Air Quality of Private Interiors during the COVID-19 Pandemic: A Case Study of Dormitory Interiors as Shared Spaces

Abstract

COVID-19 was a wake-up call for many researchers and designers that encouraged them to create better interiors. Keeping air quality within safe standards is fundamental and the best strategy to stop the spreading of viruses. Being aware of the severity of indoor transmissions of infections, exploring and understanding how they are spread, and how to avoid them can be critical steps to enhance public health. However, many of the private spaces, residential areas and places where multiple people accommodate together remain unattended, such as dormitory buildings. Since many of them do not have an HVAC system, natural ventilation is the primary method for airing dormitory rooms. Therefore, this study aims to reveal existing ventilation conditions in university dormitories, occupants’ behaviors, disinfection, and air cleaning methods in wintertime. For this, a dormitory complex was selected in Ankara (Turkey), whose climate can be compared to many other cities in the northern hemisphere, as an initial case study to provide insight. Overall, it was found that window-opening behaviors of university students are mostly determined by the density of their rooms. The study findings will raise awareness and motivate further studies in architecture, interior architecture, and design disciplines and provide initial knowledge about the topic.

1. Introduction

Infections caught in buildings are a major global cause of sickness and mortality [1] (p. 271). According to this striking estimation obtained by Sundell [2] “more than half of the body’s intake of air during a lifetime is inhaled indoors” and it is well known that interiors that surround our lives both physically and mentally have significant effects on our health and well-being. COVID-19 was a wake-up call for many researchers and designers/architects that encouraged them to design and reveal better interiors due to national lockdowns and the novel regulations of the “new normal”. Keeping air quality within safe standards is fundamental and the best strategy to stop the spreading of airborne viruses, not only for COVID-19 but also for all airborne diseases. Proper ventilation might guarantee safe interiors if it is performed frequently. Before COVID-19, air filtration and air disinfection were not used in almost any public building, except healthcare facilities, against the transmission of airborne infections [3,4,5]. With the COVID-19 outbreak, it has become more apparent that the reliance on conventional building HVAC systems needs to be revisited to minimize the spread of the COVID-19 virus [6,7]. Being aware of the severity of indoor transmissions of infections, exploring and understanding their spreading ways, and how to avoid them can be a critical step to enhancing public health. Due to the novelty of the COVID-19 pandemic, current knowledge of indoor transmission and methods for avoiding its spread remains poor.

Even though there are effective technologies and methods to minimize the spread of airborne droplets in interior spaces which are “ventilation, high-efficiency air filtration, ionization of the air, environmental condition control, ultraviolet germicidal irradiation, non-thermal plasma and reactive oxygen species, filter coatings, chemical disinfectants, and heat inactivation” [8], still, the occupants’ behaviors could play a major role in avoiding or permitting the spread of the COVID-19 virus. Moreover, some technologies and methods are not available to the majority of interior occupants, therefore, passive natural methods and occupants’ engagement with them still hold the utmost importance for public health in public and private interiors. Dormitories are exceptional interiors as a typology: both residential/private interiors and shared/public interiors as high-density spaces [9], they function as private interiors in high-density public spaces. With the beginning of the “new normal”, various public spaces spent significant efforts to avoid the spread of airborne droplets by installing and/or maintaining their HVAC systems. However, many of the residential areas and places where multiple people accommodate together remain unattended. One of the unattended places that need urgent consideration is the dormitory buildings. Like many other public spaces, most of the dormitory buildings worldwide were closed for months and began to reopen months after, in line with the new regulations [10,11].

Dormitory rooms can be called “enclosed spaces” since many of them do not have an HVAC system that can be ventilated with a preference left to the users. Without a centralized ventilation system, the airing of the dormitory rooms became more significant during the pandemic. As Bazant and Brush [12] and many other authorities highlighted, for the COVID-19 virus, the dominant mode of infection is by airborne transmission. Thus, the importance of ventilation and its effect on physical comfort and health in interiors have been rediscovered with the current pandemic [13,14,15,16]. According to the systematic review that Fadaei [16] conducted, the role of ventilation in mitigating COVID-19 spread in indoor air environments showed that parameters such as “ambient wind, air recirculation and rate of ventilation, aerosols, relative humidity, and temperature” were commonly studied. However, none of them was especially focused on dormitory environments and they did not examine the subjective disinfection and air cleaning methods of occupants.

Since many of the dormitory buildings do not have an HVAC system, natural ventilation is the primary method for airing the interior spaces. During summer, natural ventilation is possible and commonly used in those shared areas, but in winter it is not always possible to use natural ventilation. The occupants’ behaviors such as window-opening behaviors, using portable air conditioners and their cleaning routines share an important part in disinfection and air cleaning methods in combating the virus. Since opening (and closing) windows has a considerable effect on interior spaces’ air change rates [17,18,19] and diminishes the spread of airborne droplets, examining the window-opening behaviors of university students accommodating in dormitories can be vital. Various important studies were conducted concerning window-opening behaviors in numerous interior typologies such as residences, schools, offices and dormitories (e.g., 16 German offices by D’Oca and Hong [20] and a dormitory building from Japan by Schweriker, Haldi, Shukuya, Robinson [21]), however, a study concerning both the dormitory rooms and the pandemic times has not been conducted yet. For instance, Andersen, Fabi, Toftum, Corgnati, Olesen [22] focused on residential areas in their study. This long-term study covered 15 Danish houses and as their results revealed, indoor CO₂ rate and outdoor air temperature are the most significant factors in window-opening (and closing) behaviors. Another similar study explored high-school classrooms in Italy [23] and their conclusions were similar to Andersen et al.’s [22] results. To discover the patterns of window-opening (and closing) behaviors, a study was conducted in 16 German offices by D’Oca and Hong [20]. Likewise, in other studies, their results also highlighted the role of factors such as indoor air temperature, outdoor air temperature, time of day, and occupancy in window-opening behaviors [20]. Schweriker, Haldi, Shukuya, Robinson [21] collected data concerning window-opening behavior from three residential areas located in Switzerland and a dormitory building in Japan. The outdoor air temperature was found to be the most effective factor in determining window-opening behavior. As mentioned previously, a study concerning both the dormitory rooms and the pandemic times has not been carried out yet. Thus, this study focuses on university students’ strategies for ventilating their dormitory rooms in wintertime. Also, perceiving the presence of sunlight as a disinfection method for COVID-19 droplets needs to be examined because the World Health Organization refers to sunlight in guidance on preventing hospital infections and it is known that vitamin D has an important role in the functioning of the immune system [1,24]. Some of the most common indoor air pollutants that can affect air quality in student dormitories are formaldehyde (often found in construction materials), mold, dust and dust mites, and Volatile Organic Compounds (VOCs). In addition to common indoor air pollutants, the air quality in dormitories should also be examined in terms of the spread of the COVID-19 virus. Therefore, this study aims to highlight the importance of individual methods for disinfection and air cleaning against both the COVID-19 virus and other airborne diseases. This study focused on the window-opening behavior, presence of sunlight, dryers and humidifiers, green area, use of chemicals and density in university dormitories. For this work, a dormitory complex was selected from Ankara, Turkey as a case study for the wintertime.

2. Materials and Methods

2.1. Case Study

Bilkent University Dormitories (Ankara, Turkey, 39°55′ N 32°51′ E) host approximately 4600 students [25] with its 26 buildings (the dormitory buildings vary from 4 to 11 floors) which are mostly located at the main campus. Ankara was selected as a case city due to its climate and harsh winter conditions [26], which many European, Asian and American cities might have in the northern hemisphere during wintertime thus providing an ideal case for the scope of this study and the availability of several high-density campuses in the city. Bilkent dormitories offer single, double, triple and quadruple rooms as well as suite rooms thus enabling a variety of dormitory rooms with a different number of users which can correspond to several worldwide interior schemes in other cases with similar climates. The floor areas of the dormitory rooms vary between 6 and 30 m² and have a height of 3–4 m. Figure 1 shows a typical plan of a four-story dormitory building consisting of single rooms (approximately 6 m²) only in which the bathrooms, toilets and kitchen are located at the center. There are also bigger kitchens and common recreational areas at the end of the building (See Figure 1).

All the rooms were furnished with basic furniture such as bedsteads, wardrobes, work desks and bookshelves [25]. As can be seen via the link http://yurtlar.bilkent.edu.tr/tr/76-tek-cift-kisilik/#bwg6/327 (accessed on 21 December 2021) the exterior view of a five-story dormitory building, the windows are rectangular and repetitive. There is one window in each dormitory room (See http://yurtlar.bilkent.edu.tr/tr/76-tek-cift-kisilik/#bwg6/330 (accessed on 21 December 2021) for the interior of a five-story dormitory building) and only one wing of these windows can be opened.

In addition to rooms, there are also common areas for the use of the students such as a kitchen, laundry, bathrooms and toilets, television room, study rooms and game rooms. The dormitories are heated by central heating and hot water is provided 24 h a day. General cleaning of all dormitories is carried out regularly by ISO-certified private cleaning companies following health and hygiene rules. ISO standards for Quality Management (ISO 9001), Health and Safety Management (ISO 45001) and Environmental Management (ISO 140001) are used to provide high-quality services, ensure safety by minimizing risks and engage in eco-friendly practices. More detailed cleaning of student rooms is carried out less frequently which includes washing the sheets, pillowcases and duvet covers [25].

Since the case study approach allows in-depth, multi-faceted explorations of complex issues in their real-life settings [28], this study adopted a case study approach for exploring the air quality in dormitory rooms in the everyday context in which they occur normally. Based on the literature review, it was determined that the air quality in dormitory rooms has been investigated by adopting a case study approach, and most of these studies were conducted in China [29,30,31,32]. Expanding case studies to include other countries can provide a broader understanding of the topic. Considering these previous studies were mostly conducted before the COVID-19 outbreak, further case studies would underpin the existing literature and reveal the “new normal”.

2.2. Survey

This study employed a survey to explore students’ self-reported behaviors and perceptions with these main points focusing on natural ventilation: window-opening behavior, presence of sunlight, dryers and humidifiers, green area, use of chemicals and density in university dormitories.

A survey consisting of 32 questions (both open-ended and multiple-choice questions) (See Appendix A) was formed by the authors who are professionals in the field of architecture and building design. The survey was distributed to participants with an e-mail invitation in December 2021 when winter conditions are harsher and while pandemic conditions are still valid, so the participants’ perspectives were taken as basis. The survey was formed through a web-based survey tool offered by Google. The survey questions were in the primary languages (English and Turkish) of the participants. After providing participant information and a consent form, the survey asked demographic questions including age and gender. Following the demographics, several questions were asked to gather detailed information about the dormitory building and dormitory room such as the total number of floors that the dormitory building has, floor area and height of the dormitory room, the number of people that the participant shares their room with, the number of windows in the room, their positions and which direction they are facing, the view from those windows and the materials used in the dormitory rooms. Several questions were asked to gain information about the daily habits of the participants when in their rooms and window-opening behaviors (such as “How many times do you leave the room? For how long?”, “How many hours you spend in this dormitory room in a day?” and “How often do you open your window in a day in the wintertime?”). The rest of the questions were about disinfection methods and natural ventilation habits in wintertime against the spread of airborne droplets.

2.3. Sampling from Bilkent University Dormitories

A total of 106 students mostly aged between 18 and 24 (54 female, 50 male and 2 prefer not to reveal their gender) accommodating in Bilkent University Dormitories voluntarily participated in the study. The survey was sent to all students staying in the dormitories via Bilkent Dormitories Directorate with an e-mail invitation in December 2021. They were all informed about the study’s process with a participant information form at the beginning of the survey.

Descriptive analysis and Pearson’s Correlation tests were conducted by IBM SPSS 27.0.

3. Results

3.1. Findings from Bilkent University Dormitories

The findings provided detailed information about the density in the dormitory rooms, daily habits, window-opening behaviors in wintertime, usage of dryers and humidifiers, usage of chemicals, perception of sunlight as a disinfection method against airborne droplets, the presence and the proximity to the green areas.

According to the findings from the participants’ behaviors, most of them leave their dormitory rooms for 6–8 h only to attend their classes and they spend the rest of their days in their rooms except for basic needs. A minority of participants leave their rooms multiple times a day for shopping, eating, smoking and socializing. Speaking more concisely, 72% of participants spent more than 8 h in their dormitory rooms. A total of 25% of participants live alone in their dormitory rooms, whereas 34% of them share their rooms with one person, 18% share with two people, 16% share with three people and 7% share with four people. Bilkent University dormitories have buildings with different types of story heights from 4 to 11 floors and different conditions (See

Table 1. Table showing the conditions of the dormitory buildings and rooms.

The floor where the room is located	Ground—10% First—23% Second—25% Third—13% Fourth—19% Fifth and above—10%
Room surface material	Ceramic tile—50% Wooden parquet—47% Carpet—5%
The direction the windows in the room face	North—24% South—20% East—13% West—14% Not specified—29%
Number of windows in the room	1—52% 2—41% 3—7%

). Participants were also asked to provide their perceptions about the ratio of all windows’ area to the whole floor area of the dormitory room which affect the air quality (See Figure 2).

The survey also asked further questions about the overall view through the windows in the dormitory rooms, seeing a greenery area when looking through the windows, the presence of green areas in the dormitory building and a walking distance of the dormitory building, and the presence of plants in the room. The vast majority of respondents report access to green spaces outside their dormitories, while relatively few have plants inside (See

Table 2. Table showing the conditions of view and plants in dormitory buildings and rooms.

The overall view through the window(s) in the room	None—30% Some—39% Heavy—31%
Green areas are observed through window(s)	91%
Dormitory contains green areas	55%
Green area in walking distance	99%
Rooms with plants	8%

).

It is important to highlight that the presence of a nearby greenery area enhances the sense of restoration, increases the fresh air and reduces indoor air pollution [33]. Especially in dormitory rooms like the other indoor spaces where most of daily life is spent, a decline in indoor air quality has an impact on people’s performance and health [34,35,36]. Thus, in addition to the ventilation of the rooms, the presence of plants can also help improve air quality.

3.2. Disinfection and Air Cleaning Methods—Bilkent University

As this study focused on gathering information about the window-opening behaviors and individual methods that university students applied to avoid airborne droplets in their dormitory rooms, twelve detailed questions were asked about disinfection and air cleaning methods. A total of 53% of participants did not perceive the presence of sunlight as a disinfection method for COVID-19 droplets. Of the remaining respondents, 23% of participants perceived the presence of sunlight as a disinfection method and 24% of participants could not decide whether the presence of sunlight was a disinfection method for COVID-19 droplets. The majority of participants perceive “natural ventilation” and “regular cleaning” as the most effective disinfection methods for COVID-19 droplets. A total of 55% of participants prefer only using natural ventilation as a disinfection method, 7% of them prefer mechanical ventilation and 33% prefer to use both whereas 5% of participants did not use any of them. Participants report a variety of results in window-opening in a day in wintertime (See Figure 3). The majority of participants open the windows in their dormitory rooms at least 1–2 times per day for natural ventilation.

When examined in detail, for the ones who use natural ventilation as a disinfection method in a day, 24% of participants only open their window(s) in the dormitory room for less than 10 min (See Figure 4). Overall, the majority of participants who use natural ventilation as a disinfection method in a day open their windows for less than 30 min per day.

Most of the participants did not do the cleaning themselves and they preferred the staff to clean their rooms. The ones who do the cleaning themselves mostly prefer to use chemicals and cologne (a widely used unique hand sanitizer in Turkey) for the disinfection. Only 9% of participants had a black mold problem in their dormitory rooms, and they were wiping the black mold thoroughly with bleach, trying to dry the wall and reduce the moisture in the air. A total of 43% of participants use dryers for the laundry (i.e., hanging their wet clothes) in their dormitory rooms, however, none of them use a dehumidifier or air purifier in their rooms in wintertime even if they had a black mold problem.

4. Discussion

The dormitory room floor areas at Bilkent University vary between 6 and 30 m² and 75% of the students share their rooms with at least one person which makes the airing and disinfection of the room important. According to available evidence, the infection spreads between people when an infected person is in close contact with another person [11]. Due to the high density of people in dormitory rooms, close-range contact is more likely to happen which, unfortunately, may increase the chance of being in contact with the infected person if there is any in the environment. Also, as the survey results showed, 72% of university students spend more than 8 h in their dormitory rooms. If the room is not well ventilated, meaning that there is not enough fresh air coming in and stale air going out, the concentration of CO₂ can build up over time and the risk of COVID-19 spreading can increase [13,37]. In addition to the people who are infected, the materials in the dormitory rooms can also spread infection. This is because the infection can be transmitted not only by “contact” with the sick people, but also by the surfaces that have been exposed to their cough or sneeze [1,38]. Thus, such surfaces can be risky for contamination, especially the ones that cannot be deep cleaned regularly such as carpets. Only 5% of dormitory rooms in Bilkent University have a carpet on the floor surface which can be easily contaminated. The usage of ceramic tiles and wooden parquets is easier to maintain than carpets.

4.1. Current Status of Air Quality in Bilkent Dormitories

There is evidence that fresh air and sunlight penetration in buildings can diminish the transmission of airborne pathogens [1,39,40]. The presence of at least one window can sometimes be sufficient for proper ventilation, however, more attention should be paid to the ventilation rate. In this manner, the total window to dormitory room floor area ratio becomes more important in determining air quality. When examined in detail, a majority of the windows in the dormitory rooms (39%) at Bilkent University have a 10–20% ratio according to the whole floor area (See Figure 2) which affects the ventilation rate in the interior of the dormitory rooms. According to current standards in residential areas [1,41], 10 L/s/person is the minimum recommended ventilation rate for diminishing the spread of infection, and for the dormitory rooms, the ventilation rates should be calculated to reach the “probability of infection calculations” [8] (p. 2). However, for this study, the other parameters (such as breathing rate, air change rate, etc.) determining ventilation rate could not be collected since an online survey was selected as the methodology to minimize human interaction.

4.2. Perceptions of Sunlight and Natural Ventilation as Disinfection Methods for COVID-19

Also, sunlight penetration in buildings is known as an effective method for avoiding the transmission of airborne pathogens [42]. According to the survey results, more than half of the participants (53%) did not perceive the presence of sunlight as a disinfection method for COVID-19 droplets. Correspondingly, 24% of participants could not decide whether it is a disinfection method. According to the experiments focusing on the effect of sunlight on the inactivation rate of the COVID-19 virus, the half-life of aerosolized SARS-CoV-2 is approximately 86 min in simulated saliva in dark conditions [42] (p. 3). Also, the presence of high-intensity sunlight (such as in summer) was found to reduce the infectious concentration of the virus up to 90% after 6 min. Azuma et al. [42] (p. 3) also highlighted the effect of the low-density sunlight; “Even with the low-intensity sunlight-simulated late winter or early fall, a 90% reduction was observed after 19 min”. Thus, the findings pointed out that sunlight is “useful in mitigation strategies to minimize the potential for aerosol transmission” [42] (p. 3) and [43]. It was expected that sunlight was perceived as one of the effective methods for disinfection by university students, however, only 23% of them perceive it as such. Possibly their perceptions would differ for spring and summer times since the effectiveness of sunrays become stronger. In any case, the reasons for this should be investigated in a more detailed way for combating the virus more effectively and students should be informed about this issue.

More than half of the participants prefer using only natural ventilation as a disinfection method (55%) which emphasizes that the window-opening behavior should be examined in detail. According to correlation coefficient functions, a low positive correlation (r = 0.228, p = 0.019) was found between the frequency of opening a window during the day in wintertime and the number of people who shared the dormitory room (See

Table 3. Table showing Pearson’s Correlations for window-opening behaviors.

Variable		Freq. of Opening Window in a Day in Wintertime	Window-Opening in Minutes during a Day in Wintertime	Ratio of All Windows’ Area to the Whole Floor Area	The Direction the Window Faces	Number of People Shared
Freq. of opening window in a day in wintertime	Pearson’s r	—
	p-value	—
Window-opening in minutes in a day in wintertime	Pearson’s r	0.053	—
	p-value	0.589	—
Ratio of the all windows’ area to the whole floor area	Pearson’s r	0.093	0.051	—
	p-value	0.344	0.605	—
The direction the window faces	Pearson’s r	0.114	−0.185	0.015	—
	p-value	0.246	0.058	0.877	—
Number of people shared	Pearson’s r	0.228	−0.007	0.065	0.153	—
	p-value	0.019	0.944	0.509	0.117	—

). This correlation showed that university students tend to open their windows more as the number of people sharing the same room increases. As was indicated in several previous studies [20,21,22,23] window-opening behaviors are usually related to indoor CO₂ concentration which can be directly related to the number of people occupying an interior space. Thus, as this survey’s findings indicated, the density of dormitory rooms affects people’s window-opening behaviors. Also, the outdoor air temperature and time of the day are the other determinants for window-opening behavior [44]. Natural ventilation did not always get the attention it deserved. “In 1894, it was noticed that exposure to fresh air appeared to reduce the virulence of the tubercle bacillus. In the 1960s, the lethality of outside air to micro-organisms was rediscovered and the term open-air factor (OAF) was introduced” [1,45,46]. For the case of Bilkent University Dormitory, the outdoor air temperature can be one of the strongest determinants (for students not to show window-opening behavior) since the average temperature in Ankara in December is 2.5 °C [26]. However, a significant correlation between the outdoor air temperature, the direction the windows face in dormitory rooms, window-opening times (in minutes) during a day in wintertime, and the ratio of all windows’ area to the whole floor area could not be detected (See Table 3).

Current British guidance recommends passive natural ventilation rather than air-conditioning or mechanical ventilation in hospitals [1] because of mechanical ventilation’s inadequate maintenance. The same can be valid for dormitory buildings since detailed cleaning is infrequently performed. From the survey results, it can be concluded that students did not prefer to use a dehumidifier and/or air purifier in their rooms even if they had a black mold problem (9%) because they may not maintain a regular cleaning. Also, it was found that relative humidity had no significant effect on the survival of the aerosolized virus [42]. Thus, the dehumidifier can only be used to avoid black mold formation in a dormitory room.

The value of having physical and/or visual access to green areas has increased with the COVID-19 breakout since such areas easily allow social distancing and recreation during lockdown times. Access to green areas is easy for all the students staying in Bilkent University Dormitories (99% of buildings were very close to a green area) and 91% of students can see a greenery area from their dormitory rooms (See Table 2). As Kleinschroth and Kowarik [39] highlighted having visual access to a green space alone can be beneficial. Green areas encourage both physical and psychological well-being by providing spaces for exercising and socializing regularly, which consecutively improves general well-being and ability to cope with infections [42] (p. 319). Thus, especially in dormitory areas, green areas can be utilized as a tool during and post-pandemic periods.

4.3. Limitation and Future Work

The study was limited to students who were willing to participate in this study. It can be anticipated they represent the most engaging group about air quality in this interior typology. Ergo, even though their engagement was an opportunity during the research process, it is inferred that other users have less awareness which is an alarming situation. On the other hand, access to these interiors, since they are private interiors, was limited and the study embraced online methods with the restrictions of COVID-19. Further discussion about natural ventilation behavior and reflection on users’ daily routines is needed for future studies since there is limited discussion about users’ experience and commitment to systematic ventilation of interiors in the literature.

For future studies, more detailed data should be collected such as measurements of air quality, infectious agents on surfaces or in the air. Also, further studies should be conducted to explore the window-opening behaviors of students who are accommodated in dormitories. More dormitories from different geographical locations should be studied. For more measurement-based studies, gathering information about breathing rate, air change rate, etc., to calculate the “probability of infection” in university dormitory rooms can be advised.

5. Conclusions

This study aims to highlight the importance of the methods that individuals apply for disinfection and air cleaning against COVID-19. Minimizing the indoor transmissions of airborne infections, thus enhancing public health can be possible with the participation of everyone. Dormitory rooms were investigated to reveal occupants’ behaviors in high-density private spaces and in high-density campuses, which can be a common case in many cities. Although previous studies revealed extensive reviews of ventilation systems, users’ behaviors in dormitory interiors had not been explored before. The study investigated users’ behaviors in dormitories regarding natural ventilation in relation to airborne viruses and user awareness. Users’ awareness and behaviors are fundamental to improving air quality in all interior types and natural ventilation, as a recommended sustainable ventilation method depends on users’ behaviors. By doing so the study provides insight into overlooked dormitory interiors which are shared private interiors where multiple people accommodate and are in between public space and residential spaces.

Overall, it was found that in dormitory rooms natural ventilation is the primary source of disinfection and air cleaning methods. Among other determinants, window-opening behaviors of university students are mostly determined by the density of their rooms. So, they tend to open their windows more as the number of people sharing the same room increases. Generally, it may be suggested to decrease the density of occupants in a dormitory room, and it may be recommended to use an appropriately sized air filter, which is known to be effective in the removal of airborne droplets, in addition to effective natural ventilation and acquiring this window-opening behavior, especially for small-sized dormitories [8] (p. 9).

It is possible to minimize the hazardousness of airborne droplets by making wise design decisions and embracing good design practices, which first starts with understanding the behavior of users. As a new way of thinking is required with the outbreak of COVID-19, reconsidering new ways of designing now becomes a must. Thus, this study can be an important step for understanding the users’ needs and individual methods and designing accordingly. Study results will be helpful in defining ventilation strategies and preparing a framework for future studies whose purpose will be designing innovative and sustainable interiors.