• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.1
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• pp.51-58
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• 2018

Purpose: In this study, through the comparison of the pressure fluctuation and air exchange volume in negative isolation room according to the type of the door and door opening/closing speeds, which is one of the main factors causing the cross contamination of the negative pressure isolation room, establishes standard operating procedures to prevent cross contamination in high risk infectious diseases and isolation room design. Methods: In this study, the air flow each of the room is analyzed using ANASYS CFX CODE for flow analysis. In addition, the grid configuration of the door is constructed by applying Immersed Solid Methods. Results: The pressure fluctuation due to the opening and closing of the hinged door was very large when the moment of the hinged door opened and closed. Especially, at the moment when the door is closed, a pressure reversal phenomenon occurs in which the pressure in the isolation room is larger than the pressure in the anteroom. On the other hand, the pressure fluctuation due to the opening and closing of the sliding door appeared only when the door was closed, but the pressure reversal phenomenon not occurred at the moment when the sliding door was closed, unlike the hinged door. As the opening and closing speed of the hinged door increases, the air exchange volume is increased. However, as the opening and closing speed of the sliding door is decreased, the air exchange volume is increased. Implications: According to the results of this study, it can be concluded that the pressure fluctuation due to the opening and closing of the hinged door is greater than the pressure fluctuation due to the opening and closing of the sliding door. In addition, it can be confirmed that the pressure reversal phenomenon, which may cause to reduce the containment effect in negative pressure isolation room, is caused by the closing of the hinged door. Therefore, it is recommended to install a sliding door to maintain a stable differential pressure in the negative isolation room. Also, as the opening and closing speed of the hinged door is slower and the opening and closing speed of the sliding door is faster, the possibility of cross contamination of the room can be reduced. It is therefore necessary to establish standard operating procedures for negative isolation room for door opening and closing speeds.

• Journal of The Korea Institute of Healthcare Architecture
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• v.29 no.3
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• pp.37-44
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• 2023

Purpose: To decrease cross-infection, it's essential to analyze the spatial composition of the 'PPE doffing area'. Instead of solely relying on manpower standards, we should focus on responding to infectious diseases within the context of space planning. By doing so, we can lower the risk for healthcare workers' infection and ensure a level of safety in various environmental changes or new manpower input situations. Methods: This analysis is conducted specifically for facilities with negative pressure isolation wards. Additionally, interview surveys to obtain feedback from healthcare workers and incorporate their expertise into the design of the 'PPE doffing area' have been carried. Results: In a PPE doffing area, the standard spaces include a PPE doffing room, a shower room, and a clothing room. Depending on the facility environment or the level of infectious diseases, a Decontamination room or Anteroom can be optionally added. Healthcare workers who remove their PPE in the PPE doffing room should avoid re-entering the Negative pressure room. The shower room is often underutilized. When planning for a future PPE doffing area, an aisle space or passageway must be included even if a shower room is planned. Implications: This study examined the space used by healthcare workers rather than patients, with a focus on infection prevention through architectural planning rather than individual efforts. However, the investigation was limited to facilities that have been converted from general wards to negative pressure isolation wards, so it cannot be generalized to all infectious disease facilities.

• Journal of The Korea Institute of Healthcare Architecture
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• v.29 no.4
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• pp.29-35
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• 2023

Purpose: The 2015 Middle East Respiratory Syndrome (MERS) outbreak and the recent COVID-19 pandemic have highlighted the lack of negative pressure isolation rooms and the fragility of the healthcare system. The need for healthcare facility transformation for respiratory infectious diseases has become more prominent due to COVID-19, and the purpose of this study is to provide a foundation for the rapid, economical, and safe construction of negative pressure isolation wards. Methods: This study analyzes the current status of hospitals that have been converted to negative pressure isolation rooms, and provides architectural plans and examples to provide a reference for bedroom change. Research data of this study have been obtained by analyzing the drawings of negative pressure isolation wards of nationally designated inpatient treatment beds and urgent isolation beds. In addition, the relevant literature of urgent isolation beds has been analyzed to derive bedroom change type. Result: In this study, a total of 21 isolation bed conversion methods have been presented. Implications: In order to change efficiently from a general ward to an isolation ward, it is necessary to consider the actual hospital's infectious disease transmission patterns and facility conditions.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.2
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• pp.37-44
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• 2018

Purpose: This study investigates the influences of coughing direction and healthcare worker's location on the transport characteristics of coughed particles in airborne infection isolation room (AIIR), which is commonly called negative pressure isolation room, with a downward ventilation system. Methods: Computational Fluid Dynamics (CFD) was used to simulate the airflow and for tracing the behavior of particles. Results: The results show that the airflow pattern and coughing direction have a significant influence on the characteristics of particle dispersion and deposition. When healthcare workers are in the isolation room with the patient who is lying on the bed, it is recommended to be located far from the anteroom to reduce the exposures from infectious particles. And when the patient is lying, it is more effective in removing particles than when the patient is in Fowler's position. Although it is an isolation room that produces unidirectional flow, coughing particles can spread to the whole room and a large number of particles can be deposited onto patient, bed, side rails, healthcare worker, ceiling, floor, and sidewall. Implications: Following the patients' discharge or transfer, terminal cleaning of the vacated room, furniture, and all clinical equipment is essential. Also, it is necessary to establish detailed standard operating procedure (SOP) in order to reduce the risk of cross-contamination.

• Journal of The Korea Institute of Healthcare Architecture
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• v.27 no.4
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• pp.51-60
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• 2021

Purpose: Tuberculosis(TB) care unit in public health center should be carefully considered to be re-designed as an infection safety environment for both patient and healthcare workers. So, for the enhancement, this study analyses the facility requirements for co-using the screening clinic as a TB and other respiratory disease care unit. Methods: Not only screening clinic facility guidelines from "A Study for Standard Triage Design and Construction Document" but also the guidelines of TB care and related medical facility are reviewed; KDCA, CDC, ECDC and WHO as a TB care, and FGI and NHS for facility. The facility requirements are summarized space, approach, and mechanical requirement in order. By comparing the summary and screening clinic facility guidelines, supplementations are proposed for TB care unit setting. Results: The result of this study shows that both the space program and mechanical requirement of the screening clinic and that of TB care unit are almost identical and could be share, which include direct airflow or negative air pressure in an exam room. To increase functional and economical efficiency, however, it is necessary to consider a multi-functional negative pressured room, So care process may be re-designed based on a room type; face-to-face room or glass wall inbetween. Implications: The facility guidelines for TB care unit of a public health center should be developed to build a safe environment for infection control by reflecting its medical plan and budget.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.33 no.12
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• pp.19-28
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• 2017

The purpose of this study is to propose a design methodology to build temporary isolation rooms when infectious diseases suddenly occur in a certain region, such as the case of MERS-Cov in South Korea in 2015. Although most big hospitals usually have isolation rooms, they are expensive and dangerous to run such facilities on normal and typical days. To deal with these problems in this research, shipping containers are chosen as devices used to build the temporary isolation rooms near the original hospital. To do so, firstly, a prototype for the temporary isolation room was designed with the three part modules. The first part is for the medical team; the second part including the isolation rooms is for patients; the third part is for medical selection rooms to test the specimens. Secondly, the plan was compared with the MERS-Cov infection control guidelines. Finally this prototype is applied into the Yong-in Yon-sei severance hospital and then evaluated through a CFD simulation using STAR-CCM+(ver.9.06) for checking infectious bacterium movement in this prototype. The result showed that the prototype is effectively safe for patients tested as negative, patients waiting to be tested, and the medical team.

• Journal of Yeungnam Medical Science
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• v.39 no.3
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• pp.223-229
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• 2022

Background: The first large coronavirus disease 2019 (COVID-19) outbreak outside China occurred in Daegu. In response, we developed infection prevention measures for surgical patients during the outbreak at our hospital and retrospectively reviewed the outcomes of COVID-19-related surgical patients. Methods: We reviewed the medical records of 118 COVID-19-related surgical patients and monitored their clinical outcomes until March 31, 2021. We also interviewed healthcare workers who participated in their perioperative care at Kyungpook National University Chilgok Hospital. The perioperative management guidelines for COVID-19-related patients were prepared through multidisciplinary discussions, including the infection control department, surgical departments, and anesthesiology department before and during the COVID-19 outbreak. Results: One standard operating room was temporarily converted to a negative-pressure room by increasing the exhaust air volume, creating a relative pressure of -11.3 Pa. The healthcare workers were equipped with personal protective equipment according to the patient's classification of the risk of COVID-19 transmission. The 118 COVID-19-related patients underwent emergent surgery in the negative-pressure room, including three COVID-19-confirmed patients and five COVID-19-exposed patients. Conclusion: All surgeries of the COVID-19-related patients were performed without specific adverse events or perioperative COVID-19 transmission. Our experience setting up a negative-pressure operating room and conservative perioperative protocol to prevent COVID-19 transmission will help plan and execute infection control measures in the future.

• Journal of The Korea Institute of Healthcare Architecture
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• v.28 no.2
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• pp.17-29
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• 2022

Purpose: In terms of efficiency and safety, this study attempted to organize data on the operation methods and architectural planning of infectious diseases hospitals. Methods: The results obtained through on-site and interview surveys with hospital officials and medical staffs at four infectious diseases hospitals under construction were summarized based on those original business plans and facility guidelines. Results: First, the operational methods to secure safety and operational efficiency were summarized for each department which are major hospital functions of infectious disease hospitals. Second, as the architectural planning, the characteristics of space and circulation of each department are summarized. For safety of medical staff, negative pressure and non-negative pressure zone have to completely separated. In addition medical staff wears PPE and enters the negative pressure zone and returns in the order of admiral, shower, and gowning in the PPE undressing room after patient treatment. In case of operational efficiency, flexible operation is required in normal and crisis situations. For example, it is important for The Ward to gradually switch to negative pressure beds in times of crisis from normal situation and the outpatient department considers the composition of negative pressure and non-negative pressure outpatient spaces that can operate in parallel even in crisis situations. Implications: Infectious disease hospitals require flexible operation and appropriate facilities for normal and crisis situations.

• Journal of The Korea Institute of Healthcare Architecture
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• v.29 no.4
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• pp.69-77
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• 2023

Purpose: During the COVID-19 pandemic, there have been many cases of converting regular hospital wards into temporary negative pressure isolation wards. The purpose of this study is to evaluate the minimum airflow differences that satisfies the pressure difference criteria(-2.5 Pa) according to airtightness of switching type wards, in preparation for utilization of aging regular wards as negative pressure isolation wards. Methods: Visual inspection and field measurements were conducted using blower door to evaluate airtightness of 5 hospital wards. CONTAM simulation was used to assess the airflow differences when pressure difference between the corridor and wards met the criteria at various levels of airtightness. Results: The ACH₅₀ of evaluated wards ranged from 19.3 to 50.1 h^-1 with an average of 37.0 h^-1, indicating more than four times leakier than other building types. The minimum airflow differences increased as the airtightness of the wards decreased and the size of the wards increased. Implications: When operating rapidly converted negative pressure isolation wards, understanding airtightness is crucial for determining the minimum airflow differences to maintain the pressure differences. The analysis of this study suggests that improving the airtightness of aging rooms is essential and the minimum airflow differences should be suggested considering both the airtightness and size of rooms.

• Journal of Ocean Engineering and Technology
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• v.9 no.1
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• pp.111-119
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• 1995

The elastic-plastic fracture toughness($J_{IC}$) and fracture resistance (J-R curve) of SA508-3 alloy steel used for nuclear reactor pressure vessel are investigated by using CT-type specimens. Fracture toughness tests are conducted by unloading compliance method and multiple specimen method at room temperature, -2$0^{\circ}C$ and 20$0^{\circ}C$. The apparent negative crack growth phenomenon which usually arises in partial unloading compliance test is well known. The negative crack growth phenomenon in determining J sub(IC) or J-R cure from partial unloading compliance experiments may be eliminated by the offset technique. In this study, the evaluation of $J_{IC}$ multiple specimen method recommended by the JSME gives the most reliable results by using half-size CT(similar-type) specimens.