of the body based on height dimension, which was easily measured, was examined in static sitting and standing positions. Results: The results of demographic information analysis of the subjects were studied in two groups of gender and in the age range of 18 to 26 years old. Also, the 5th, 50th and 95th percentiles and standard deviations of measured dimensions in standing and sitting subjects and gender were presented, respectively. In general, 12 regression equations were obtained for standing dimensions relative to height in women and 14 regression equations for standing dimensions relative to height in men. The corresponding values for sitting dimensions were 14 and 12 for men and women, respectively. In accordance with the main objective of the study which was finding relationships between the anthropometric dimensions of individuals in static states to estimate and predict other anthropometric dimensions of a person, the findings of this study showed that the mean and standard deviation of most anthropometric data in women and men have a significant difference with each other (P <0. 05), and in general, its values in women were smaller than males. Also, comparison of 5, 50 and 95 percentiles in standing and sitting anthropometric dimensions showed that there was a significant difference between static anthropometric dimensions in standing and sitting position in both gender groups. So that the standing dimensions in men were more than women in all three percentiles. However, in the dimensions of sitting, the amount of this difference is reduced and in some cases, such as head length, depth of chest, and abdominal depth, there is no significant difference in the 5, 50 and 95 percentiles of men and women were seen. The findings of the existing regression relations between the different static standing anthropometric dimensions and the selected index in this study, which was the height of the subjects, also showed that there is not a significant correlation between height and anthropometric dimensions of the width of the hand, the internal and external distance between the two eyes and the width of the wrist in women. In the 95% confidence interval among women, standing grip reach, length of upper limb and elbow height with correlation coefficients of 0. 791, 0. 742 and 0. 737 have shown the highest fit with height dimension and other dimensions have shown moderate and weak correlations with dimensional dimensions. In men, the shoulder height, eye height and length of upper limb showed the highest relationship with height with correlation coefficient of 0. 949, 0. 867 and 0. 840, respectively. The relationships between different dimensions of body and height of people in this study and the appropriate and acceptable correlation coefficients obtained between the many dimensions such as eye height, shoulder height, elbow height, knuckle height, upper limb length, shoulder-grip length, standing grip and buttock knee length, with the height of the individuals, can be indicative of the fact that acceptable estimates of the dimensions can be obtained by measuring only the height of people. From the total of 38 anthropometric dimensions studied in this study (20 standing and 18 sitting positions), 26 regression relations were statistically significant (P <0. 05) at 95% confidence interval for both men and women groups, separately. Although the relationships were statistically significant, they did not include the same dimensions in the two gender groups. For example, in women, sitting height and sitting shoulder height were significant and had a regression relation, but in men, no significant relationship was found between these dimensions. Conclusion: Due to the limitations of anthropometric measurements during design, the use of biometric relationships can be proposed as a practical, rapid, and acceptable alternative of indirect methods. Based on the results of this study as well as other similar studies, it can be seen that stature can be considered as a suitable indicator and predictor dimension in designs that require specific body dimensions such as shoulder height, eye height, standing grip, upper limb length and elbow height. However, given that the study was conducted in a small student population, and it was not possible to select the same number of people from two groups of gender, it is suggested that, in order to increase the accuracy of the work and the reliability of the results, the complementary and targeted studies should be developed and implemented in the following the present study. So, it is expected that the anthropometric predictive tools such as a predictive software can be obtained so that, by measuring the minimum dimensions of each person as inputs, other dimensions required for design would be estimated, reasonably. Also, although examination of a large number of sitting and standing positions in this study compared to other studies has been considered as one of the strengths of the present study, it is recommended that in later studies, in addition to the relationship between dimensions measured and stature, relationships between stature and other anthropometric dimensions, which can easily be measured, is to be considered.

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    72-82
Measures: 
  • Citations: 

    0
  • Views: 

    437
  • Downloads: 

    0
Abstract: 

Background and aims: Noise exposure as a main problem of industrial world is one of the most common risk factors in industries and many employees expose to it in the workplace. Noise exposure causes a wide range of the discomforts, disorders, and occupational diseases and effects including focus loss, systolic blood circulation changes, sleep disturbances, long-term memory loss, Anger, vascular problems, stress, headache, nausea, irritability, and irreversible hearing loss. Hearing loss in industrial environments is made due to the prolonged exposure with the high level sound pressures and considered as the agent of one third of occupational diseases in Europe. One of the most current and important industries with high level sound pressures in Iran is oil and gas industry. Iran has a special status in terms of oil and gas resources in the region and world, so that it is considered as the fourth crude oil producer, fifth crude oil exporter, and third country having oil reserves. This industry provides the material and energy to other industries and can play a substantial role in economics of developing countries. Abadan oil refinery is largest refinery of Iran and one of three largest refineries in the world. This refinery has been located in Khuzestan province of Iran and occupational noise in mostly its units has exposed the employees to adverse health effects. The results of various studies performed on physical harmful agents, particularly noise, in the oil and gas industry and related companies indicate that noise exposure in some their units is higher than acceptable limit in some units. Given the special status of oil industries and the high volume of labor forces in these industrial units, the present study was aimed to evaluate the workplace noise in operational units of reservoirs and petroleum products transportation of Abadan oil refinery and investigate the impact of control measures on the noise exposure. Methods: This cross sectional and analytical study, was carried out in the operational units of tanks and petroleum products transportation including Crude oil pumping stations 1, 2, and 3, pus oil pumping station, MTBE, Control Center, NTA, KTA, mixing and fusion, fuel transportation, spherical reservoirs, and mazut unit. At the first, the basic information including locations of noise sources and operating conditions of equipment in the various units were collected for determining the noise pollution and identifying the noise productive resources. Then, the values of the sound pressure level were measured using sound level meter, model CEL 490, made by Casella company based on ISO 9612 standard. As well as, the sound level meter was calibrated by the calibrator, model CEL-110/1. In addition, the noise characteristics of the productive resources were determined by ISO 3745 standard. Based on ISO 9612 standard, the studied units were divided to equal squares with the dimensions of five and five meters using a regular network measurement pattern and the centers of these squares were specified as the measurement points. Given that the noise variations were lower than five dB, the values of the sound pressure level were measured at least three times in each point and their mean were calculated as the sound pressure level of each point. The least time of noise measurement in each point was fifteen seconds. To identify the main noise productive resources and dangerous areas with high sound pressure level, the measurement results were depicted in the form of a noise plan. The mean values of air temperature and relative humidity during the measurements were 38 degrees of centigrade and 64 percent, respectively. As well as, wind speed was slow. Give the aim of study, network A was selected as sound level measurement weighting scale and mean height of sound level meter from ground surface was nearly 1. 55 ± 0. 175 meters. After identifying the main noise productive sources in the units, control measures including were determined and implemented based on the type of the noise source. The used control solutions included lubrication of moving parts, repairs, improvement of pumps foundations, reduction of exposure time, and, use of personal protective equipment during exposure to the noise. Based on the type of the noise source, one or combination of control solutions were used. And measurements were carried out in controlled areas. Finally, after performing control measures, the remeasurement of sound exposure in similar situations was carried out in units. In final, the noise measurements were repeated again after performing the control measures based on the stated method. Results: In total, 11 units were investigated in this study. The results of environmental noise pollution measurement in the operational units of reservoirs and petroleum products transportation showed that NTA unit with the mean sound pressure level equal to 89. 28 dB and spherical reservoir unit with the mean sound pressure level equal to 75. 33 dB have the highest and lowest values of the noise pollution, respectively. Based on the results, of 523 measured stations in the present study, 115 stations were with a sound pressure level more than 85 dB, 373 stations with a sound pressure level from 65 to 85 dB, and 30 stations with a sound pressure level less than 65 Db. Of the total measured stations, 71. 3 percent are in alert zone, 21. 9 percent in risk zone, and 5. 7 percent in safe area. NTA unit had the most number of the stations higher than 85 dB and KTA unit had the least number of the stations less than 85 dB. Of total stations with the sound pressure level higher than 85 dB, 19 percent was related to control center unit, 4. 54 percent related to KTA unit, 9. 37 percent related to crude oil pumping station 2, 27. 5 percent related to crude oil pumping station 3, and 34 percent related crude oil pumping station 1. The results determined that the control measures decreased the mean sound pressure level of crude oil pumping station 1 by 2. 39 dB, of control center unit by 1. 7 dB, of pus oil pumping station and MTBE units by 0. 89 dB, and of NTA by 0. 08 dB. As well as, the results of the measurements indicated that the sound pressure level of other units did not significantly change. Conclusion: The results showed that the highest and lowest values of the sound pressure level were related to NTA unit and spherical reservoirs unit, respectively. The most inappropriate stations with the high noise pollution were related to NTA unit. This unit have a great importance among studied units because of the number of people exposed to noise and the value of noise pollution. Given the environmental measurement results, units with a mean sound pressure level higher than 85 dB require the corrective actions, particularly technical engineering measures and effective control strategies, for the continuous improvement. Based on the measurement results, 115 stations have the values of the sound pressure level more than 85 dB. If the engineering and administrative control measures are not implemented, the exposure time should be reduced. The results of the present study indicated that the implementation of the low-cost control methods and the repair and maintenance of the equipment and devices can decrease the noise exposure. In addition, these control measures increase the mean allowable time exposure. These results suggest that the appropriate control measures can cause the optimal use of the workers and professionals in different occupations. Refineries are one of the industries that most parts of it produce the noise pollution. As well as, because of the number of employees, exposure to a variety of harmful agents, and difficult environmental conditions, the control measures such as engineering solutions in oil and gas refineries should be given more attention. To reduce the noise exposure in the operational units of reservoirs and petroleum products transportation, the following control solutions are proposed. The maintenance, repairs, and proper lubrication of the machinery and equipment will reduce the unwanted noise production. It should be noted that the machinery maintenance and repairs not only are necessary for the noise control, but also increase the useful life of the machinery. Vibration also is one of the noise productive sources. Vibration can be controlled using the appropriate foundation, rubber layers, and etc. This solution will reduce the sound pressure level generated by the vibration. As well as, the appropriately choice of the machinery or equipment reduces the level of the unwanted noise. The selection of the machinery with the most consistent and with the lower levels of the undesired noise production due to higher technology are considered as key factors in the strategies to minimize the unwanted noise. Prohibiting or restricting the use of the noise productive equipment can significantly diminish the unwanted noise. In addition, given to 12-hour planning of the staff shift work and the mean value of the sound pressure level in the operational units, job rotation can be effective. Finally, the hearing protective equipment as the latest solution of the unwanted noise control can be applied. If this control measures are correctly implemented, those can greatly reduce the noise pollution and ensure the increase of the employees’ health and productivity.

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Issue Info: 
  • Year: 

    2019
  • Volume: 

    16
  • Issue: 

    4
  • Pages: 

    83-95
Measures: 
  • Citations: 

    0
  • Views: 

    368
  • Downloads: 

    0
Abstract: 

Background and aims: Promoting health and responding to the health needs of people and communities is the most important mission of any country's health system. In recent years، the concept of health and its determinants and on the other hand the health needs and demographic structure of societies have undergone many changes. Fair access to High quality health care seems impossible without formulating appropriate strategies and planning and utilizing human resources management principles. In other words, establishing a balance between workforce and the workload of health workers working in different areas, including suburban areas that have different demographic structure and needs compared to the urban population, is one of the health management requirements. To date, numerous studies have been done in Iran and other countries, but it can be said that the studies are mainly focused on specific areas such as treatment and have included one of the urban or rural contexts of research. Considering the variety of forms of health care systems in different countries as well as the type and variety of services and methods of study, the above studies have had a different approach than the present study. Also، timing of service delivery as the most important factor in improving productivity and optimizing the use of all available health resources and facilities، is necessary for rational and realistic human resource estimation as well as standard time setting. This study was designed to compare the timing of primary health care and the workload of staff working in Qom city comprehensive health bases in urban and marginal areas. Methods: This cross-sectional study was conducted in the second half of the year 1396 (Solar-Hijri) through random sampling from two bases located in two marginal bases of the city and two urban texture bases of Qom. Over a 3-month period, 1000 people-care at comprehensive health bases and age groups for infants, children, adolescents, youth, middle aged, elderly, mothers (prenatal, pregnancy and postnatal cares) were timed. The number of bases and sample size required for the study were determined by Systematic Random Sampling and according to the population of each geographical area in Qom. The four sites studied in this study were selected from four different urban areas. The present study was conducted in 4 stages. In the first phase, in order to coordinate the supervisors and health care providers, an 18-hour workshop was held for uniformizing the method of work, the variety of services, the type of care and the content of the training provided to the target group. During this period, 10 health educators were trained. In the second phase, out of 10 trained caregivers, 4 caregivers with the highest agreement rate in terms of service time, work experience, degree and field of study were selected. Each caregiver was referred to one of the health bases studied each day. In the third step, the timing was done by the Stop Watch method. In this process, the timing of services was recorded by a stopwatch in a complete care consisting of new or periodic care and from verbal communication with the caregiver to the end of full care. Also timing of each service and its components was measured by another stopwatch. Other references to follow-up or examination of tests or referral for purely special care were not subject to timing. In addition, in the event of a power failure or the Internet, the timing process was stopped and the time was recorded, and the duration of the power outage or the Internet was calculated separately and the necessary explanations were noted at the end of the checklist. In the fourth step, after recording the service times and their components in the standard timing checklists, data analysis was performed in SPSS software version 22 using descriptive and analytical statistics including mean and standard deviation and independent t-test. Results: In this study, 96. 1% of clients were Iranian and 3. 9% were non-Iranian. Also, 497 people (49. 7%) of all target groups were living in the marginal areas of the city and 503 people (50. 3% of the samples) were living in urban areas of Qom. Out of 92 referrals for healthy reproductive care, 46 subjects were timed in the marginal areas and the same number in the urban context. The mean age of the subjects was 28. 5 and 31. 5 years in urban and suburban areas, respectively. Also out of 88 referrals that were timed for pregnancy care (including 44 subjects in urban tissue and 44 subjects in marginal areas) the mean age of mothers in urban and suburban contexts was 28. 8± 5 and 27± 6 years, respectively. The mean age of women was 28. 8± 5 and 27± 6 years for prenatal care so 25± 5 and 28. 6± 5 years for postpartum care (respectively at the comprehensive health base in urban and marginal areas). in the case of neonatal and child care the mean age was considered in terms of day (for neonatal care) and month (for child care) and it was 18± 11 as well 20± 11 days (for neonatal care) and 19± 15 as well17± 16 month (for child care) in urban and suburban areas. The mean age (in terms of year) for adolescent and youth care in this study was 11± 4 as well 11± 5 (for adolescent care) and 25± 3 as well 23. 5± 4 (for youth care) in urban and marginal texture, respectively. Based on the findings of this study, the mean age of female middle-aged women cares in urban and suburban areas was 42± 8 years. Similarly, the mean age for middle-aged men in both areas was 40± 7years. Finally, the mean age for the elderly cares was 64± 4 in urban context and 66± 6 in marginal context. In all service packages, except for prenatal care, there was no significant difference between the mean age of the subjects in urban and marginal areas (p <0. 05). In this study, the mean of total time for prenatal and postpartum care was 23 ± 6 and 20± 5 minutes. The mean time of postpartum care was 21. 5 ± 4. 5 and 18 ± 3 minutes (in marginal and urban context, respectively) and the difference was not statistically significant (p = 0. 08). But, unlike postnatal care, the timing of prenatal care showed a significant difference in the marginal (27. 4 ± 4min) and urban (18 ± 3min) tissue (p = 0. 001). Also, pregnancy care with a total mean of 35 ± 9. 5 minutes was the most time consuming care and there was a significant difference in the mean time allocated to this care in the urban (28± 7min) and suburb (39± 8min) context (p =0. 005). Mean timing of healthy reproductive care was 7. 7± 3 and 6. 8± 2. 7 minutes in marginal and urban areas respectively (the total time devoted to these cares was 7. 4 ± 2. 8 minutes. According to statistical tests, the difference between the time of healthy reproductive care in the marginal and urban context was not significant (p = 0. 139). While the results obtained from the timing of other cares provided in the Health Reform Plan package, the average overall time for infant and children cares were 24. 7 ± 5 and 22 ± 6, respectively. The mean time of neonatal care was 27± 7 and 22± 4 minutes (respectively at the comprehensive health base in marginal and urban areas) and the observed difference was statistically significant (p =0. 004). Also, there was a significant difference between the timing of child care in the urban and marginal areas (19± 3. 5 and 25± 6 minutes respectively). In the case of middle-age women care the average overall time was 26. 5 ± 4. 5 min and the difference observed in timing of care (33± 6 and 23± 5 in marginal and urban areas) was significant (p =0. 001). In contrast, the results of the study showed no significant difference between the timing of middle-aged men care in urban (26± 6 min) and suburban (34± 8 min) area (p =0. 29) and the total time of care in this case was 31± 9 minutes. The total time of the elderly care was 33± 9 min (37± 8 and 27± 8 in marginal and urban areas), which showed significant difference between urban basin health and urban areas (p =0. 001). In addition, the mean of total time for adolescent and youth cares were, 32. 5 ± 5. 8 and 24 ± 6. 4 min which did not show any significant difference between urban basin health and suburban areas (p = 0. 1). The mean of time taken to care for adolescents and youths was 40± 6 and26± 6 min in suburban texture 38± 8 as well 23± 7 min in urban area. Conclusion: Differences in the timing of health services and work load in suburban and urban texture health contexts can be used in planning the number of appropriate manpower by the type of care, service location, and needs of the target group in order to provide high quality care in accordance with the principles of human resources. In other words, fairer access to primary health care requires more attention from planners and policymakers to demographic differences and the needs of urban and marginal regions. Further studies are recommended to compare the timing of services in different age and sex groups. A comparative study with other developing and developed countries can also highlight the strengths and weaknesses of the program.

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