1. Introduction
The COVID-19 pandemic persistence is exposing the vulnerability of urban systems [
1] and, in particular, our built environment [
2]. Given the share of daily life that most of humans spend indoors [
3], the buildings design and construction practices as well as the management of buildings confined spaces are currently put into question.
Although architecture was born as a means for humankind to be safe from hazards, the built environment currently represents a collector of potential transmission vectors for the spread of the SARS-CoV-2 [
2,
4,
5]. Hence, it has an important role to play in supporting public health measures and reducing the risk of infections [
6]. Adequate research is therefore needed to investigate the strategies that could mitigate the spread of the epidemic, developing new prevention solutions to reduce the risks of direct exposure between individuals [
7,
8]. Especially in crowded places, the virus can be transmitted through different means [
9], such as airborne pathways—aerosol and droplets—and through both direct and indirect contact with contaminated surfaces, namely fomites, even though this latter kind of transmission seems to have a minor impact on the spread of the virus [
5,
10]. Therefore, with the pandemic outbreak, the sudden need to manage the shared indoor environments was the most urgent difficulty to address, a concern that mainly involved three strategies:
The management of indoor air quality and heating, ventilation, and air conditioning systems (HVAC) through the increase in the air change rates or the introduction of filtering components and purification technologies as a means to reduce the transmission of infectious diseases;
The reorganization of functions and activities in public and private buildings on various scales: from managing communal areas in multiusers complexes and workplaces, to arranging hotels guaranteeing isolation during quarantine, to completely revolutionize healthcare facilities [
9,
11,
12];
Encouraging proper behaviors in the users of public and private buildings open to the public through fostering sanitizing practices and regulating their flows inside buildings, especially in activities potentially subject to crowding, such as supermarkets, shopping centers, restaurants, and cultural or leisure facilities.
Due to the indoor prevalent airborne transmission [
5,
10,
13], many of the adaptive measures in buildings focused on air quality and HVAC improvements [
9,
14,
15], and the most significant updates in design requirements have been an increase in natural ventilation and air-change rates in crowded or communal rooms [
16]. However, other than engineering control, less-analyzed transmission pathways, such as fomites, should also be considered and addressed to reduce the virus spreading [
4], as a single strategy or implementation might not be enough to reduce the exposure to the virus [
17]. Such investigation would require a multidisciplinary approach [
6], fostering systemic studies on the COVID-19 response in the built environment [
8].
In fact, the disruptive changes brought in by the alternative management of indoor environments altered our everyday patterns and activities [
18]. Social distancing and the regulation of flows also turned into common prevention measures to avoid crowding [
19], a circumstance that can raise SARS-CoV-2 transmission risk by increasing interpersonal contact frequency and duration [
2]. In this context, balancing the need for control measures and the open-access design concept appears essential [
7], and the use of procedures and administrative controls can contribute to a safer building environment [
8]. Social distancing, which requires clear and consistent communication [
20], can be considered a design issue [
15], and the spatial configuration of buildings plays a major role in encouraging or discouraging adherence to new interaction policies due to the pandemic [
4]. Hence, in the pandemic context, spatial design—meant as a conceptual design approach accounting for both the interior and service designs—can also improve indoor air quality by managing people’s flows in interiors [
9]. In this sense, the future design practice will somehow need to reduce close person-to-person contacts in a risky indoor environment by facilitating behavioral changes and adherence to protocols [
1,
14] while considering social identity as well [
19]. In this perspective, architectural spaces should be conceptualized and developed with clear goals [
7]. As the contemporary built environment requires adaptive measures to confront the current health necessities, design strategies aiming to plan circulation routes and allowing the efficient displacement of the users’ flows reduce exposure to the virus and provide advantages in ensuring regular indoor activities as well [
16].
As both actors and beneficiaries, users play a key role in planning anti-COVID strategies. Their decisions are deeply influenced by the perceived risk [
21,
22], and as a health emergency, the pandemic is connected to considerable psychosocial consequences [
23] affecting individual behaviors.
In these circumstances, mitigation and prevention strategies are only successful if users are committed to follow health protocols [
24]. Therefore, research on implementing anti-COVID-19 safety measures would also benefit from the users’ feedback to assess and improve the effectiveness of the implemented measures [
19,
25]. Previous studies already adopted this approach. For example, Stirapongsasuti and colleagues [
26] focused on improving hand hygiene habits in private organizations, developing hand-sanitizer systems that respond to the user’s behavior. Another research investigated the attitudes of users towards the thermoscanner as a large-scale, rapid measurement method of people’s temperatures, as fever could be one of the early symptoms of COVID-19 infection [
27]. However, limited information is available about individuals’ confidence in different strategies [
19] all together.
Starting from these premises, and learning from almost two years of the pandemic, we began a research investigating individuals’ perception of the anti-COVID measures commonly implemented in buildings. The goal of the research was to provide a “lesson learned” supporting both the definition of novel design and management strategies to be implemented in the built environment and the identification of the appropriate characteristics of the prevention devices and wayfinding systems.
Therefore, the research focused on how users perceived, on the one hand, the risks deriving from the virus in indoor environments and, on the other, the related prevention measures to understand how they influence people’s behavior [
28].
The aims of the research were:
Understanding in depth, through both the psychological and architectural perspectives, how users perceive the anti-COVID strategies carried out during the pandemic, focusing on the physical elements (devices and wayfinding systems) commonly used to implement them in buildings;
Identifying the design features of these elements that could enhance people’s awareness and promote their appropriate behavior and to define guidelines supporting the design of the anti-COVID prevention systems so that they could improve the users’ consciousness and induce the appropriate behaviors.
Due to the multidisciplinary nature of the research, the investigation approach adopted a twofold perspective involving both psychology and architectural design researchers.
In more detail, the research investigated two main topics:
The type and organization of the prevention measures implemented by several facilities entrance(s) and in the interiors, examining the objects/devices with sanitizing and monitoring purposes and the wayfinding systems used to regulate the users’ flows and distancing;
The users’ perception of the mentioned prevention measures supporting the anti-COVID protocols.
2. Materials and Methods
The research investigated the most common measures adopted during 2020 and 2021 in Italy, specifically in the Veneto region, to prevent SARS-CoV-2 transmission inside buildings. Public and private facilities open to the public were involved, with all of them located in the provinces of Padua and Venice. The choice of the specific categories, activities, or businesses depended both on their large degree of diffusion in the territory and on their high attendance, two features making them significant in managing and limiting the related chances of SARS-CoV-2 infection. On one hand, the research investigated businesses and activities pertaining to different categories:
Retail (both food and non-food);
Covered open-air retail (market halls);
Catering (restaurants and bars);
Personal service activities (hair and beauty salons);
Private and public offices open to public.
On the other hand, it also considered two large and complex public buildings due to the particular conditions in managing the users’ flows during the pandemic:
Four different methods were used for investigating the two research topics.
Observational field surveys: To understand how the prevention methods were implemented in public and private buildings, field surveys were carried out to identify and classify the different adopted systems. This survey concerned several facilities where the listed business and activities take place.
Background and normative framework analysis: An analysis of the mandatory anti-COVID national measures to be implemented in the aforementioned business and activities was undertaken. The two large public buildings were not included in this investigation due to the constant evolution of the legislative scenario for educational and health facilities.
Survey research through an online questionnaire: To define how users perceived the generally implemented anti-COVID measures in public and private buildings, an online survey research was carried out. The questionnaire did not refer to a specific building or business.
Case studies survey research: To define how users perceived the implemented anti-COVID measures in public and private buildings, an onsite survey research was carried out through a questionnaire in person. The questionnaire referred to the specific building or business users had just visited.
2.1. Observational Field Surveys
The observational field surveys were conducted in spring and summer 2021. These activities required the researchers to visit 76 facilities, taking annotations and pictures of the anti-COVID measures implemented at the entrance of each building, activity, or business, with prior consent of the supervisor.
Table 1 illustrates the different kinds of facilities considered.
Each identified measure was then classified according to its features and use.
2.2. Background and Normative Framework Analysis
The normative framework analysis at first involved a background investigation: the relationship between the different virus transmission modes and the several potential anti-COVID measures was examined to understand the reasons for their implementation and co-existence. Later, the legal reference framework for the business and activities was identified in the binding guidelines jointly developed by the Italian authorities (Summit of the Regions and Autonomous Provinces, Ministry for Health, and Technical-Scientific Committee). The two editions [
29,
30] issued in May 2020 and May 2021, respectively, fully covered the research timeframe.
2.3. Survey Research through an Online Questionnaire
The online survey, which took place between spring and autumn of 2021, required compiling a self-report questionnaire. The online questionnaire was specifically structured for the research to investigate the general users’ opinions and preferences about the anti-COVID measures adopted in activities open to the public, without a reference to a specific building or business. The questionnaire was realized through the Qualtrics software and remotely (online) administered. The participation was anonymous and voluntary; full information about the research was displayed before compiling, and consent to the use of personal data was requested. Overall, 203 questionnaires were collected and analyzed. The questionnaire was structured in four sections. The first section concerned social and demographic topics and information related to the individuals’ habits during the pandemic. The second section was conceived to explore the users’ preferences and opinions about the more commonly undertaken anti-COVID measures in buildings open to the public, focusing on hand-sanitizing devices, temperature-scanning instruments, and signage/wayfinding systems. In particular, to explore the users’ preferences related to different devices, multiple-choice questions combined with illustrative pictures were provided (e.g., different types of hand sanitizer dispensers). The third section explored four dimensions through 28 items in total, investigating the users’ perception of the three mentioned measures. The perceived hygiene dimension (4 items) assessed how much the presence of different devices fueled the perception of cleanliness. This factor is considered in the travel sector, where a significant change has been presented with the advent of the pandemic [
31,
32]. The perceived safety dimension (11 items) investigated the degree to which the person felt protected from the virus by the mitigation and prevention measures [
33]. The emotional impact dimension (8 items) investigated the user’s emotional reactions regarding the different types of devices [
34], such as whether or not the presence of the device impacted his/her fear of being infected. Finally, the social influence dimension (7 items) investigated the users’ perception of compliance with anti-COVID regulations in relation to the social context. In particular, it explored the individuals’ emotional reactions concerning the presence of other users within the structure. In fact, current literature reveals how the social context can influence people’s behaviors regarding the adoption of anti-COVID measures (e.g., washing hands [
35]). The participants’ answers were assessed through their agreement on a 5-point Likert scale (1 = I completely disagree; 2 = I partially disagree; 3 = I am neither in agreement nor in disagreement; 4 = I partially agree; 5 = I completely agree).
Table 2,
Table 3 and
Table 4 illustrate in detail the questionnaire items used in the third section. The fourth and final section investigated the users’ opinions about the most important elements from a safety perspective and the most worrying conditions in an indoor environment.
2.4. Case Studies Survey Research
The case study interviews were conducted between spring and autumn 2021 as well. Contrary to the online survey, the questionnaire was site-specific and concerned the anti-COVID measures implemented in the building the interviewee had just visited. Nine case studies were chosen, including different kinds of retail, a public office, catering, one university location, and one health facility, as detailed in
Table 5.
The data collection was agreed upon by the supervisor of each building, activity, or business, who granted his/her consent. The researchers conducted a site inspection in each facility to identify and classify the implemented measures at the entrance(s) and indoor. Then, they involved the users at the buildings’ exit(s) during opening hours for several weeks. Users were asked to fill out a self-report questionnaire accessed through a tablet (sanitized after each usage by the researcher) and a QR code. The instrument was specifically structured for the research to investigate the users’ opinions and preferences about the anti-COVID measures adopted in that specific building, activity, or business. The questionnaire was realized and administered through the Qualtrics software. The participation was anonymous and voluntary; full information about the research was displayed before compiling, and consent to the use of personal data was requested. The questionnaire was structured in five sections. The first section concerned social and demographic topics and information about the individuals’ habits during the pandemic and their personal experiences. The second section was conceived to explore the frequentation of the site and the perception of users about the presence/absence of the anti-COVID measures implemented in that building, activity, or business, with a specific focus on hand-sanitizing solutions, temperature-scanning instruments, signage/wayfinding system, and “green pass” (the Italian informal name used to identify a certificate providing proof of a complete course of vaccination against COVID-19) control. The third section focused on the users’ opinions, assessed through their agreement to several questions, expressed on a 5-point Likert scale (1 = I completely disagree; 2 = I partially disagree; 3 = I am neither in agreement nor in disagreement; 4 = I partially agree; 5 = I completely agree). The NA option (not applicable) was added in those cases where it was impossible to provide the degree of agreement (e.g., the investigated anti-COVID measure was not implemented in that case study). The items concerned the overall implementation of anti-COVID measures, the specifically used devices, and wayfinding, considering eight dimensions. The dimension of clarity of information and arrangement of the devices (3 items) investigated if the user considered the implemented measures clear and well-organized [
36]. The usability dimension (3 items) investigated if the individual found the functioning of the hand-sanitizing dispenser [
37] and the temperature measurement at the entrance [
38] simple and efficient. The perceived utility dimension (3 items) evaluated how much the individual found the anti-COVID measures adopted by the facility useful to limit the COVID-19 pandemic and to protect both their health and that of the community [
37,
39,
40]. The perceived safety dimension (3 items) investigated whether shared internal public spaces were perceived as safer in the presence of anti-COVID devices. Furthermore, it assessed the perception of other people’s compliance with anti-COVID measures [
33,
41]. The perception of hygiene and healthy spaces dimension (3 items) investigated the perception of people about the hygiene of the facility and the tidiness of the anti-COVID devices present in the structure [
32,
42,
43]. The social influence dimension (3 items) assessed the user’s emotional reactions concerning the social context and therefore to the other users and the staff within the structure [
44,
45]. The hand-sanitizer dispenser appreciation dimension (4 items) investigated the individual’s satisfaction concerning the dispenser’s material, shape, and aesthetics [
40]. Finally, the wayfinding dimension (4 items) explored the clarity and ease of understanding of vertical and horizontal routes-management signage. It also verified the ease of identifying entry and exit routes [
20,
43].
Table 6 and
Table 7 detail the investigated items and the related dimensions.
The fourth section concerned the opinions about the green pass and the related controls. The fifth section investigated the users’ opinion about the most important elements from a safety perspective and which were the most worrying conditions in an indoor environment. Overall, 528 questionnaires were collected; 429 of them were considered suitable for the analysis since the others were excluded, as the users proved incoherent answers, referred to devices and/or measures that were not implemented in the case study, or dropped out during the survey.
3. Results
3.1. Anti-COVID Measures Implemented
As was expected, hand-sanitizer dispensers (A) were the most widespread devices. The field surveys allowed defining three different sub-categories depending on the features, organization, and functioning of the dispensing system, as these characteristics can play a relevant role in influencing the users’ perception of these measures. Simple dispensers activated by pushing and not integrated into a specific structure or system (A1) represent the first of them. The second sub-category includes the hand-sanitizer dispensers activated by pushing but positioned in an ad hoc structure or system (A2). The third one consists of touchless hand sanitizers integrated into an ad hoc structure or system [A3].
A second quite common anti-COVID measure (B), mainly located in food retail facilities such as supermarkets or discounts, was the sanitizer dispensers for collectively used containers, such as baskets or carts.
In some cases, retail facilities (both food and non-food) also provided devices distributing disposable gloves (C). In personal service activities, devices distributing wrappers for personal effects (D), such as bags or backpacks, were sometimes available so that clients could ensure that no contaminated surface entered indoors. Nevertheless, compared to other anti-COVID measures, few facilities adopted these strategies.
On the contrary, wayfinding through vertical signage (E) was largely implemented. It was possible to distinguish two sub-categories according to the different messages the signage conveyed. The first one is represented by informative vertical signage (E1) providing general information about the maximum crowding allowed inside the facility or the necessity of wearing a mask before entering. The second sub-category includes vertical signage with spatial information (E2), such as social distancing instructions, circulation routes definition, or the identification of the entrance and exit.
Wayfinding through horizontal signage (F) was largely implemented as well. This category includes all the spatial information provided through graphic, tactile, and visual communication attached to the floor to help users choose a predetermined path.
Other identified devices pertaining to the wayfinding systems were route-demarcating elements (G), mainly chains or tapes physically obstructing predetermined pathways or separating the in/out circulation flows.
The temporary transparent barriers (H) were largely implemented, positioned in front of the desks and/or registers and separating employees from customers.
The last category of anti-COVID measures to be detected was the bodily temperature-measurement instruments, mainly infrared (IR) or digital thermoscanner (I), which were categorized in three sub-categories. The first one includes the portable mono-user IR thermoscanners (I1) activated by dedicated personnel. The second sub-category is represented by the fixed mono-user IR thermoscanner (I2), which is positioned on a dedicated vertical structure and/or on the wall. The third kind of detected thermoscanner was the digital and dynamic multi-user one (I3).
Figure 1 illustrates the incidence of each measure in the total number of examined facilities.
3.2. Background and Normative Framework Analysis
3.2.1. Modes of Transmission of the Virus and Anti-COVID Measures
As briefly illustrated in
Section 2, prior to the normative framework analysis, a background investigation dealt with the relationship between the three known modes of SARS-CoV-2 transmission and the most common anti-COVID measures implemented in the public and private buildings open to the public.
Figure 2 illustrates the emerging picture.
The background investigation allowed us to identify the following:
Properly sanitizing hands and surfaces allows to avoid contagion by fomites, while it does not hinder the airborne or droplet transmission of the virus;
Likewise, social distancing prevents the infection through a contact—meaning contact with mucous membranes of distinct individuals—and by droplet, while it does not prove itself useful in relation to the aerosol transmission mode;
Using personal protective equipment (PPE) such as face masks avoids both the airborne and droplet transmission of the virus, with the latter also prevented by physical barriers, but it does not hinder contagion by fomites.
This picture highlights how none of the examined measures, individually considered, allows for entirely avoiding the SARS-CoV-2 contagion.
Although not directly related to the known modes of transmission of the virus, temperature scanning represents another largely implemented measure. Since the beginning of the pandemic, individuals have been implored not to leave home in case of an alteration of body temperature, as it could be a symptom of infection. However, they do not always perform this self-monitoring, especially if they do not sense any change in their health. In this sense, body temperature scanning can be considered a prevention measure, as illustrated in
Figure 2. Therefore, hand and surface sanitizing, social distancing, and use of face masks—due to their individual inability to fully avoid the contagion—can be considered “mitigation” measures rather than prevention ones.
The background investigation represented a fundamental step prior to the normative framework analysis, as it allowed understanding both the reasons for the measures implemented and their necessary co-existence, especially because some of them were/are compulsory.
3.2.2. Normative Framework
As explained in the methods, the reference normative framework was identified in the binding guidelines developed in 2020 and 2021 by the Italian authorities and based on the WHO technical guidance [
46,
47]. Since this analysis followed the observational field survey, the examined business activities were the same ones involved in the previous investigation. The interpretation of the guidelines allowed defining, for each of the examined business/activities, both the compulsory and the suggested anti-COVID measures. Moreover, it was also possible to complete the picture emerging from these directives with the integrative mitigation/prevention measures identified through the field survey and spontaneously implemented although neither compulsory nor suggested.
Table 9 summarizes the results of the normative analysis completed by the ones deriving from the observational field survey.
The results show the following:
The only mandatory anti-COVID measures to be implemented in each of the examined categories were the provision of hand-sanitizer dispensers (A) and the display of informative vertical signage (E1);
Horizontal signage (F) was a mandatory measure to be implemented only for open-air retail and was not even suggested for the other activities. However, as the observational field survey proves, it was adopted—with different degrees—in each of the categories;
Vertical signage with spatial information (E2) and route-demarcating elements (G), although never mentioned in the guidelines, were largely adopted in the retail context, as the observational field analysis proved;
The temporary transparent barriers (H), which, according to the observational field survey, were largely installed, were in fact suggested in many of the cases and mandatory for offices;
The temperature measurement was a suggested measure for any indoor activity as a prevention measure.
Besides the guidelines strictly related to the categorized indoor mitigation/prevention measures, three additional relevant topics emerge from the normative analysis:
The importance of PPE (more specifically, of wearing protective masks);
The need to avoid crowding also through ensuring a proper management of the users’ flows in relation to the specific indoor environment features;
Increasing natural ventilation as well as, in case of mechanical ventilation, increasing air-change rates and excluding recirculation in HVAC are strongly recommended.
3.3. Survey Research through an Online Questionnaire: Users’ Perception of the Generally Implemented Anti-COVID Measures
Overall, 203 participants took part in the investigation (127 females). The average age was 40.58 years (minimum age 18 years–maximum age 78 years; SD = 15.30. In particular, 50% of users (n = 101) were aged between 18 and 35 and 45% (n = 92) between 36 and 65, while the remaining 5% (n = 10) were over 65. Regarding previous experiences with the virus, 158 participants reported direct or indirect experiences with COVID-19; of these, 28 said they were directly infected. The remaining 45 participants said they had no experience of direct or indirect interaction with the virus.
The survey research through the online questionnaire allowed achieving two kinds of results for each of the three investigated prevention measures—hand-sanitizing systems (
Section 3.3.1), temperature-measurement instruments (
Section 3.3.2), and wayfinding/signage (
Section 3.3.3). On the one hand, it was possible to identify the users’ preferences concerning each device or system’s kind and operation. On the other, statistical analysis performed investigates the different evaluation scores given by the participants to the dimensions and items of the questionnaire—hygiene perception, safety perception, emotional impact, and social influence. In particular, a series of one-sample Wilcoxon tests was run, comparing the scores that participants assigned to each dimension with the median value of the scale (
Mdn = 3) with BH-adjusted
p-values [
48]. In addition, the fourth section of the questionnaire allowed achieving a third result: identifying the most important elements and the most worrying conditions in indoor environments according to the users (
Section 3.3.4).
3.3.1. Hand-Sanitizing Systems
Among 203 participants, 167 preferred the touchless hand-sanitizer dispensers with a support (A3), 27 had no preferences, 8 indicated the hand-sanitizer dispenser activated by pushing (A1, A2) (with or without an ad hoc structure or system), and 1 user reported “other” options, as illustrated in
Figure 3.
As illustrated in
Figure 4, all the investigated dimensions achieved positive results, in particular the dimensions and items of emotional impact (
V = 14,754,
p < 0.001;
Mdn = 4.00,
M = 4.02,
SD = 0.88) and social influence (
V = 16,086,
p < 0.001;
Mdn = 4.00,
M = 3.94,
SD = 0.97). In fact, the presence of hand sanitizer does not increase the participants’ fear of being infected (
V = 17,518,
p < 0.001;
Mdn = 5.00,
M = 4.54,
SD = 1.11) and increases their degree of attention in relation to the contagion (
V = 8864,
p < 0.001;
Mdn = 4.00,
M = 3.50,
SD = 1.30). The perceived safety also appears statistically significant (
V = 17,792,
p < 0.001;
Mdn = 4.25,
M = 4.10,
SD = 0.88) since users find the presence of hand sanitizers useful for their safety both at the entrances (
V = 15,827,
p < 0.001;
Mdn = 5.00,
M = 4.20,
SD = 1.08) and exits of the building (
V = 14,838,
p < 0.001;
Mdn = 4.00,
M = 4.09, S
D = 1.17) and indoors (
V = 13,352,
p < 0.001;
Mdn = 4.00,
M = 3.89,
SD = 1.21).
Table A1 provides the detailed data.
3.3.2. Temperature-Measurement Instruments
Among 203 participants, 71 preferred the fixed mono-user IR thermoscanners (I2), 57 had no preferences, and 43 preferred the portable mono-user IR thermoscanners (I1). Thirty-one users reported they would rather integrate the thermoscanner into the hand-sanitizing system, and one user reported “other” options.
Figure 5 illustrates the results.
Concerning the users’ perception, the questionnaire results displayed in
Figure 6 indicate how the use of a temperature-measurement device at the entrance of a building is considered useful from a safety perspective (
V = 13,274,
p < 0.001;
Mdn = 4.00,
M = 3.93,
SD = 1.18). Moreover, it increases the degree of attention in relation to the contagion without increasing the fear of being infected (
V = 7320.5,
p = 0.01;
Mdn = 3.00,
M = 3.28,
SD = 1.34) and has a positive emotional impact (
V = 11,522,
p < 0.001;
Mdn = 4.00,
M = 3.79,
SD = 0.89). The social influence dimension achieved good scores as well since the use of a thermoscanner is not perceived as embarrassing (
V = 16,290,
p < 0.001;
Mdn = 5.00,
M = 4.47,
SD = 1.12.).
Table A2 provides the detailed data.
3.3.3. Signage and Wayfinding Systems
As illustrated in
Figure 7, more than 50% of the participants (109 on 203) revealed preference for a combination of vertical (E1, E2) and horizontal (F) signage. Moreover, the use of vertical signage only (
n = 9) was less preferred than the use of the horizontal one only (
n = 53), while twenty-six participants expressed no preferences, and two users reported “other” options.
With regard to the wayfinding system perception, illustrated in
Figure 8, the signage marking both the users’ routes and the social distancing are considered useful from a safety perspective (
V = 17,584,
p < 0.001;
Mdn = 4.00,
M = 3.83,
SD = 0.74). The emotional impact has high scores (
V = 15,598,
p < 0.001;
Mdn = 4.00,
M = 3.82,
SD = 0.86) since wayfinding systems increase the degree of attention in relation to the contagion (
V = 11,816,
p < 0.001;
Mdn = 4.00,
M = 3.63,
SD = 1.43) without increasing the fear of being infected (
V = 14,266,
p < 0.001;
Mdn = 5.00,
M = 4.37,
SD = 1.05). As for the social influence, following predetermined routes is not considered annoying (
V = 10,812,
p < 0.001;
Mdn = 4.00,
M = 3.67,
SD = 1.43), while it bothers the users if other individuals do not follow the signage instructions (
V = 11,771,
p < 0.001;
Mdn = 4.00,
M = 3.84,
SD = 1.31).
Table A3 provides the detailed data.
3.3.4. Safety: Important Elements and Most Worrying Conditions
The fourth and final section of the online questionnaire investigated the users’ opinions about the most important elements from a safety perspective and the most worrying conditions in an indoor environment. For each of the two questions, the participant could report up to two options. This investigation is meant to contextualize the results related to hand sanitizer, thermoscanner, and wayfinding, relating them to other features of indoor environments that are relevant for the SARS-CoV-2 transmission. As
Figure 9 highlights, users acknowledged how the airborne and droplet modes of transmission represent the biggest hazards. In fact, the (natural or mechanical) air-change rates are considered the most considerable factor from a safety perspective (40%), and signage informing about the maximum indoor crowding allowed was mentioned in 16% of answers. Likewise, the most worrying conditions comprised indoor overcrowding (42,5%), lack of air change (29%), and gatherings (21%), as
Figure 10 shows.
3.4. Case Studies Survey Research: Users’ Perception of the Site-Specific Anti-COVID Measures
Table 10 details the anti-COVID systems and devices adopted in the different buildings, activities, or businesses mentioned in
Table 5.
If compared to the others, the hospital is, as expected, the building implementing the largest number of mitigation/prevention measures, together with the university location and the public office. The supermarket, the shopping center, and the clothes shop also adopted a several anti-COVID measures, while the catering activities only implemented the compulsory ones (A, E1).
This survey allowed comparing the results concerning the general implementation of the anti-COVID measures and the used devices of all case studies in relation to eight different dimensions: clarity of information and arrangement of the devices, usability, perceived usefulness, perceived safety, perceived hygiene and health, social influence, hand sanitizer dispenser appreciation (
Section 3.4.1). A specific comparison addressed the wayfinding dimension (
Section 3.4.2). In particular, a series of Kruskal–Wallis tests was run; thereafter, a series of post hoc Mann–Whitney tests with BH correction was conducted when the previous tests showed statistically significant results. In addition, the last section of the questionnaire allowed identifying the most important elements and the most worrying conditions in indoor environments according to the users (
Section 3.4.3).
Appendix B provides the tables reporting the descriptive analyses (
M,
SD,
Mdn) and the statistics analyses concerning the perception of the participants by comparing the different case studies (
Appendix B.2,
Table A6,
Table A7,
Table A8,
Table A9,
Table A10,
Table A11,
Table A12,
Table A13,
Table A14,
Table A15,
Table A16,
Table A17,
Table A18,
Table A19,
Table A20,
Table A21,
Table A22,
Table A23,
Table A24,
Table A25,
Table A26,
Table A27 and
Table A28).
3.4.1. Post-Experience Questionnaire Results on General Implementation and Devices
Overall, the final sample consisted of 429 participants (127 female). The detailed descriptive data of the sample for each single case study are reported in
Appendix B (
Appendix B.2,
Table A4 and
Table A5).
Table 11 shows the results of each case study. In particular, it reports the median values scored for the items related to the implementation of the mitigation/prevention measures and the used devices, illustrated in
Table 6 (
Section 2.4).
Concerning the clarity of information and the arrangement of the devices (items 1–3), the participants expressed a generally positive opinion for each case study. In more detail:
CS5 (public office) and CS7 (restaurant) achieved the best scores; moreover, CS5 also implemented wayfinding and temperature measurement;
CS8 (pub—night) and CS9 (bar—evening) scored the worst results for the organization of the measures in the entrance area. This can be linked to the fact that, in the first case, there was no signage or infographic related to the use of the hand sanitizer, a dispenser activated by pushing (A), while, in the second case, the position of the hand-sanitizing system was scarcely within sight (behind the entrance door);
In CS1 (supermarket) and CS2 (superstore), users found it difficult to locate the hand-sanitizing systems installed in the indoor environment.
With regard to the usability dimension (items 4–6):
The hand-sanitizing system that users considered the most intuitive was the one in CS7 (restaurant), a touchless device with an ad hoc structure (A3) and vertical signage [E1] encouraging users to sanitize their hands through an infographic representing the sanitizing procedure;
CS4 (university location), CS5 (public office), and CS9 (bar—evening) had well-received high scores in relation to the respective intuitiveness of the hand-sanitizing systems, all of which were touchless devices with an ad hoc structure (A3) (CS5, CS9) or secured to the wall (CS4);
No significant differences concerning the thermoscanner usability emerged, and people found no difficulties in measuring their temperature; this measure was present only in CS3 and CS5, and in both cases it was a fixed mono-user thermoscanner [I2].
About the perceived usefulness (items 7–9) of the anti-COVID measures:
In no case study did the participants express that the implemented measures were a waste of time; the least performant building was CS4 (university location), where dedicated personnel checked the access;
The participants largely acknowledged the usefulness of sanitizing their hands in each structure.
Concerning the perceived safety (items 10–12):
Users felt safe in each of the indoor environments; in particular, CS5 (public office) and CS7 (restaurant) scored the highest marks, while CS8 (bar—night) and CS9 (bar—evening) scored less-positive results alongside CS2 (superstore). This could be explained by the fact that users can access CS5 only by appointment and CS7 only by the instructions of the staff at the entrance; hence, in these facilities, a regulation of the flows is performed, while CS8, CS9, and CS2 are generally well-frequented businesses without such controls at the entrance. This perspective is confirmed by the fact that CS5 is also perceived as the less-crowded facility;
None of the buildings was considered too crowded although CS3 (hospital) and CS4 (university location) achieved the lowest scores despite from the considerable size of their indoor environments, which could potentially be reassuring instead;
The participants found that other users generally respected the anti-COVID measures although CS1 (supermarket), CS2 (superstore), CS9 (bar-evening), and in particular CS3 (hospital) appeared the least performant case studies.
With regard to the perceived hygiene and health (items 13–14):
All the facilities were considered careful in hygiene terms; in particular, CS5 (public office) and CS7 (restaurant) scored the highest marks—an opinion that can be linked to the perceived safety results;
The hand-sanitizer dispenser systems considered the most hygienic were the ones in CS5 (public office), CS7 (restaurant), and CS9 (bar—evening)—touchless ones with an ad hoc structure (A3)—while the one in CS2 (superstore), a simple hand-sanitizer dispenser activated by pushing (A1), scored the worst results.
The results concerning the social influence dimension (items 16–17) show how:
The participants were not worried by crowding in the indoor environments apart for the CS1 (supermarket), CS3 (hospital), and CS8 (pub—night) cases: this could be linked to the fact that CS1 and CS8 are usually well-frequented businesses without access control, while a healthcare facility is perceived as an environment to be shared with potentially infected individuals;
No anxiety was derived from other users not following the mitigation/prevention measures although CS3 (hospital) and CS7 (restaurant) scored lower results than the other case studies.
With regard to the hand-sanitizer dispenser section (items 19–22), the main results are:
The less-appreciated dispenser materials were the ones used in CS8 (pub—night) and CS4 (university location), which were both transparent plastic containers activated by pushing (A1);
The most appreciated shapes for the hand-sanitizing systems were the ones in CS6 (clothing shop), CS7 (restaurant), CS5 (public office), and CS9 (bar—evening), all of them distinguished by matte surfaces and an ad hoc structure (A3);
Users acknowledged a proper stability of the system hand-sanitizing system in each case study although CS1 (supermarket), CS4 (university location), and CS8 (pub—night), in which a dispenser activated by pushing (A1) was used, reached lower scores;
The hand-sanitizing system was definitely considered aesthetically not pleasing in CS1 (supermarket) and CS8 (pub—night), where transparent and activated-by-pushing dispensers (A1) were used, while CS7 (restaurant) was the facility achieving the highest score.
3.4.2. Post-Experience Questionnaire Results on Wayfinding Systems
Table 12 details the results, expressed on a Likert scale from 1 to 5, that each case study scored for the items pertaining to the wayfinding dimension, illustrated in
Table 7 (
Section 2.4).
Concerning the wayfinding (items 23–26), case studies 7, 8, and 9 could not be compared since, in these facilities, only the (mandatory) vertical signage was implemented. The results of the onsite questionnaire highlight how:
Besides the CS2 (superstore) case, the signage for anti-COVID circulation routes was always considered clear, and the most effective results were achieved in CS5 (public office) and CS3 (hospital), which used a combination of vertical and horizontal signage;
Identifying the entrance and exit paths was considered easy in all the case studies; CS3 (hospital) and CS5 (public office) had the highest score, while CS2 (superstore) and CS4 (university location) are the two facilities with the lower ones: this can be linked to the fact that CS2 and CS4 did not present specific signage identifying the entrance(s) and exit(s);
Users generally found the horizontal signage very clear, and only CS2 (superstore) achieved a lower result—a business in which the signage marked the interpersonal distance near the desks but not the preferred internal routes for circulation;
CS3 (hospital) was the case study with higher scores in terms of easy understanding of the vertical signage and the routes demarcating devices, while CS1 (supermarket) achieved a score clearly below the others.
3.4.3. Safety: Important Elements and Most Worrying Conditions
As in the online survey, the case studies questionnaire also investigated which were the most important elements in preventing SARS-CoV-2 transmission and which were the most worrying ones in the indoor environment they had just visited. As
Figure 11 highlights, users confirmed the importance of air-change rates from a safety perspective (58%)—an opinion also supported by the regulation of entrances (22%), followed by the hand-sanitizing systems (56%), and the temperature measurements (18%). Likewise, overcrowding (56%), lack of air change (46%), and gatherings (34%) represent the most worrying conditions, as
Figure 12 shows.
5. Conclusions
The SARS-CoV-2 pandemic abruptly overturned the usual fruition of indoor spaces, and adaptive measures were suddenly required to limit the virus from spreading inside buildings, guiding the users’ actions and encouraging their proper behaviors. These premises highlight the importance of investigating how the individuals perceive these physical devices through their feedback as a fundamental means to improve the overall effectiveness of anti-COVID indoor strategies.
By identifying the most appropriate design features of the undertaken measures, the presented research contributes to building a knowledge framework supporting novel design strategies to be implemented in buildings. The results show how individuals generally acknowledge the usefulness of the mitigation/prevention measures most commonly carried out in buildings, proving their effectiveness in promoting users’ safety perception. Moreover, hand sanitizers, temperature-measurement instruments, and wayfinding systems encourage the users’ proper behavior without producing embarrassment. Finally, the regulation of flows proves to be an important strategy to increase the individuals’ safety perception in relation to overcrowding.
The research also identifies specific design characteristics for the design of anti-COVID systems that could encourage people’s awareness and proper behaviors in indoor environments.
However, the research shows some limitations partly due to the health emergency restrictions on people’s circulation and activities. While investigating case studies in different scenarios allowed a broader overview related to indoor environments open to the public, analyzing the same set of buildings in each method would have increased consistency. The geographic perimeter of the investigation is restricted to a regional one although it can be considered representative of the Italian one due to the national nature of the anti-COVID regulation. The normative framework changed during the research timeframe, leading to the later introduction of the “green pass”, a topic that was therefore taken into account only in the case studies survey research and not addressed in this paper.
The results presented in the paper are the first outputs of an interdisciplinary research focusing on the relationship between users’ perceptions and the design of anti-COVID measures in indoor environments. The identified design aspects are a preliminary contribution to the development and implementation of effective anti-COVID systems that are satisfactory to users in public spaces.