Journal of Health and Safety at Work

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Introduction: Due to the importance of engineering controls for prevention of microwave exposure, this study was conducted to design and constract a novel electromagnetic shielding and also to examine the factors influencing shielding efficacy in X band frequency range.

Material and Method: This study used Resin Epoxy as matrix and nano-Nickel Oxide as filler to prepare the composite plates with three different thicknesses (2,4, and 6 mm) and four different weight percentages (5,7,9 and 11). The fabricated composites characterized using X-ray diffraction and Field Emission Scanning Electron microscopy. Shielding effectiveness, percolation depth, and percolation threshold were measured using Vector Network Analyzers. Thermal Gravimetric Analysis was conducted to study the temperature influence on weight loss for fabricated composites.

Result: A maximum shielding effectiveness value of 84.18% was obtained for the 11%-6mm composite at 8.01 GHz and the 7%-4mm composite exhibits a higher average of shielding effectiveness of 66.72% at X- band frequency range. The 4mm thickness was optimum and critical diameter for composite plates; and percolation depth was obtained greater than thickness of composites. However, increasing the nickel oxide content did not show noticeable effect on the shielding effectiveness. Thermal Gravimetric Analysis showed that the study shields were resistant to temperature up to 150 °C without experiencing weight loss. What is more, the results indicated that Nickel oxide Nano particles had desirable distribution and dispersion in epoxy matrix and percolation threshold was appeared in low content of nickel oxide nanoparticles.

Conclusion: A novel electromagnetic shield using low thickness and few content of nanoparticle with noticeable efficacy was properly designed and constructed in the field of occupational health. In addition, this shield has low cost, easy to manufacture, resistance to wet/corrosion, and low weight. Epoxy/nickel oxide composite can represents a new generation of electromagnetic shielding, which is considered as a promising candidate for occupational protection against microwave exposure. It is recommended that future studies improve the shielding effectiveness by decreasing the percolation depth and investigate the efficacy of the fabricated shield in the workplaces.

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Introduction: Nowadays, demand for protection against radar radiation using electromagnetic shielding is on the rise.  Double-layer or multilayer shielding were devised in order to improve the single layer electromagnetic shielding properties. In this study, we tried to prepare a new double-layers electromagnetic shield and investigate the effect of structural factors such as thickness, similarity in layers and mixing time on the shielding effectiveness for double-layers shields.

Material and Method: This study used the Resin Epoxy EI-403 and Nickel Oxide nanoparticles to prepare single layer shields by casting method (with two different mixing time: 10 and 66 min) in 2, 4 and 6 mm thicknesses and 7 wt% Nickel oxide nanoparticles. Then, in order to prepare double-layers shields, single-layer shields were placed on each other without air space. Scattering parameters were measured by a Vector Network Analyzer (V.N.A) and shielding effectiveness were calculated in X-band radar frequency range.

Result: The highest and the lowest averages of shielding effectiveness in single layer shields were 84.14% and 46.05%, respectively. These values were 66.34% and 41.99 %, in double layers electromagnetic shields. The averages of shielding effectiveness values in the double-layers shields (with 10 min in mixing time) in 6, 8 and 10 mm in thickness were 41.99%, 45.45% and 43.25%, respectively. These values in 66 min in mixing time, increased to 54.30%, 62.07% and 66.34%, respectively.

Conclusion: In this study, the shielding effectiveness in double-layers were less than single layer electromagnetic shields. Although the increase in mixing time improved the shielding effectiveness of both single and double layer shields, it could not increase the shielding effectiveness in double layer shields in comparison with single layer. Also, the increase in mixing time in double-layer shields showed that shielding effectiveness decreased with increasing thickness in these shields. Also, it was seen that using a similar single-layer shield in the structural of a double-layer shield led to an increase in skin depth and multi reflections .It finally reduced the shielding efficiency in double layer. It is suggested that in the future, other studies be conduct to improve the shielding effectiveness in these electromagnetic shields.

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Introduction: The world is currently facing an all-out crisis over the coronavirus disease 2019 (COVID-19). This review study aimed to determine the applications of the assistive intelligent technologies of the Fourth Industrial Revolution (Industry 4.0) in occupational safety and health (OSH) and response to COVID-19.
Material and Methods: The given review was carried out from May to June 2020 and the search strategy was fulfilled in the databases of Google Scholar, PubMed, and Scopus. The keywords were collected from the Medical Subject Headings (MeSH) database and searched individually or in combination. Accordingly, the articles with the term “COVID-19” in their titles or abstracts and some other keywords such as “smart hospital, Industry 4.0, or intelligent technology” were selected and reviewed. Next, the titles, abstracts, and keywords of these studies were examined. To augment the sensitivity of the search, the keywords and the references of the selected articles were also surveyed. Then, the related studies were separated from the irrelevant ones and the duplicates were removed. Finally, the full texts of the selected articles were reviewed.
Results: In this resepct, a total number of 175 studies, published in the databases of Google Scholar, PubMed, and Scopus in 2020 were retrieved. According to the inclusion and exclusion criteria and qualitative screening, 30 articles were included in this review. The assistive intelligent technologies such as artificial intelligence (AI), the internet of things (IoT), big data, virtual reality (VR), holography, cloud computing, autonomous robots (autorobots), three-dimensional (3D) scanning, 3D printing, and biosensors were established as useful ones to respond to COVID-19. In addition, AI and autorobots could be the most significant technologies of Industry 4.0 in the incoming articles.
Conclusion: These technologies can thus help governments to identify, track, monitor, and treat patients and increase resilience in society and workplace environments during the COVID-19 pandemic.

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Introduction: Considering the importance of identifying and tracing primary sources of Covid-19 crisis in infection control, this study was carried out with the aim of identifying the occupational tasks effective in transmitting Covid-19 in the event of death of a female staff in medical record unit in Shafa Takestan Hospital (Qazvin Province).
Material and Methods: This case study was performed on the death of a 26-year-old married woman working in the medical records department of Shafa Takestan Hospital in March 2019. After identifying and completing the tasks, hazards analysis was performed and finally, various tasks and amount of the Covid-19 sources were determined.
Results: Covid-19 risk sources are classified into three groups of human resources with 51 cases (38.06%), office tools and equipment with 46 cases (34.33%) and paper with 37 cases (27.61%). Four tasks were identified as major tasks with a 59.90% of the total number of COVID-19 risk sources. In this study, two critical tasks were determined with the titles of “reply to requests of forensic medicine and insurance” and “reviewing patients’ surgical reports” that contained a total of 39.06% of the Covid-19 sources.
Conclusion: The results showed that the human resources in two major tasks were the most critical sources of Covid-19. So, the control of these critical tasks is of special importance. The results also showed that it is necessary to transfer the special and unusual tasks to the time after the crisis, in order to reduce the sources of Covid-19 contamination.

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Introduction: This study quantitatively analyzed the fire risk using the Fire Risk Index Method: Multistorey Apartment Buildings (FRIM-MAB) method, considering the importance of fire safety in student dormitories as human gathering centers and previous limited studies.
Material and Methods: This descriptive-analytical study was conducted on 17 sections of the Qazvin University of Medical Sciences student dormitory in 2021. This study used the FRIM-MAB version 2.1. In this method, 17 parameters and their sub-parameters affecting the fire risk index were determined and weighted. Consequently, the studied dormitory was also inspected, the weighted degree of each parameter was computed, and the fire risk index for each section, which ranged between 1 and 5, was determined.
Results: The average fire risk index of the dormitory building at the time of the study was 2.37. The laundry room received the lowest risk index (1.69), while the computer site received the highest risk index (2.7). The results indicated that the most effective parameters causing fire risk were related to “compartmentation” (12 frequency items), “linings in the apartment” (4 frequency items), and “escape routes” (1 frequency item). These parameters contributed more than 42% to create the risk index for the dormitory’s most dangerous areas.
Conclusion: The FRIM-MAB method is a suitable quantitative and indexing fire risk assessment method for student dormitory buildings, and it is a quick, inexpensive, and effective screening and ranking tool. Periodically evaluating the dormitory’s fire risk and, if necessary, improving the environment is essential. In the present study, compartmentation, linings in the apartment, and escape routes were the most effective parameters in fire risk of the studied dormitory.

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Introduction: Fire in hospitals and medical centers can lead to unfortunate and dire accidents due to the immobility of most patients, the presence of expensive medical equipment, and the essential role of hospitals in providing health services to people. This study aims to increase fire safety in a healthcare training center in Qazvin.
Material and Methods: The latest NFPA 101A was used for fire risk assessment in seven departments of an educational hospital in Qazvin City in 2021-2022. The study calculated the residential risk factor for residents of each area, examined fire safety parameters and determined their risk factor, calculated the obtained points of the area under evaluation, determined the minimum required points in different areas of fire safety, and estimated the fire risk level.
Results:  ICU 1 and 2 departments, CCU 1 and 2, central warehouse, pharmacy warehouse, and hospital facilities were selected for fire risk assessment. The ICU building had the best condition with a total fire safety point of 21.1. The facility building, with a total fire safety point of -14.5, was in the worst condition.
Conclusion: The results showed the need for more attention from researchers to conduct studies in outdoor environments, in various parts of the country, on development and validation of novel heat stress indices, and on implementation and evaluation of control measures in environments with high heat stress.