2024-03-29T15:32:06+03:30
http://johe.umsha.ac.ir/browse.php?mag_id=19&slc_lang=fa&sid=1
19-361
2024-03-29
10.1002
Journal of Occupational Hygiene Engineering
johe
2383-3378
10.61186/johe
2018
5
2
Comparison of Static Wave Ratio and transfer Function Method in Determining the Sound Absorption Coefficient of Materials
mohammad
oliaei
m.oliaei@edu.umsha.ac.ir
Rostam
Golmohammadi
golmohamadi@umsha.ac.ir
Mohsen
Aliabadi
mohsen.aliabadi@umsha.ac.ir
Reza
Shahidi
rezashahidi2006@yahoo.com
Mostafa
Orvati movafagh
AvaSinaco@gmail.com
Introduction: Sound absorption coefficient determination is one of the most important factors among material selection for indoor noise control. The objectives of this study were: 1) comparison sound absorption coefficient of different materials by standing wave ratio and transfer function methods, and 2) developing a regression model in adjusting provided results.
Methods: In this study, 46 acoustic materials were selected and tested. In order to measure the absorption coefficient of materials two instrument called the impedance tube model 9410 made in the Iranian company AvaSina, and the impedance tube BSWA model SW 260 in 125 to 2000 Hz frequency range were utilized.
Results: The results obtained from the regression model shown that frequency of 500 Hz has the highest correlation (R=0.968, R2=0.936), and the lowest correlation coefficient was founded at 125 Hz (R=0.368, R2=0.136). Also, the value 0.829 was obtained for correlation coefficient of NRC.
Conclusions: The results showed that there were good agreement at 250, 500, 1000 and 2000 Hz frequencies between two methods. It can be concluded that the standing wave ratio method is a reliable approach in determining sound absorption coefficient of acoustic materials.
sound absorption coefficient
Acoustic materials
Impedance tube
Static wave ratio
Transfer function
2018
10
01
1
11
http://johe.umsha.ac.ir/article-1-361-en.pdf
10.21859/johe.5.2.1
19-378
2024-03-29
10.1002
Journal of Occupational Hygiene Engineering
johe
2383-3378
10.61186/johe
2018
5
2
Modeling the Effect of Ammonia Leakage from Ammonia Reservoirs Using ALOHA Software and Developing an Emergency Response Program in One of Process Industries
Gholam Abbas
Shirali
gshirali52@gmail.com
Zeinab
Mosavian asl
Z.mosavianasl@gmail.com
Fereshteh
Jahani
jahani.f71@gmail.com
Atefeh
Siahi ahangar
siahi2068@gmail.com
Salahadin
Etemad
Salah.etemad@gmail.com
Introduction: The most important goal of modeling is to acquire knowledge about the real system's behavior. Toxic leakage in process and chemical industries is likely to be one of the main causes of working people and residents around these industries.
Method: In this study, the ammonia liquid release from storage reservoir in one of the southern refineries was investigated and analyzed using of ALOHA software. This research was modeled on three scenarios: 1. modeling the formation of toxic vapor clouds 2. Modeling the flammable environment 3. Modeling the toxic explosive atmosphere.
Results: Based on the results of this modeling, the concentration of ammonia is 1100, 5 km around the reservoir (red range). The area around the reservoir (orange range) is about 160 miles (about 10 km) from the area. In the event of full leakage of ammonia from the reservoir up to 500 m, the ammonia concentration is about 90000, which is about 60% of the minimum flammable concentration of ammonia gas and up to about 1.7 km of the ammonia concentration tank of 15000, which is about 10% of the minimum flammable gas concentration Ammonia. In the event of a supersonic explosion, the explosive wave pressure is approximately 700 meters from the reservoir equivalent to Psi 8, which can cause serious damage to the buildings.
Conclusion: According to the results of modeling, ammonia toxicity is the most important threat to personnel. Therefore, inspections in accordance with the company's proposal on ammonia repositories and emergency response plans will have an effective role in limiting the harmful effects of toxic and dangerous emissions.
modeling
risk assessment
ammonia
petrochemical
ALOHA
2018
10
01
12
19
http://johe.umsha.ac.ir/article-1-378-en.pdf
10.21859/johe.5.2.12
19-430
2024-03-29
10.1002
Journal of Occupational Hygiene Engineering
johe
2383-3378
10.61186/johe
2018
5
2
Assessment and Risk Management in the Laboratories of the School of Public Health, a Medical University Using the ACHiL Technique
Iraj
Mohammadfam
iraj_f@yahoo.com
Farshad
Abdolahi
farhad.ohs@yahoo.com
Safoura
Karimi
karimisafoura92@gmail.com
Introduction: Despite continuous efforts to reduce risk in different systems, accidents are occurring. The safety of laboratories is important because a variety of chemicals and electrical equipment are normally used, high numbers of students, professors, and staff visit it daily, and there are expensive equipment in such places. For this reason, it is necessary to identify, assess and control the hazards in laboratories by appropriate methods.
Method: In this study, the ACHiL method was used. The ACHiL approach is based on a structure in which 28 risks are classified and each of them has its own allowable limits which is categorized in three levels.
Results: The results of this study showed that chemical agents were the most important risk factor in the studied laboratories. Environmental agents were the second most influential factor in occurrence of accidents. Biological agents and physical agents had the least role in the occurrence of accidents in the studied laboratories. Moreover, the level of hazard and their location were determined according to the severity of each one.
Conclusion: The ACHiL structure is a simple yet highly efficient and effective tool for occupational health and safety professionals to get a full and deep view of the hazards present in the lab and manipulated samples. The method can be used for selecting appropriate safety measures.
Safety
Hazard
Risk
Laboratory
ACHiL
2018
10
01
20
27
http://johe.umsha.ac.ir/article-1-430-en.pdf
10.21859/johe.5.2.20
19-427
2024-03-29
10.1002
Journal of Occupational Hygiene Engineering
johe
2383-3378
10.61186/johe
2018
5
2
Assessment of Human Error Probability in Emergency Evacuation Using HEPI Method in Offshore Industry
Hasti
Borgheipour
hasti_bo@yahoo.com
Ghazaleh
Monazami Tehrani
ghazaltehrani27@gmail.com
Davoud
Eskandari
eskandari.hse@gmail.com
Mohammad
Ranjbar Golmohammadi
m.golmohammadi63@gmail.com
Iraj
Mohammadfam
mohammadfam@umsha.ac.ir
Introduction: Offshore emergency operations are one of the most potentially hazardous incidents. Considering the major role of human factors in this operation, human error assessment is necessary in this section. In this research, the human error levels in emergency evacuation have been evaluated by using the HEPI method.
Materials and Methods: This research was conducted on 17 and 18 alpha platforms in South Pars region. In this regard, the ranked aggregation questionnaire for the HEPI index has been completed based on event factors, stress, complexity, climate conditions, training and experience for collecting data.
Results: The results showed that the risk of the process of returning to safe mode, the activity of immunizing the environment, moving the way to the emergency exits, identification of emergency exits and registering in the TSR was unacceptable. By carrying out corrective actions such as training, repairs, use of safety signs, preparation and delivery of emergency response plans and training for personnel, these activities were within acceptable limits.
Conclusion: According to the results of this study, conducting more maneuvers with respect to their feedback can be effective in reducing the risk of reaction in emergency evacuation. A tool such as HEPI can also provide a better understanding of the concept of human error.
Keywords: Human error; Emergency evacuation conditions; Human error probability index
Human error
Emergency evacuation conditions
Human error probability index
2018
10
01
28
38
http://johe.umsha.ac.ir/article-1-427-en.pdf
10.21859/johe.5.2.28
19-417
2024-03-29
10.1002
Journal of Occupational Hygiene Engineering
johe
2383-3378
10.61186/johe
2018
5
2
Photocatalytic Removal of Xylene Vapor from Air Flow by Using Titanium Dioxide Nanoparticles Immobilized on Synthesis Type 5 Zeolite
Hossein Ali
Rangkooy
rangkooy@gmail.com
Atefeh
Siahi ahangar
siahi2068@gmail.com
Fereshteh
Jahani
jahani.f71@gmail.com
Introduction: Xylene is an organic compound that is volatile and widely used in various industries, which is not only for the environment but also for human health even in low-risk concentrations. Today, among the methods for removing pollutants, photocatalytic removal methods Special attention is paid. The present study aimed to determine the efficiency of removal of xylene vapor from airflow using photocatalytic property of titanium dioxide on ZSM-5 zeolite.
Methods: In this experimental study, the characteristics of the catalysts were determined using BET, X-ray diffraction (XRD) and scanning electron microscopy scanning (FESEM). Xylene vapors were produced using a dynamical condenser system and the efficiency of xylene vapor depletion was investigated using UV / ZSM-5 / TiO2.
Results: Images and spectra obtained from XRD, EDS and FESEM tests showed that stabilization was well done. By increasing the concentration from 50 ppm to 150 ppm and increasing the flow rate from 0.3 to 0.5, the removal efficiency decreased and the removal efficiency at concentrations of 50, 100 and 150 was respectively 35.46, 22.70 And 17.37 percent.
Conclusion: The results showed that the use of composite substrates increases the efficiency of photocatalytic removal, and it is suggested that these adsorption and photocatalytic combination systems be used to remove other volatile organic compounds in the gas phase.
Nanoparticles
Photocatalytic Removal
Xylene
TiO2
ZSM-5 Zeolite
2018
10
01
39
45
http://johe.umsha.ac.ir/article-1-417-en.pdf
10.21859/johe.5.2.39
19-414
2024-03-29
10.1002
Journal of Occupational Hygiene Engineering
johe
2383-3378
10.61186/johe
2018
5
2
Investigation of the Relationship between Inhaled Benzene, Toluene, Ethyl benzene, and Xylene Concentrations and the Urine Metabolites Levels in People Working at a Petrochemical Complex
Davoud
Shahmohammadi
dsm.hse@gmail.com
Sara
Karimi Zeverdegani
s_karimi@hlth.mui.ac.ir
Introduction: Petrochemical industries are known as one of the most important sources of organic pollutants. In this study, the relationship between inhaled benzene, toluene, ethylbenzene and xylene (BTEX) concentration with some urine metabolites was investigated in a petrochemical complex
Methods: This cross-sectional study was an analytical type with 60 inhalation air samples and biological samples. Sampling and decomposition of pollutants were carried out in accordance with the methods of 1501 and 2549 NIOSH , then results were compared with the Occupational Exposure Scale (OEL) and the proposed National Occupational Exposure Indicators (BEI). Statistical analysis was performed using SPSS version 17 software.
Results: The mean concentration of TransTransmuconicand was 137μg/g Creatinine and for Hyporic acid, Phenylglyoxalic acid, Methyl-hyporic acid was respectively 0.577, 0.066 and 0.404 g/g Creatinine. The mean concentration of benzene, toluene, ethylbenzene, o, m xylene, p xylene was 3.818, 4.004, 3.357, 0.132, 2.0159 ppm. The results showed that benzene concentrations in 5 inhalable samples and TTMA in 10 urine samples were higher than the proposed limit.
Conclusion: The mean total concentration of inhaled BTEXs and their urine metabolites was lower than the recommended range of the country. The high correlation between measured pollutants in respiratory air and the concentration of administrative metabolites can indicate that chronic exposure to these pollutants leads to an increase in the excretion of urine metabolites and occupational activity has a significant effect on the health of trainees. In the face of volatile organic compounds studied.
Volatile Compounds
BTEX
Biological Monitoring
Air Monitoring
2018
10
01
46
54
http://johe.umsha.ac.ir/article-1-414-en.pdf
10.21859/johe.5.2.46
19-409
2024-03-29
10.1002
Journal of Occupational Hygiene Engineering
johe
2383-3378
10.61186/johe
2018
5
2
Identification and Analysis of Human Errors in the Maintenance Activities of Molecular Sieve Replacement in the Dehydration Unit of Gas Refineries Using Predictive Human Error Analysis Method
Hamid Reza
Pourimani
hamid_poorimani@yahoo.com
Mostafa
Abbasi
mostafa_a401@yahoo.com
Introduction: Incidental Events in the maintenance activities in the Dehydration Unit of Gas Refineries due to human error, indicate the inadequate effectiveness of the techniques available to identify human errors. The purpose of this research is to identify and analyze human error in this repair activity using the PHEA predictive human error analysis technique and provide appropriate control strategies to prevent or reduce the consequences of identified errors.
Methods: In this technique, all activities and tasks performed to achieve the main goal were identified using the HTA technique, and then possible types of human error in each phases of the above process were predicted and identified by using the PHEA method and using a series of guidance words.After determining the consequences of each of the errors, appropriate control methods were also provided.
Results: Out of 11 operations and 111 sub task occupations analyzed in the PHEA worksheets, a total of 337 errors were identified, of which there were 246 action errors, 13 checking errors, 28 retrieval errors, 33 information communication errors and 17 planning errors. The most significant identified errors are Operation omitted, Misalign, Operation incomplete, Operation mistimed, Right operation on wrong object and Operation too little/too much.
Conclusion: According to the results, functional errors are the most common abundance that emphasizes the necessity of using control strategies in the form of adequate and effective training for personnel, preparation and modification of instructions, monitoring of implementation of work and hardware changes.
molecular sieves
gas refinery
human error
PHEA
HTA
2018
10
01
55
64
http://johe.umsha.ac.ir/article-1-409-en.pdf
10.21859/johe.5.2.55
19-433
2024-03-29
10.1002
Journal of Occupational Hygiene Engineering
johe
2383-3378
10.61186/johe
2018
5
2
Reliability and Validity of the Driver Activity Load Index for Assessing Mental Workload among Drivers in Production Companies
Seyed Abolfazl
Zakerian
Szakerian@gmail.com
Ghasem
Zia
GhasemZia@yahoo.com
Gabriel
Nasl Seraji
jnsaraji@sina.tuma.ac.ir
Kamal
Azam
Kazam@tums.ac.ir
Alireza
Mortezapour
amortezapour258@gmail.com
Introduction: Nowadays, the importance of workload has become more apparent in ergonomic studies. Because workload is part of unsafe situation, it can be the cause of the incident. Therefore, its quantification is important in different occupations. This study was conducted to evaluate the validity and reliability of the DALI questionnaire for assessing the mental load of drivers.
Methods: The present study is a cross-sectional and descriptive-analytic study. All bus drivers operating in one of the manufacturing companies (100 people) entered the study. In order to evaluate the validity, academic experts and queue experts (Lay Experts) were used. To assess the reliability of the questionnaire, 10 people were selected and the Cronbach's alpha and intra-cluster correlation test were used to test the reliability. Data was analyzed using SPSS version 18 software.
Results: The mean (SD) age of participants was 50.8 (8.29) years and the mean (SD) of work experience among drivers was 22.18 (6.22) years. To assess the reliability of the questionnaire, Cronbach's alpha coefficient was used to determine the effective factors in the questionnaire higher than 0.7. Also, intra-cluster correlation coefficient of the questionnaire was higher than 0.7 in all factors affecting the interference factor, which was moderate, which is in the optimum level.
Conclusion: Due to the fact that the validity and reliability indices of the questionnaire were all reported to be desirable, the Dali questionnaire (DALI) as a valid and reliable questionnaire in Iran can be used to examine and measure the mental load of drivers.
Mental Workload
Drivers
Validity and Reliability
DALI Questionnaire
2018
10
01
65
71
http://johe.umsha.ac.ir/article-1-433-en.pdf
10.21859/johe.5.2.65